In 1964, Lengiprotransmost developed a project for a floating crane PRK-100 with a lifting capacity of 100 T intended for installation and loading and unloading operations on the construction of bridges and on construction sites near water bodies.
The crane is collapsible, the maximum weight of an individual element does not exceed 7 T. The crane can be transported to the construction site either by railway, and by road transport, since all elements of the crane easily fit into railway and road dimensions.
The crane is mounted on a dinghy of 24 KS-type pontoons, prepared in advance at the construction site. Assembling the upper structure of the crane on a ready-made pontoon takes 12 - 15 days if there are 10 assembly cranes (mobile or floating). The dismantling of the crane is completed in 10 - 12 days.
The PRK-100 crane is equipped with two hooks: the main hook with a lifting capacity of 100 tons and an auxiliary hook with a lifting capacity of 30 T. With a load on the hook up to 30 T
upper part The tap can be rotated 90° in both directions. The turn is carried out using a winch installed on the pontoon. With a load weighing more than 30 T the crane rotates together with the pontoon. In this case, jamming devices are installed under the boom support hinges and in the rear part of the turntable. The crane's maneuvers on the water are ensured by four papillonage winches equipped with rope handlers, as well as all the equipment necessary for papillonage work.
All crane winches, including 3 cargo and 1 jib, are powered by its own AD-75T/400 power plant with a capacity of 75 kW, installed on the crane's scaffold. The control of electric drives is concentrated in the crane operator's cabin.
The PRK-100 crane differs from existing universal floating full-rotating cranes in its low weight, prefabricability, and shallow draft. The cost of its production is 6 times less than that of universal cranes; it is serviced by 4 people instead of 10.
A prototype of the PRK-100 crane, manufactured by the Uglich Mechanical Repair Plant, has passed all tests and is operated by Mostootryad No. 11 in Leningrad on the river. Neva has been having it for 1.5 years now. The acceptance commission of the USSR Ministry of Transport recommended it for mass production.
| Structural diagram of the PRK-100 crane |
Technical characteristics of the PRK-100 crane
| Maximum load capacity, ts: | |
| on the main hook | 100 |
| on auxiliary hook | 30 |
| Useful boom reach (from the side of the pontoon), m: | |
| with load 100 T: smallest | 3 |
| . with load 100 T: largest | 10 |
| . with load 30 T: smallest | 5 |
| . with load 30 T: largest | 22 |
| The height of the hook lifting from the surface of the water, with a departure of 10 m, m | 30 |
| Load lifting speed (on main / auxiliary hook), m/min | 1,7 / 3 |
| Crane slewing speed with load 30 T on a hook rpm | 0,11 |
| The speed of movement of the crane using papillon winches, rpm | 5 |
| Draft (during crane operation), m | 1,6 |
| Weight of the superstructure (without dinghy), T | 215 |
GANZ– one of the oldest brands of floating cranes in the world, is represented by a complete model range, which, according to the purpose of floating cranes, can be classified as:
Cargo grab floating cranes
Load capacity from 5 to 60 tons. Fully rotating, with a straight or articulated boom with a rigid guy. Towed or self-propelled. Fully autonomous or shift-shift design. For handling large volumes of all types of bulk/bulk cargo. Due to the combination of increased buoyancy, stability and yaw of the floating crane design as a whole with high speed of all main operations, it is achieved high performance overload: from 300 to 2000 tons/hour. They can have river, sea, and ice class. In floating cranes over 5 tons, a 4-rope grab is used. Used as a dredger for deepening the bottom with the possibility of equipping it with a belt conveyor for unloading the extracted soil. The ability to work in hook mode, which increases the load capacity, but reduces the speed of operations.
Cargo hook floating cranes
Load capacity from 5 to 200 tons. Fully rotating, with a straight or articulated boom with a rigid guy. Towed or self-propelled. Fully autonomous or shift-shift design. For handling piece and heavy loads. With other similar characteristics, what distinguishes them from cargo grab floating cranes is the presence of reduced speeds for performing basic operations required for more precise work. They can have river, sea, and ice class.
Installation and construction floating cranes
Load capacity from 16 to 300 tons. Fully rotating, with a straight or articulated boom with a rigid guy. Towed or self-propelled. Fully autonomous or shift-shift design. They are used in shipbuilding, heavy, energy, transport engineering, construction of bridges and hydraulic structures, as well as work on the development of the sea shelf. It operates at reduced speeds: 1-12 meters/minute. They can be of river, sea, or ice class.
Installation and rescue floating cranes
Loading capacity from 200 to 500 tons and above. With straight, inclined fixed boom system. Towed or self-propelled. Fully autonomous or shift-shift design. In accordance with the purpose, they can be equipped with a variety of auxiliary equipment. They are used in shipbuilding, heavy, energy, transport engineering, construction of bridges and hydraulic structures, work on the development of the sea shelf and underwater rescue work. Speed mode: 0.1-5 meters/minute. They can be of river, sea, or ice class. It is possible to equip the boom with a trunk for working with loads less than the rated load capacity in cases where a very large boom reach is required.
Floating crane– extremely versatile and reliable equipment. They are used for loading and unloading ships, dredging work, building bridges and other water structures.
Floating crane practically indispensable in the port for multi-purpose work, thanks to which the relatively high cost pays off in a short time.
- Floating crane with lifting capacity 16 t
- Floating crane with lifting capacity 32 t (Al Furat)
- Floating crane with lifting capacity 32 t (Hafez)
- Floating crane with a lifting capacity of 100 t (El Mansour)
Design features and characteristics of floating cranes
1. Taps for river construction
For the construction of ports and bridges on inland waterways, universal floating cranes with a lifting capacity of 10 to 60 tons, collapsible cranes with a lifting capacity of 30-100 tons, pile driver cranes with a lifting capacity of 25-30 tons, and combined land cranes installed on floating craft are used.
Universal taps
The Kirovets crane type KPL G/K 10-30 with a lifting capacity of 10 tons at all boom radii was produced by the plant named after. Kirov in Leningrad in grab and hook versions.
The crane is full-rotating, the boom of a lattice structure with a jib is pivotally connected to a movable counterweight for balancing. When the reach changes, the jib moves in the opposite direction to the boom (it lowers when the boom rises), so that when the reach changes, the load remains at the same height.
The rotating part of the crane with the boom mounted on it and all the lifting and turning mechanisms is located on rollers moving along the lower rim located on a beam cage 2.1 meters high from the deck.
Crane motors AC voltage 220-380 V, total power 267 kW. Electric power is supplied from a diesel generator set located in the pontoon body or on the shore. The crane control is electromechanical.
The crane is non-self-propelled and moves using mooring lines and winches.
To bring the crane into the transport position, the boom is lowered; after dismantling the mechanism for changing the boom radius, the height of the crane is reduced to 10 m.
The crane is designed for loading and unloading operations and therefore has high speeds for all operations. For installation work The crane is not recommended due to insufficient lifting capacity, but can be used as an auxiliary crane at a concrete plant for supplying aggregates and cement from water, for unloading timber and other cargo. With the light weight of the mounted elements, the crane can also be used for construction work.
Rice. 1. Diagram of a universal floating crane type KPL G/K 10-30: 1-yoke and boom counterweight; 2-rod for changing the boom radius; 3- engine room with control cabin; 4 - rotary mechanism
The crane from Valmet (Finland), built in 1958, with a lifting capacity of 10 tons (Fig. 2), is fully revolving, equipped with a hook and a grab.
The crane's lattice boom is 28 m long with a rack and pinion device for changing the reach. Cranes from this company are also produced with a boom that has a jib at the end.
The rotating platform of the crane with lifting mechanisms, a control cabin and a boom located on it is installed on balancing trolleys moving along a rail rim laid on a beam pedestal on the pontoon deck. The moving part of the crane is attached to a fixed base using a hollow axial journal with bearings.
Electric crane motors AC (380 V), independent for each movement. The crane control is electromechanical. The power plant consists of two diesel engines with a capacity of 180 hp each. With. with alternating current generators of 150 kVA.
The crane's pontoon contains living quarters, and on the deck there is a dining room, galley, shower room, storage room and other auxiliary rooms. The crane team consists of 11 people. during two-shift work. The crane is not self-propelled and during operation it moves on mooring ends.
Lowering the crane boom onto the pontoon for the transport position is not provided, so its height from the water in an undisassembled state is 25 m, which is why the crane cannot pass under bridges. When dismantling the boom, the height of the crane is reduced to 16 m, and when dismantling the lever device of the boom counterweight - to 12 m. In this position, the crane becomes transportable along inland waterways.
Rice. 2. Diagram of a universal floating crane from the Valmet company: 1 - lever device with a jib counterweight; 2-rack mechanism for changing the boom reach; 3- control cabin; 4 – diesel generator set; 5 – engine room
The crane is intended mainly for loading and unloading operations. In the construction of port and bridge structures, the crane can be used as an auxiliary crane for transshipment of bulk cargo and for the construction of berths from wooden and metal sheet piles and light types of reinforced concrete sheet piles and piles.
The Kpl 15-30 type crane (Fig. 3) is produced by the Teplokhod plant (USSR).
The crane is full-rotating with one hook with a lifting capacity of 15 tons at all reach. The hook can be replaced with a grab. The crane boom is pivotally connected to a movable counterweight, which makes it much easier to change the reach.
The rotating part of the crane with all the lifting mechanisms and the boom rests on rollers rolling along the vent mounted on a beam cage on top of the pontoon deck.
Crane motors three-phase current 220/380 V are driven by a diesel generator set with a capacity of 375 kVA, located in the hull of the vessel (diesel type 84-23/30, generator MS 375-750). The crane control is pneumatic. The team consists of 10 people. during two-shift work.
Rice. 3. Diagram of a universal floating crane type KPL 15-30: 1 - control cabin; 2 - lever device with hydraulic drive for changing the boom radius; 3 - boom counterweight; 4 - machine room; 5 - rack for placing the boom in transport position
The crane is not self-propelled and moves during operation using electric pins, and is towed over long distances. In the transport position, the boom is laid along the pontoon on a stand.
The crane is designed for river navigation conditions and is intended for processing bulk and bulk cargo. However, according to its characteristics, it can be successfully used for the construction of river berths from prismatic and T-shaped reinforced concrete sheet piles. Thanks to its long reach, it can drive anchor piles, install anchor plates and install anchor rods. The high height of the hook allows it to load piles up to 20 m long. The crane can be used in conjunction with a crane with a large lifting capacity (50-100 tons), but with a smaller reach and lifting height (for example, for installing a vibrator for hollowing out reinforced concrete shells).
concrete walls with an angle profile when constructing them “into the water”. For the installation of sea piers and bridge works, the crane can only be used as an auxiliary crane if a crane with a higher lifting capacity is available.
Valmet cranes and type Kpl G/K 10-30 are available in small quantities and therefore their use is limited to home ports. Cranes "Bleichert" and type Kpl 15-30 have found wider application and are recommended for river hydraulic work.
In addition to the cranes described, a number of universal floating cranes with a lifting capacity of 30-60 tons, intended mainly for offshore construction and discussed below, are used in river hydraulic engineering.
Collapsible cranes
The crane type PRK-30/40, made according to the Lengiprotransmost project, is non-rotating, assembled on a dinghy of 12 pontoons. The crane's lifting capacity with a normal boom length of 32.5 m and an outreach of 2 m from the end (transom) of the saddle is 40 t, with zero outreach - 45 t. When installing a shortened boom 26.3 m long, the load capacity at zero outreach increases to 47.5 t . Loading capacity of the auxiliary hook is 10 tons at all ranges.
All crane structures are welded; the largest weight of the element is 4 tons. The crane boom consists of two branches at the bottom, which are then combined into one. The crane boom is connected by guy ropes to a swinging A-shaped tubular strut 3. The reach is changed using a pulley at a speed of 0.85 m/min. A pile driver guide with a telescopic spacer can be attached to the top of the boom for driving piles weighing up to 12 tons with an 8-hammer. Piles can be driven both vertical and inclined with a slope of 4: 1 on both sides of the vertical, i.e. under the pontoon and from the pontoon. The crane is mounted on a frame consisting of I-beams and channels with bolted joints, laid on top of the pontoons and fastened to them.
The crane mechanisms consist of drive jib and cargo winches type 1 UL-5 with a lifting capacity of 5 tons and a power plant type ZhES-60. Control of all mechanisms is concentrated in the cockpit. The crane is equipped with automatic limit switches for the load and boom. For anchoring and mooring operations, four UL-3 type drive winches with a lifting capacity of 3 tons, manual rollers for lifting anchors at the corners of the pontoon, bollards and bale strips are installed. The pontoon is surrounded by a fender and railing. To differentiate the crane, 40 tons of water (ballast) are poured into the aft pontoons. The crane is moved by two motor pontoons that are part of the pontoon. The permanent crane team consists of 5 people. per shift.
Rice. 4. Scheme of a floating crane type PRK-30/40: 1 boom; 2 boom guy; 3- swinging strut; 4 - jib pulley; 5 - jib winch; 6 - power plant ZhES-60; 7 - cargo winches; 8 - beam cage (frame) of the crane; 9- anchor catwalks; 10 - water ballast; 11- telescopic spacer of the pile driver boom; 12 - suspended pile driver boom; 13 - mooring winches; 14 - control cabin
The crane is designed for river conditions with navigation area “R” (large rivers). The freeboard height during operation is 0.19 m.
The height of the crane with the boom lowered is about 14 m, and with the boom strut lowered it is about 6 m.
Installation and dismantling of the crane is carried out using truck cranes of types K-52 and K-104. To transport the crane, 12 MAZ-200 and four ZIL-150 vehicles are required.
The PRK-30/40 crane is easy to manufacture and assemble and is intended mainly for the construction of temporary bridges (including the installation of spans). It can also be used in the construction of supports for permanent bridges and river hydraulic structures.
The main disadvantages of the crane are the lack of boom rotation and low speeds of lifting the load and boom, which sharply reduces its productivity compared to universal full-rotating floating cranes.
The crane type PRK-100 is manufactured by the factories of the Ministry of Transport Construction according to the Lengiprotransmost project. The crane is assembled on a pontoon of 24 KS-3 type pontoons (main assembly). The lifting capacity on the main hook is 100 tons. With this lifting capacity, the crane operates as a fixed crane. On an auxiliary hook with a lifting capacity of 30 tons, the crane operates with a rotation of 90° in both directions from the longitudinal axis. The crane can also be assembled on 16 pontoons (lightweight assembly); at the same time, it operates as a fixed-rotating one with a maximum lifting capacity of 70 tons.
The crane boom is a two-leg welded boom, consisting of four elements 8-11.5 m long, assembled with bolts. The boom is mounted on the hinge of the turntable and is held by a link guy, which transmits force to the strut 9 and the stretched stand with a counterweight. Changing the reach is carried out using a jib pulley.
The upper rotating frame consists of I-beams connected with bolts. All cargo, boom and rotary winches, a power station and a control panel are installed on the frame. The rotating frame moves on four balancing trolleys of two rollers each along a rail ring with a diameter of 12 m, mounted on a distribution frame. The rotating part is fixed to the lower distribution frame by a central axle with bearings.
The crane is equipped with load and roll limiters and limit switches for load, boom and slew. Wedging devices are installed on the distribution frame, ensuring that the rotation is turned off when the crane is operating with a load of over 30 tons and during “easy assembly”. The crane mechanisms consist of UL-8A traction winches for the main and auxiliary hooks. The turn is carried out by a winch with a traction force of 20 tons. The diesel generator set is represented by diesel engine 1-D-150AD with a capacity of 150 hp. With. and a PS-93-4 generator with a power of 75 kW of alternating current and a voltage of 230 V.
The cycles of auxiliary lifting and swinging or boom lifting, boom lifting and swinging, mooring operations and swinging or lifting the boom or auxiliary lifting can be combined simultaneously.
Rice. 5. Diagram of a floating crane type PRK-100 (main assembly): 1- boom; 2-link boom guy; 3-boom chain hoist; 4 - stand; 5 - counterweight; 6 – anchor windlass; 7 - distribution frame; 8 – upper rotating frame; 9 - strut; 10 – control panel; 11 - power plant; 12 – 15 - cargo, rotary, boom and mooring winches, respectively; 16 - ballast pontoons
Four mooring winches of the UL-5 type with a traction force of 5 tons and a cable speed of 5 m/min are installed on the dinghy. The dinghy at the corners is equipped with guide devices in the form of rollers and bollards, rollers for raising anchors, two Hall anchors weighing 400 and 300 kg, lifted by a windlass, a fender beam and a railing. Two pontoons of the pontoon 16 are filled with water to differentiate the crane. There are no residential or domestic premises on the crane.
When moving with a load, the crane is towed by a vessel with a capacity of at least 600 hp. With. The crane can operate in waves of no more than 1 point, since the deck rises above the water by only 0.3 m. Considering that the height of the crane, even with the boom lowered horizontally, is 16 m, it must be partially or completely disassembled during transportation.
The cranePRK-100 is designed for immersing shells, installing prefabricated supports and hanging installation of reinforced concrete spans, as well as for the construction of river port structures. The disadvantages of the crane are a reduction in lifting capacity to 30 tons when turning and low speeds of all movements (twice slower than universal floating cranes). Installation of reinforced concrete structures weighing over 30 tons, which requires high precision of aiming, in the absence of rotation, must be carried out with mooring winches, which is very difficult. Therefore, the use of this crane should be considered as temporary until the creation of universal floating cranes with a lifting capacity of 50 - 100 tons for river conditions.
2. Cranes for offshore construction
For the construction of jetties, berths and strengthening of sea shores in the USSR, mainly universal floating cranes with a lifting capacity of 30 to 100 tons are used. In some cases (for example, when constructing foundations for oil rigs in the Caspian Sea), a 250-ton floating crane is used. Abroad, in the construction of massive piers, floating cranes with a lifting capacity of 200-400 tons are used.
Rice. 6. Lifting capacity curves of the PRK-Yu0 crane: 1 - main hook; 2- auxiliary hook; 3-main hook for easy assembly
Universal cranes with lifting capacity 30-60 t
Crane from Tournay (USA), manufactured in 1940-1945. full-rotating with two hooks 30 and 8 t (Fig. 7). The small hook can be replaced with a grab. Lattice boom; Changing the boom's reach is done using a pulley. The engine room with cargo winches, boom, engine and control cabin rotates on rollers along a ring mounted on a beam cage on top of the pontoon deck.
Rice. 7. Scheme of a floating 30-m. crane "Tourney": 1 - machine and diesel rooms; 2- jib for fastening the stationary block of the boom pulley; 3 - control cabin; 4 - rotary roller device; 5 - stand for placing the boom in the stowed position
The crane is non-self-propelled and its movement during operation is carried out at the mooring ends using electric pins. The power of the main diesel engine of the installation is 150 hp. e., auxiliary - 80 l. With.
The crane's pontoon contains residential and service spaces and a fuel tank. The crane is serviced by a team of 19 people. during three-shift work.
The crane in sea port construction, due to its relatively low lifting capacity and the lack of its own power, is used as an auxiliary crane in combination with a crane of higher lifting capacity and in a water area closed from waves. It is also suitable for construction of river port facilities - it is convenient for them to load T-shaped and rectangular reinforced concrete sheet piles and shells with a diameter of 1.6 m and a length of up to 16 m. With the help of such a crane and a floating conductor, embankments (from T-shaped sheet piles) with a length of over 1 km in Ust-Donetsk port.
In addition, the crane can be used in bridge construction for loading shells, installing frames and mounting supports within the limits of its load characteristics.
The disadvantage of the crane is its high height in the transport position - 18 m from the water horizon. However, it can be reduced to 12 m by dismantling the mounting structure of the fixed boom blocks.
The self-propelled 50-ton crane "Bleichert" (GDR) was widely used in the seaports of the USSR for loading, unloading and construction work.
The crane is full-rotating, equipped with three independent lifting hooks: the main one with a lifting capacity of 50 tons, an auxiliary one with a lifting capacity of 10 tons, which can be replaced by a grab, and a second auxiliary hook with a capacity of 5 tons, moved on a trolley along the bottom of the boom (“cat”).
Hooks of various lifting capacities give the crane versatility and efficiency, since small loads are handled by hooks of low lifting capacity without wasting unnecessary power on idle operation of the main cargo winches.
The crane boom has a lattice design with a pulley system for changing the reach. The engine room with lifting mechanisms, control panel, boom and permanent counterweight is located on a rotating platform, which rotates around an axial rotary axle on rollers connected by a cage. The rollers roll along a crown mounted on a beam cage on top of the pontoon deck.
The total power of electric motors for cargo operations and turning is 300 kW; DC voltage 220 V. The vessel's hull is equipped with three diesel engines (one is a reserve one) with a capacity of 150 hp each. With. each, which operate on DC generators and propeller shafts.
Operating with a crane is allowed at temperatures not lower than -25°. The team consists of 22 people. during two-shift work.
According to its characteristics, the crane can be used in the construction of sea and river berths from prefabricated standardized reinforced concrete elements. In bridge construction, the crane is suitable for work on immersing shells, installing block supports and installing elements of prefabricated reinforced concrete spans.
The excessive bulkiness of the crane (weight 543 tons, width of the pontoon 20 m, height of the crane in the transport position 15 m) limits its passage through inland waterways only of the 1st class, and then only during low water conditions.
Rice. 8. Diagram of the self-propelled floating 50-ton crane “Bleichert”: 1 - grab (or hook); 2 - “cat”; 3 - jib pulley; 4 - stop of the minimum overhang limiter; 5 - control; c - installation crane; 7- machine room; 8 - counterweight; 9 - rotary roller device; 10 - rack for laying the boom
The domestically produced full-rotating floating 50-ton crane, like the Bleichert crane described above, is equipped with three independent lifting hooks: the main one with a lifting capacity of 50 tons, and the auxiliary Yuti hook on the “cat” - 5 tons.
The crane's engine room with boom, counterweights and control panel is located on a roller turntable placed on a stand 5.4 m high from the pontoon deck. This created a significant under-jib clearance, necessary for cargo and shipbuilding work, for which purpose the crane was designed.
A special feature of the crane is the very rational design of the boom and metal structures of the crane. The boom in the form of a triangular braced truss is held by a boom pulley and a 40-movable double-action counterweight, which on large
during flights, it creates a force on the boom that is the opposite of the load moment, and thereby lightens the load on the boom winch. At short reach distances, the counterweight force corresponds to the load moment, due to which the boom is kept from tipping towards the counterweight, which is especially important when there is rough seas and there is no load on the hooks. The metal structures of the crane are made of separate large sections, taking into account the requirements of quick installation and dismantling.
Rice. 9. Scheme of a full-rotating floating 50-ton crane: 1-cable pulley for changing the boom radius; 2 - control panel; 3- counterweight; 4-stand; 5 - rack for laying the boom
In the transport position, the crane boom is lowered along the pontoon onto the stand, however, due to the high location of the engine room and the fastening of the boom fixed blocks, the height of the crane is about 26 m from the water horizon. When disassembling the mechanism for changing the boom reach, the height is reduced to 17 m.
Self-propelled twin-screw crane. The power plant consists of two ZD-6 diesel engines and DC generators with a capacity of 100 kVA each. In addition to them, there is a backup engine. Independent electric motors are installed for all movements and propellers. The power plant is located in the pontoon body where there are also rooms for the crew, household and service needs. The crane is equipped with automatic reach and load capacity indicators. Crane weight 422 t.
The full-rotation crane can be successfully used in the construction of offshore hydraulic structures.
Floating 60-ton crane from Dravo (USA), manufactured in 1941 - 1945. full-rotating non-self-propelled with a boom in the form of a spatial truss with a triangular lattice. Changing the boom radius is done using a pulley system. The boom is equipped with two hooks with a lifting capacity of 60 and 15 tons. The latter can be replaced with a grab.
The crane's engine room with a boom mounted on top, a control cabin and a counterweight rotates on a roller turntable resting on the pontoon deck. An Atlas diesel engine with a power of 275 hp is used as the primary engine. With. On many cranes these diesel engines are replaced by domestic ones. The crane control is pneumatic. The movement of the crane during operation is carried out by electric pins installed at the corners of the pontoon. The welded hull is divided by a network of watertight bulkheads. Inside the pontoon there are auxiliary, residential and service premises.
Rice. 10. Diagram of the floating 60-ton crane “Dravo”: 1 - jib pulley; 2 - crane operator's cabin; 3 swivel roller ring; 4 - rack for laying the boom
In the stowed position, the crane boom is lowered along the pontoon onto a stand. However, due to the high mounting position of the fixed boom blocks, the transport height of the crane from the water is about 22 m. After partial disassembly, the height of the crane can be reduced to 16 m.
Cranes of this type are very simple in design, easy to operate and can be successfully used in offshore construction in water areas protected from waves.
The disadvantages of the crane include the large transport height and large width of the pontoon (18.8 m), which limits its use in river construction (passage through inland waterways is only class 1, and then only with partial disassembly of the upper structure).
A floating full-rotating 60-ton crane (domestic project) has two hooks: a main hook with a lifting capacity of 50-60 tons and an auxiliary hook with a lifting capacity of 15 tons, which can be replaced with a grab.
The crane boom (Fig. 11) is shaped like a triangular pyramid and consists of three belts of solid section connected by ties. Changing 110 boom radius is done with a cable pulley. The boom has a movable counterweight. The lower swivel joint of the boom is located at a height of 14 m from the water level, which provides a large under-boom clearance necessary for loading cargo onto high-sided vessels. The crane's engine room with lifting mechanisms, movable and fixed counterweights, a boom and a control panel is located in the stern of the vessel and rotates on a column (on vertical and horizontal bearings). As an energy source, two diesel generators DGR-300/500 with a power of 300 kW each and an alternating current voltage of 380 V are installed in the vessel’s hull.
Rice. 11. Scheme of a full-rotating floating 60-ton crane (domestic project): 1 - boom pulley; 2 – support bearing of the central column; 3- crane control panel; 4-way cabin of the vessel; 5 - boom stand; 6 - winged engines; 7 - crane machine room; 8 - movable boom counterweight
The crane is designed for offshore operating conditions with waves up to 2-3 points and winds up to 6 points. The crane vessel has ship contours and moves at speeds of up to 11 km/h, having high maneuverability.
In the transport position, the crane boom is lowered onto a stand and positioned along the deck. In this position, the height of the crane from the water horizon is about 21 m. By partially dismantling the fastening structure of the fixed boom blocks and lowering the boom itself, the transport height can be reduced to 14.5 m. During sea crossings, the crane can move under its own power with waves not exceeding 3 points and wind up to 5 points. The crane can be towed without disassembly in sea conditions of no more than 5 points and winds of 6 points.
The displacement of the crane in transport position is 1080 tons. The crane team consists of 14 people. for two-shift work. The crew quarters, located in the hull of the vessel, are equipped with an air conditioning system and are finished in plastic. The crane vessel is equipped with mooring and anchor devices, fire-fighting and rescue equipment in accordance with the standards of the USSR Maritime Register.
According to their characteristics, universal floating cranes with a lifting capacity of 30-60 tons are widely used in the practice of seaport construction.
Universal cranes with lifting capacity 90 - 100 t
A floating crane from Dravo (USA) with a lifting capacity of 90 tons (Fig. 12) on the main hook and 20 tons on the auxiliary hook. The diesel-electric crane is non-self-propelled and is similar in design to the 60-ton crane of the same company described above, but has slightly larger dimensions. The power plant is represented by two diesel generators of 125 kW each.
Rice. 12. Floating 100th crane of the Dravo company: 1 - pontoon; 2-control panel; 3- arrow; 4 - main 90-ton hook; 5 - auxiliary hook; b - rack for laying the boom; 7 - jib for fastening fixed boom blocks
The height of the crane in the transport position is about 22 m, which makes it difficult to use on inland waterways and limits its use only to the construction of marine hydraulic structures.
Floating crane "Hans" built in 1949 (plant named after Georgiou-Dezh, Hungary) with a lifting capacity on the main hook of 100 tons on an auxiliary hook of 35 tons at all boom radii.
The crane boom, 35 m long, has a through structure and is fixed on! hinge at a height of 13 m from the pontoon deck. Departure change! The booms are made using two screws driven by electric motors. The use of a grab is not provided.
Rice. 13. Diagram of the floating 100-ton crane “Hans” built in 1949: 1 - boom; 2 - control cabin; 3- support roller bearing; 4 - central column; 5 - counterweight; 6 - screws for changing boom radius
The rotating part of the crane is located in the form of a dome on a pyramidal column 8.5 m high from the deck, on which the entire rotating part of the crane is put on. At the bottom of the column at the deck level there is a rotating circle, and on the rotating part of the crane there are gear rotation gears.
The crane engine room, counterweight, boom and control panel are located on the rotating part of the crane.
The all-welded hull of the vessel (pontoon) is equipped with two 100 liter diesel engines. With. with DC generators and 24 hp auxiliary diesel. With. with a generator for working in a parking lot. The pontoon contains living and living quarters for the crew, as well as tanks for fuel, fresh water, etc. The crane is self-propelled and has two screws. For mooring operations, four electric capstans are installed at the corners of the pontoon. The crane boom does not lower onto the pontoon and in the transport position is inclined at an angle of 25° to the horizon.
The main purpose of the crane is the completion of ships and loading of heavy cargo, and therefore a high boom clearance is provided. Due to the low speed of operations, the crane is ineffective when installing prefabricated structures and can be more successfully used when loading reinforced concrete elements and masses onto floating vessels at factories and landfills. It is also advisable to use the crane in cases where you have to deal with particularly long, but relatively light structures, since the lifting height above the water for a 35-hook is 40 m. Due to its bulkiness, the crane cannot be used for river construction purposes, as well as in the field of bridge construction.
The Hans floating crane, built in 1956 from the same plant as the previous crane, has a lifting capacity of 100 tons on the main hook and 25 tons on the auxiliary hook. The boom of the crane is of an articulated type with a lattice structure and has a jib moving in the opposite direction of the boom, due to which the load hooks are almost at the same height at all outreaches. The boom radius is changed by a screw system with partial balancing by a movable counterweight.
Rice. 14. Diagram of the 100-ton floating crane “Hans” built in 1956: 1 - screw mechanism for changing the boom radius; 2 – movable counterweight 124 t; 3- machine room; 4 - support column; 5 - control panel
The rotating part of the crane is designed similarly to the 1949 type crane described above. The all-welded pontoon of the crane is divided into 15 compartments by waterproof bulkheads, which ensures that the crane is unsinkable even when two compartments are filled with water. Two 160 hp diesel engines installed inside the pontoon serve as the energy source. With. with DC generators and two auxiliary diesel generators of 24 liters each. With. every. The crane has two screws driven by electric motors with a power of 100 kW each. Movement over short distances is carried out using electric pins.
In the transport position, the crane boom does not fit, so the windage and surface dimensions of the crane are very large.
According to its characteristics, the 100-t crane "Hans" (1956), in comparison with other described 100-t cranes, is the main one for the construction of sea berths, breakwaters and shore protection structures, although by its design it is more suitable for shipbuilding and loading and unloading operations .
At the same time, the Hans crane has insufficient lift height of the main and auxiliary hooks, which at working outreaches, taking into account roll, is about 25 m, which is not enough to insert 24 m long shells into the guides, which are widely used in hydraulic engineering practice. The relatively low power of the engines and the large windage of the crane require the use of tugs with a capacity of 400-500 hp for its movement even in closed port waters. That is, which sharply increases the cost of machine shifts for crane operation. The inability to transport the crane along inland waterways from one sea basin to another and to operate it on rivers and reservoirs are also among its disadvantages. The absence of a grab does not allow the crane to carry out underwater dredging of soil, which is necessary when constructing bank protection structures in open water areas and in a number of other cases.
Serves the crane (due to lack of remote control) team of 22 people. during two-shift work.
Unique floating cranes
Unique ones include universal cranes, characterized by significant lifting capacity, reaching 250 - 350 tons. Such, for example, are the cranes of the Krasnoe Sormovo plant and the Demag company.
The lifting capacity of the main hook is 250 tons, the auxiliary hook is 140 tons. In addition, a “cat” with a hook with a lifting capacity of 10 tons moves along the crane boom.
The crane is full-rotating at all loads. The crane's boom, 72 m long, consists of three powerful chords with a triangular lattice and cross braces along the lower chord. Changing the boom radius is carried out by two 16-thread pulleys. The boom has a movable counterweight that prevents it from oscillating when pitching. The boom is fixed at a height of 24.5 m from the deck, which provides a large under-boom clearance and a large lifting height of the hooks.
The upper structure of the crane with the engine room, counterweight, boom and control panel can be rotated on a column mounted in the hull of the vessel.
The two vessels of the crane are connected by a catamaran-type bridge for greater stability, since the crane is designed to work in the open sea, while its own weight reaches 2080 tons.
The crane is located on the left ship; On the right vessel there are two diesel-electric power units with a capacity of 4400 kW/l, serving the ship's movement mechanisms, and one 1500 kW for the crane mechanisms. There are also cargo holds, water and fuel supplies. The twin vessel system allows for a large cargo deck area, necessary for transporting spatial structures of oil rigs, etc., and also provides high seaworthiness compared to single pontoons of floating cranes. Thanks to its great stability, operation with a crane is allowed in waves up to 4-5 points (wave height up to 3 m) and wind force 6 points, and movement - in waves up to 6 points (wave height up to 6 m) and wind force up to 8 points.
Rice. 15. Diagram of a floating self-propelled 250-ton crane on twin vessels: a - working positions; b - transport position; 1 - boom pulley; 2 - movable boom counterweight; 3 - crane machine room; 4-central column; 5 - pilothouse; 6 - crane control panel; 7 - support bearing; 8 - boom stand
Propellers located at the stern and bow of each vessel provide the crane with high maneuverability, necessary for precise positioning at work sites. During transitions, the crane is controlled from the pilothouse, located at a height of 13 m from the deck. In the stowed position, the crane boom is lowered and positioned at an angle to the longitudinal axis of the vessel, securing it to a stand on the bow of the starboard vessel. For docking, ships are separated and docked independently of each other. The crane is equipped with a warning alarm and protective devices against overloads exceeding the calculated ones. Remote and automatic systems are used to control the crane.
Crew cabins and service areas located in the hull of the ship are provided with air conditioning, hot and cold water and other amenities.
The floating self-propelled crane 350 from Demag was built in Germany in 1938-1940. Based on its lifting capacity, size and engine power, this crane is also one of the largest floating cranes in the world.
The lifting system consists of two 175-ton main lift hooks, united by a traverse, two 30-ton auxiliary lift hooks, moved on a trolley along the boom beam (jib), and a 10-ton cat-type hook moving along the boom.
The crane is full-rotating at all loads. The crane's boom, about 80 m long, has an articulated structure, has two encircling rocker arms and a movable counterweight weighing 200 tons. The boom radius is changed using a screw mechanism. The rotating part of the crane is mounted in the shape of a bell on a pyramidal column fixed in the pontoon body. The support roller bearing at the head of the column, on which rotation occurs, has a diameter of 2.5 m and can withstand a load of 2100 tons.
The crane's engine room is three-story with a permanent 400-ton counterweight, boom and control panel located on the rotating part of the crane. The vessel's hull - a pontoon - is divided into 35 compartments by waterproof partitions. On the deck there is a platform for cargo measuring 20x26 m. For the movement and maneuverability of the crane, three water propellers of the Voith-Schneider system are installed - two at the stern and one at the bow of the vessel. For mooring operations, electric spiers are provided at the corners of the pontoon.
Rice. 16. Floating self-propelled 350-ton crane from Demag: 1 - boom tip; 2 – boom rockers; and a movable 200-ga counterweight; 4 - screw mechanism for changing the boom radius; 5 - three-story engine room with 400 counterweight; 6 - rotary mechanism; 7 pyramidal support column; 8 - control panel
The central power plant, located inside the pontoon, consists of three diesel generators with a capacity of 800 kW each and an auxiliary diesel generator of 225 kW of alternating current. There are also cabins for 23 people. teams, storage and service premises and a workshop.
The total weight of the crane is 5000 t, the height from the water horizon with the boom raised is about 115 m, and the load moment is 10,500 tm.
The main purpose of the crane is shipbuilding and ship lifting. It can also be used for construction purposes.
In total, several cranes of this type were built, one of which is in operation in the USSR on the Baltic Sea.
Floating cranes abroad
In foreign practice, in recent years, a number of very advanced floating cranes have been built, intended both for the purposes of offshore hydraulic engineering construction and for carrying out transport work.
A floating crane from Hokodate Doc (Japan) with a lifting capacity of 50 tons was built in 1962 for the construction of ports.
The boom of a flat type crane consists of two branches connected by links. In addition to the main hook, the boom has a second hook with a smaller lifting capacity. Changing the arrow's reach is done using poly-spastic. In the transport position, the boom is laid along the pontoon on a stand located at the stern.
Rice. 16. Diagram of a floating crane from the Hokodate Dock company with a lifting capacity of 50 tons: 1 stand for laying the boom; 2 - room for diesel generators; 3 - mooring winches; 4 - room for lifting mechanisms; 5 - control panel
The engine room with lifting winches, control panel, counterweights and boom rotates on paired balancing rollers moving along a ring mounted on the pontoon deck.
Self-propelled diesel-electric crane with two diesel engines of 180 liters each. With. each located in the deck superstructure. There are also crew quarters, a galley and a shower room. The pontoon body is equipped with electric winches and mooring arrangements for moving the crane over short distances.
The same company built a non-self-propelled floating crane of a similar design, but slightly smaller in size and with a lifting capacity of 30 tons.
The Samson floating maneuverable crane with a lifting capacity of 60 tons was built by Covano Sheldon and Co. in Carlisle (England).
Diesel-electric full-rotation crane with a screw mechanism and a moving counterweight to change the boom reach, with independent motors for each mechanism.
The crane body is all-welded with ship contours, divided into nine waterproof compartments. At the stern, the deck is reinforced to accommodate cargo with a total weight of 200 tons.
The crane is equipped with a high-speed auxiliary winch and a second hook with a lifting capacity of 20 tons, respectively, with a larger radius of action than the main lift hook. Electric control, performed according to the Ward-Leonard system, allows you to increase the speed of the main lift of the crane for processing loads below the maximum weight.
Rice. 17. Floating maneuverable crane "Samson" with a lifting capacity of 60 tons: 1 - auxiliary 20-ton lift; 2- main 60-meter climb; 3 - screws for changing the boom reach; 4-boom movable 81 – t counterweight; 5 - engine room with a fixed 128 t counterweight; 5 – control panel
A special feature of the Samson design is a maneuverable device in the bow, consisting of a large centrifugal pump, sucking water from under the body and throwing it out to any side depending on the direction of rotation. Together with two stern propellers located parallel at a distance of 10.4 m from each other and two streamlined rudders, this device provides maximum maneuverability to the crane even at low speeds and allows it to stop accurately at berths and move without a tug.
The upper structure of the crane is mounted on a rotating frame, on which the supporting elements of the boom, lifting mechanisms and a 128-ton counterweight are also located. The boom is lifted by two synchronously operating augers with tape threads. The lifting screws are completely covered with steel sliding covers to protect them from rain and dirt. The boom does not lower to the deck and therefore the smallest transport height of the crane is 40 m.
The main and propulsion engines consist of two 900 hp diesel engines. With. each connected to the main and additional DC generator. The power of additional generators is designed to ensure the operation of the entire crane, even with some reserve.
Due to its high navigability, the crane is suitable for working in open waters during the construction of jetties, breakwaters and bank protection structures.
Rice. 18. Diagram of a 100-ton floating crane from Ornstein Koppel: 1 - boom; 2 – control panel; 3 - wheelhouse; 4 - rotary mechanism; 5 - engine room with a fixed counterweight; 6 - mobile counterweight; 7 - support bearing
The floating 100-/I crane from Ornstein Koppel (Germany) is equipped with two main hooks with a lifting capacity of 50 tons each (Fig. 62). Both hooks are united by a common traverse. The hook lifting mechanisms work synchronously. In addition to the main ones, there is an auxiliary hook with an independent lifting winch.
The boom of the crane has a lattice structure and is 42 m long. The boom reach is changed by two screws driven by an electric motor. The weight of the boom is significantly balanced by a 40-ton movable counterweight hinged to it. Half of the overturning moment of the working load is balanced by a 164-ton counterweight located behind the engine room.
The upper rotating part of the dome-shaped crane is supported by a roller bearing on a support column fixed in the hull of the vessel. Attached to the bottom of the column is a rotating circle with a toothed gear, which allows the top of the crane to rotate 360°.
The all-welded hull of the vessel houses two diesel engines with a capacity of 200 hp each. With. at 750 rpm. The diesel shafts are connected at one end to three-phase current generators with a power of 130 kW, synchronously operating the lifting mechanisms, and at the other end - to the propeller shafts. For work in the parking lot there is an additional diesel generator set of 90 kW. The crane is equipped with devices for indicating the weight of the load, the reach and height of the load hook.
In the transport position, the boom is lowered to a horizontal position and secured to the support stand, while the windage and height of the crane are sharply reduced, thanks to which it can be transported without dismantling by tow at sea even in strong seas, which was confirmed when the crane moved to its destination, from Hamburg to the Iraqi port of Basra.
According to its characteristics, the crane is very convenient for servicing offshore hydraulic engineering.
A floating crane from Krupp (Germany) with a lifting capacity of 150 tons on the main hook and 30 tons on the auxiliary hook.
The articulated boom of the crane is made in the form of a metal structure with solid walls, which gives the crane a modern appearance.
The slewing structure [and the load balancing system are the same as those of the above 100-yard crane from Ornstein Koppel. To move over long distances, the crane boom is lowered to a horizontal position using a special screw device. The vessel hull (pontoon) is all-welded. The power plant consists of two main 500 liters. With. and two auxiliary diesel engines of 156 liters each. e., associated with current generators. The crane vessel is driven by two diagonally located propellers of the Voith-Schneider system. The pontoon deck provides the ability to load cargo with a total weight of up to 300 tons.
The crane is intended mainly for loading and unloading operations in ports and for shipbuilding needs. It can be used in offshore hydraulic engineering construction, but only in ports in closed water areas, since the significant height of the crane in the transport position (about 30 m) creates a large windage and makes it difficult to maneuver the crane in wind and waves.
Rice. 19. Floating 150-ton crane from Krupp
The floating 250-ton crane from Ornstein Koppel (Germany) was built for the port of Buenos Aires (Brazil) in 1956-1958.
The crane has two main hooks with a lifting capacity of 125 tons each, united by a traverse for lifting loads with a total weight of up to 250 tons, and two auxiliary hooks with a lifting capacity of 40 and 10 tons. The latter moves along the boom on a “cat”.
Rice. 20. Floating 250-ton crane from Ornstein Koppel
The crane operates as a full-rotating crane with a load of up to 150 tons, while changing the radius of the boom with a load is allowed. With a load of 150 to 250 tons, it is possible to rotate the crane only 22°30’ in both directions from the longitudinal axis without changing the radius of the boom with the load. The maximum load moment of the crane is 5125 m.
The upper structure of the crane with boom, machine room with lifting winches, counterweights and control panel rotates on a powerful axial roller bearing operating in an oil bath. The bearing is mounted on a pyramidal column fixed in the pontoon. Horizontal forces from the crane's upper structure are transmitted to a horizontal bearing consisting of a ring with a diameter of 5.7 m and eight rollers combined in pairs. This device greatly facilitates turning, but increases the dimensions of the crane and is used, as a rule, in cranes in Germany with a lifting capacity of over 100 tons.
The boom of the crane has a lattice structure and is riveted. Changing the boom radius is carried out by two pulleys. The boom is partially balanced by a counterweight.
The crane is non-self-propelled and is moved by four drive capstans with a force of 6 tons and a rope retrieval speed of 12 m/min. Due to the lack of its own power, the crane’s power plant consists of only two diesel engines with a capacity of 185 and 260 hp. With. and three DC generators 2×110 + 60 kW with a voltage of 230 V. For our own needs, the parking lot has an auxiliary diesel generator with a capacity of 22.5 liters. With. All nine crane electric motors are of the same type with a power of 44 kW each at 750 rpm.
The crane is controlled from a central console located at a height of 14 m from the deck. Provided automatic devices, eliminating overloading of the crane, and electrical blocking in case of incorrect actions by the crane operator.
The crane's pontoon is welded and divided into 18 compartments by waterproof partitions. On the deck of the pontoon there is a platform of 9.5×9.5 for accepting cargoes of up to 10 t/m2. Inside the pontoon there are diesel generators and living cabins for 12 people. crew, household and storage facilities and a workshop.
In the transport position, the crane boom is lowered to the deck with its own pulleys and secured, and the upper structure is wedged with hydraulic jacks, which relieves the axial bearing. In this form, the crane can be towed by sea at a speed of 5-7 knots (up to 13 km/h). The height of the crane in transport position is about 32 m from the water horizon.
This crane is intended for transport work, but can also be successfully used for the construction of breakwaters, berths and piers from large-sized elements and heavy masses.
3. Floating cranes
As cranes for hydraulic engineering and bridge construction, floating pile drivers with inclined booms can be used, the reach of which over the side of the pontoon can be in the range from 3 to 9 m with a corresponding lifting capacity of 30 and 10 tons. Turning the pile driver boom on board in many cases is not allowed, Therefore, pile driver cranes are usually non-rotating.
In this area, the most common are piledrivers with swinging arms, for example, the CCSM-680 type piledriver from Nillens, etc.
The SSSM-680 type pile driver, installed on a pontoon, can be used as a floating crane when the boom is positioned along the pontoon at radii of up to 9 m from the end of the pontoon. The pile driver is not self-propelled. The energy source is a steam boiler with a heating surface of 50 m2 at a steam pressure of 6-8 kg/cm2. Load-lifting mechanisms - steam winches.
Mooring operations are carried out using manual winches. Inside the pontoon there are living and utility rooms for 10 people. copra teams.
In the transport position, the boom is rotated and placed along the pontoon on a stand.
The floating pile driver from Nillens (Belgium) is non-self-propelled. The boom is located in the bow of the pontoon on a platform that rotates 180°. Crane operation and pile driving are allowed only when the boom is positioned along the pontoon. In this case, the maximum reach of the boom from the end will be 6.5 m.
Rice. 21. Installation diagram of a pile driver from the Nillens company: a - for working with a pile driver; b-for working with a crane; 1-truss with boom; 2-double-drum winch; 3- steam boiler; 4 - pontoon; 5 - steam hammer; 6 - stand for laying the boom; 7-ballast water tanks
All mechanisms of the pile driver are steam and are provided with steam from the boiler with a pressure of 8 kg!cm2. The boiler is located on a rotating platform and is also a counterweight to the boom and hammer. To bring the pile driver into the stowed position, the rotating platform with the boom and boiler is rotated 180° and the boom is lowered using a special mast and pulley onto a stand located at the stern of the pontoon. The pontoon has ballast compartments, fresh water tanks and storage areas. Crew cabins are located on deck. During operation, the pile driver moves on the mooring ends using winches and bollards.
The floating pile driver of the Ubigau plant (GDR) is the most modern. The swinging boom of the piledriver together with the steam boiler (heating surface 34 l2 and pressure up to 10 kPcm) is located on a turntable rotating 360° (in the bow of the pontoon). The piledriver boom can tilt forward 1/10 when positioned across the pontoon and 1/3 along the pontoon.
Steam only powers the hammer when driving piles; the rest of the mechanisms are electrically driven by a diesel generator with a capacity of 57 kW. In addition, there is an auxiliary diesel generator of 12 kW for its own needs when parking.
The pile driver is not self-propelled. In the transport position, the boom is rotated 180° and lowered with a special mast along the pontoon onto a stand.
The headframe pontoon contains fresh water tanks, ballast compartments, a fuel bunker and storage areas. The pontoon is equipped with mooring devices and crew accommodation.
TO Category: - Cranes for bridge construction
Floating crane is a lifting crane installed permanently on a special vessel, both self-propelled and non-self-propelled, and designed to perform lifting and reloading operations.
2.1.1. General information
Unlike other types of cranes, floating ones have living quarters for the crew (permanent crew), repair and rigging shops, canteens, additional ship equipment, deck mechanisms, and their own power plants, allowing the crane to operate autonomously away from the shore. The mechanisms of floating cranes are usually diesel-electric driven. It is also possible to supply electricity from the shore. Propellers or winged propellers are used as propulsors. The latter do not require a steering device and can move the crane forward, backward, sideways (lagging) or deploy on the spot.
Depending on the waterways, floating cranes are subject to the jurisdiction of the Russian Maritime Register of Shipping or the Russian River Register.
In accordance with the requirements of the Maritime Register, floating cranes must be equipped with all devices provided for ships, i.e. must have fenders ( wooden beams, protruding along the outer part of the freeboard of the ship continuously or in parts, protecting the side plating from impacts against other ships and structures), spiers (ship mechanisms in the form of vertical gates for lifting and releasing anchors, lifting weights, pulling mooring lines, etc.), bollards ( paired pedestals with a common plate on the deck of the ship, designed for attaching cables to them), anchors and anchor winches, as well as light and sound signaling equipment, radio communications, sump pumps and life-saving equipment. During operation, the floating crane must have a supply of fresh water, food, fuel and lubricants in accordance with the standards for the duration of autonomous navigation. The main requirements for floating crane pontoons are structural strength, buoyancy and stability.
In the case of transportation along inland waterways, the overall height of the crane in the stowed state must comply with GOST 5534 and be assigned taking into account the scaffold dimensions and the possibility of passing under overhead power lines.
According to their purpose, cranes can be classified as follows:
Reloading cranes(general purpose), intended for mass handling operations (their description is presented in works). According to GOST 5534, the lifting capacity of floating reloading cranes is 5, 16 and 25 tons, the maximum reach is 30...36 m, the minimum is 9...11 m, the height of the hook above the water level is 18.5...25 m, the depth of lowering below the water level (for example, into the ship's hold) - not less than 11...20 m (depending on the carrying capacity), lifting speed 1.17...1.0 m/s (70...45 m/min), speed of change of departure 0.75...1.0 m /s (45...60 m/min), rotation speed 0.02...0.03 s -1 (1.2...1.75 rpm). These are cranes such as, for example, “Gantz”, made in Hungary (Fig. 2.1.), domestic cranes (Fig. 2.2).
Special purpose cranes(high lifting capacity) - for reloading heavyweights, construction, installation, shipbuilding and rescue work.
Floating cranes designed for installation work are used in the construction of hydraulic structures and for work at shipbuilding and ship repair yards.
A crane from the German company Demag with a lifting capacity of 350 tons was used during the reconstruction of Leningrad bridges, during installation
80-ton gantry cranes, when moving gantry cranes from one port area to another, etc.
Crane of the PTO plant named after. S. M. Kirov with a lifting capacity of 250 tons was manufactured for the installation of oil rigs on the Caspian Sea.
The Chernomorets cranes with a lifting capacity of 100 tons and the Bogatyr cranes with a lifting capacity of 300 tons (Fig. 2.3) were awarded the USSR State Prize.
Rice. 2.2. Reloading floating cranes with a lifting capacity of 5 tons ( A) and 16 tons ( b): 1 – grab at maximum reach; 2 – trunk; 3 – traveling arrow; 4 – emphasis; 5 – working boom; 6 – pontoon; 7 – grab at minimum reach; 8 – cabin; 9 – rotating support; 10 – column; 11 – balancing device combined with a mechanism for changing the reach; 12 – counterweight
Rice. 2.3. Floating crane “Bogatyr” with a lifting capacity of 300 tons (Sevastopol plant named after S. Ordzhonikidze): 1 – pontoon; 2 – traveling arrow; 3 – auxiliary lift suspension; 4 – main lift suspension; 5 – boom
The Vityaz crane (Fig. 2.4) with a lifting capacity of 1600 tons is used when working with heavy loads, for example, when installing on supports of bridge structures across a river mounted on the shore. In addition to the main hoist, this crane has an auxiliary hoist with a lifting capacity of 200 tons. The reach of the main hoist is 12 m, the auxiliary hoist is 28.5 m. There are floating cranes with a larger lifting capacity.
Special cranes that perform reloading of heavyweights in ports, installation and construction work during the construction of ships, ship repair and construction of hydroelectric power stations, emergency rescue operations, have fully revolving top structures. Load capacity - from 60 (Astrakhan crane) to 500 tons, for example: Chernomorets - 100 tons, Sevastopolets - 140 tons (Fig. 2.5), Bogatyr - 300 tons, Bogatyr-M - 500 tons . In Fig. 2.6 shows Bogatyr cranes with various modifications of booms and corresponding graphs of lifting capacity, variable by reach.
Specialized cranes for ship-lifting and rescue operations and installation of large-sized heavy structures, as a rule, are non-rotating.
Rice. 2.5. Floating crane “Sevastopolets” with a lifting capacity of 140 tons (Sevastopol plant named after S. Ordzhonikidze): 1 – pontoon; 2 – traveling arrow; 3 – boom in working style
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Rice. 2.6. Floating cranes: A- “Bogatyr”; b– “Bogatyr-3” with an additional boom; V– “Bogatyr-6” with an extended additional boom; Q– permissible load capacity at reach R; N– lifting height
Examples of such cranes are: “Volgar” - 1400 tons; “Vityaz” - 1600 tons (Fig. 2.4), lifting a load weighing 1600 tons is carried out using a winch of three deck hoists, “Magnus” (Germany) with a lifting capacity from 200 to 1600 tons (Fig. 2.7), “Balder” , Holland) with a lifting capacity from 2000 to 3000 tons (Fig. 2.8).
Oilfield. Crane vessels for the supply of offshore oil fields and the construction of oil and gas field structures on the shelf usually have rotating topsides, significant reach and lifting height, and are capable of servicing stationary drilling platforms. Such cranes include, for example, “Yakub Kazimov” - with a lifting capacity of 25 tons (Fig. 2.9), “Kerr-ogly” - with a lifting capacity of 250 tons. In connection with the development of the continental shelf, there is a tendency towards an increase in the parameters of cranes of this group (load capacity - up to 2000...2500 tons and more).
Rice. 2.7. Floating crane "Magnus" with a lifting capacity of 800 tons (HDW, Germany): 1 – pontoon; 2 – traveling arrow; 3 – deck winch; 4 – jib tilt winch; 5 – strut; 6 – boom; 7 – jib; 8 – main lift suspension; 9 – auxiliary lift suspension
Rice. 2.8. Floating crane "Balder" with a lifting capacity of 3000 tons ("Gusto", Holland - ( A) and a schedule for changing the permissible load capacity Q from departure R (b)):
1 – pontoon; 2 – rotating platform; 3 – boom; I…IV – hook hangers
Rice. 2.9. Crane vessel “Yakub Kazimov”: 1 – pontoon; 2 – traveling arrow; 3 – leveling tackle; 4 – cabin; 5 – rotating part frame
Depending on seaworthiness, taps can be classified as follows:
1) port (to perform transshipment work in ports and harbors, closed reservoirs and coastal sea (coastal) and river areas, at shipbuilding and ship repair yards);
2) seaworthy (for work on the open sea with the possibility of long independent passages).
The domestic crane industry is characterized by the desire to create universal cranes, and the foreign industry - highly specialized cranes.
2.1.2. Construction of floating cranes
Floating cranes consist of a top structure (the crane itself) and a pontoon (a special or crane vessel).
Top structure of a floating crane, crane vessel, etc.– a lifting structure installed on an open deck designed to carry a lifting device and cargo.
Pontoons, like ship hulls, consist of transverse (frames and deck beams) and longitudinal (keel and keelson) elements sheathed in sheet steel.
Frame – a curved transverse beam of the ship's hull, providing strength and stability of the sides and bottom.
Beam– a transverse beam connecting the right and left branches of the frame. The deck is laid on the beams.
Keel- a longitudinal connection installed in the center plane of the vessel at the bottom, extending along its entire length. The keel of large and medium-sized ships (internal vertical) is a sheet installed in the center plane between the double bottom flooring and the bottom plating. To reduce pitching, side keels are installed normal to the outer hull of the vessel. The length of the side keel is up to 2/3 of the length of the vessel.
Kilson– a longitudinal connection on ships without a double bottom, installed along the bottom and connecting the lower parts of the frames for their joint operation.
The shape of the pontoons is a parallelepiped with rounded corners or has ship contours. Pontoons with rectangular corners have a flat bottom and a cut in the stern (or bow) part (Fig. 2.10). Sometimes the crane is mounted on two pontoons (catamaran crane). In these cases, each pontoon has a more or less pronounced keel and a shape similar to that of the hulls of ordinary ships. The pontoons of floating cranes are sometimes made unsinkable, i.e. equipped with longitudinal and transverse bulkheads. To increase the stability of a floating crane, i.e. ability to return from a tilted position to an equilibrium position after removing the load, it is necessary to lower its center of gravity if possible. To do this, high superstructures should be avoided, and living quarters for the crane crew and warehouses should be placed inside the pontoon. Only the wheelhouse (ship's control cabin), galley (ship's kitchen) and dining room are brought onto the deck. Inside the pontoon, along its sides, there are tanks (tanks) for diesel fuel and fresh water.
Floating cranes can be self-propelled or non-self-propelled. If the crane is intended to serve several ports or to move long distances, then it must be self-propelled. In this case, pontoons with ship contours are used. Sea-going cranes have pontoons with ship contours; a number of heavy cranes use catamaran pontoons (Ker-ogly with a lifting capacity of 250 tons; a crane from Värtsilä, Finland, with a lifting capacity of 1600 tons, etc.).
According to the design of the superstructure Floating cranes can be classified into fixed-rotary, full-rotary and combined.
Fixed(mast, gantry, with swinging (tilting) booms). Mast cranes (with fixed masts) have a simple design and low cost. Horizontal movement of cargo is carried out when moving the pontoon, so the productivity of such cranes is very low.
Rice. 2.10. Floating crane pontoon diagram
Floating cranes with tilting booms are more suitable for working with heavy weights. With variable reach, their productivity is greater than that of mast-mounted ones. These cranes have a simple structure, low cost and large lifting capacity. The crane boom consists of two posts converging to the top at an acute angle, and is hinged at the bow of the pontoon. The boom is lifted using a rigid rod (hydraulic cylinder, rack or screw device) or using a pulley mechanism (for example, on the Vityaz crane). The boom in the transport position is secured to a special support (Fig. 2.3). To perform this operation, boom and auxiliary winches are used.
A floating gantry crane is a conventional gantry crane mounted on a pontoon. The crane bridge is located along the longitudinal axis of the pontoon, and its only console extends beyond the contours of the pontoon by a distance sometimes called the outer overhang. The outer reach is usually 7...10 m. The lifting capacity of floating gantry cranes reaches 500 tons. However, due to the high metal consumption, floating gantry cranes are not produced in our country.
Full rotation(universal) cranes come with a rotating platform or a column. Nowadays, tilting boom slewing cranes are widely used. They are the most productive. Their arrows not only tilt, but also rotate around a vertical axis. The lifting capacity of rotary cranes varies widely and can reach hundreds of tons.
Full-revolving cranes include the Bogatyr crane with a lifting capacity of 300 tons and an external reach of 10.4 m with a lifting height of the main hook (hook) above sea level of 40 m, as well as the offshore transport and installation vessel Ilya Muromets. The latter has a lifting capacity of 2×300 tons at an outer reach of 31 m. The height of the crane vessel with the boom raised is 110 m. These cranes are capable of navigating seas in storms of 6...7 points and winds of 9 points. Sailing autonomy is 20 days. The speed of the Bogatyr crane is 6 knots, and the Ilya Muromets crane vessel is 9 knots. Both vessels are equipped with a set of mechanisms and devices that provide a high level of mechanization of main and auxiliary processes. In the transport position, the booms of both described vessels are placed on special supports and secured.
Combined. These include, for example, floating gantry cranes, on the bridge of which a rotary crane moves.
The predominant type of boom device for floating cranes is a straight boom with a leveling pulley; Articulated boom devices are used less frequently, but their use is associated with difficulties in stowing in a traveling manner.
To prevent the straight booms of offshore cranes from tipping over during waves, under the influence of inertia and wind forces, as well as when the load breaks and is dropped, the booms are equipped with safety devices in the form of limit stops or special balancing systems. Magnus cranes have a boom with a load held in place by a rigid strut.
As boom designs developed, a transition was made from lattice and braceless booms to solid-walled (box-shaped, less often tubular) booms in a beam or cable-stayed design. On cranes of recent years, sheet-shaped box booms are more often used. However, lattice booms of some foreign cranes with very large lifting capacities are known (Balder crane, see Fig. 2.8). When modernizing cranes, the base booms are often extended with additional cable-stayed booms (see Fig. 2.6), which makes it possible to significantly increase the maximum reach and lifting height and at the same time ensure broad unification with the base model.
The main types of slewing bearings for floating cranes are a rotating and fixed column, a multi-roller slewing ring, a slewing ring in the form of a double-row roller bearing. There is a trend towards the use of slewing rings in the form of roller bearings on cranes with a lifting capacity of up to 500 tons. On heavier cranes, multi-roller turntables are still used; work is underway to create segmented roller bearings for such cranes.
Lifting mechanisms used on floating cranes are grab winches with independent drums and differential switches. According to GOST 5534, a reduced speed for landing the grab on the load is provided, amounting to 20...30% of the main speed. It is possible to replace the grab with a hook suspension.
The turning mechanisms (one or two) often have helical-bevel gearboxes with multi-disc torque limiting clutches and an open gear or lantern drive.
The mechanism for changing the reach is sectoral with the installation of sectors on the counterweight lever or hydraulic with a hydraulic cylinder connected to the platform and a rod connected to the counterweight lever. Cranes with a screw mechanism for changing the reach are known. The designs of mechanisms for changing the reach are presented in section 1 “Gantry cranes”.
Floating reloading grab cranes in river and sea ports are used very intensively. For lifting mechanisms, the PV values reach 75...80%, for turning mechanisms - 75%, for mechanisms for changing reach - 50%, the number of starts per hour - 600.
2.1.3. Calculation features
Pontoon geometry. When designing and calculating, the pontoon is considered in three mutually perpendicular planes(see Fig. 2.10). The main plane is the horizontal plane tangent to the bottom of the pontoon. One of the vertical planes, the so-called center plane, runs along the pontoon and divides it into equal parts. The intersection line of the main and diametrical planes is taken as the axis X. Another vertical plane is drawn through the middle of the length of the pontoon and is called the midship frame plane, or midship plane. The intersection line of the main and midship planes is taken as the axis Y, and the line of intersection of the midship and center planes - behind the axis Z.
The plane parallel to the midsection plane and passing through the axis of rotation of the rotary crane is called medial. The lines of intersection of the surface of the pontoon hull with planes parallel to the midsection plane are called frames (the same name is given to the transverse elements of the vessel that form the frame of its hull). The lines of intersection of the surface of the pontoon body with planes parallel to the main plane are called waterlines. The mark of the water surface on the pontoon body has the same name.
Since a pontoon located on the water can be inclined, the resulting waterline is called active. The plane of the current waterline, non-parallel to the planes of the other waterlines, divides the pontoon into two parts: surface and underwater. The waterline corresponding to the position of the crane on the water without a load, balanced in such a way that its main plane is parallel to the surface of the water, is called the main waterline.
The tilt of the ship to the bow or stern is called trim, and the tilt of the ship to starboard or port is called heel. Corner ψ (see Fig. 2.10) between the effective and main waterlines in the center plane is called the trim angle, and the angle θ between the same lines in the midsection plane - the roll angle. When trimmed to the bow and when heeling towards the boom, the angles ψ And θ are considered positive.
Length L pontoons are usually measured along the main waterline, the estimated width B pontoon - at the widest point of the pontoon along the waterline, and the estimated height H sides - from the main plane to the side line of the deck (see Fig. 2.10). The distance from the main plane to the effective waterline is called draft T pontoon, which has different meanings at the bow of the pontoon T H and at the stern T K. Difference of values T H – T K called trim. Difference between height and draft H–T called height f freeboard. If the shape of the pontoon is not a parallelepiped, i.e. has smooth contours, then for calculations a so-called theoretical drawing is drawn up, which determines the external shape of the hull (several sections along the frames). With rectangular pontoons there is no need to draw up such a drawing.
Volume V the underwater part of the pontoon is called volumetric displacement. The center of gravity of this volume is called the center of magnitude and is designated CV. Mass of water in volume V called mass displacement D.
Stability of floating cranes. Stability is the ability of a vessel to return to a position of equilibrium after the cessation of the forces causing it to tilt.
Features of calculating the stability of floating cranes largely come down to taking into account the influence of roll and trim. The crane without a load should have a trim to the stern, and with a load - to the bow. If the boom is located in the medial plane without a load, the crane should tilt towards the counterweight, and with a load - towards the load. The change in reach due to roll or trim can amount to several meters. The design reach is taken to be the reach that the crane has when the pontoon is in a horizontal position.
For a crane with a load, the rotating part of the crane with a counterweight creates a moment that partially balances the load moment and is called balancing (see Fig. 2.10): M У = G K y K , Where G K- weight of the superstructure; yK- distance from the axis of rotation of the crane to the center of gravity of the superstructure (including counterweights).
For cranes with movable counterweights, the balancing moment is defined as the sum of the moments from the superstructure weights and counterweights.
Load moment M G = GR,Where G- weight of cargo with hook suspension; R- arrow departure. The ratio of the balancing moment to the load moment is called the balancing coefficient φ = M U / M G.
To determine the heeling and trim moments, consider Fig. 2.11, which shows the pontoon and boom in plan. Weight of the rotating part of the crane with load G K attached at a distance e from the axis O 1 boom rotation. Action of weight G K on the shoulder e can be replaced by the action of vertical force G K at the point O 1 and the moment G K e in the plane of the arrow. Pontoon weight with ballast G 0 applied at point O2. In addition, the crane is subject to a vertical moment from the wind load, which has components relative to the corresponding axes M VX And M ВY. Then the heeling moment is determined by the dependence of the form M K = M X = G K e cos φ + M BX, and the trimming moment M D = M U = G K e sin φ + M B Y.
To determine the restoring moment, consider Fig. 2.12, which shows a cross-section of the pontoon along the midsection plane in positions before and after the application of the heeling moment. The center of gravity of the pontoon crane is indicated DH. A crane at rest is subject to vertical forces having a resultant N, and buoyant force D = Vρg, Where V- displaced volume; ρ - density of water; g- free fall acceleration. According to Archimedes' law, D=N.
In a state of balance of power N And D act along one vertical, passing through the center of gravity and the center of magnitude and called the axis of swimming. In this case, the roll angle may have some significance θ (see Fig. 2.10).
Rice. 2.11. Scheme for determining heeling and trim moments
Rice. 2.12. Diagram of the pontoon position before ( A) and after ( b) application of heeling moment
Let us assume that a static heeling moment is applied to the crane M K, caused, for example, by the weight of the load G at the end of the crane boom. In this case, the center of the value shifts. By changing forces D And G in comparison with the equilibrium state can be neglected, since the weight of the load is significantly less than the weight of the crane. Then strength D in an inclined position the crane will be applied at the point CV(Fig. 2.12, b). In this case, a restoring moment of force will occur D And N=D on the shoulder l θ, equal to the heeling moment M K, i.e. , where is the transverse metacentric height, i.e. distance from the metacenter to the center of gravity.
A point is called a metacenter F intersection of the swimming axis with the line of action of the force D, and the metacentric radius is the distance from the metacenter F to the center of the value.
When trimmed at an angle ψ
the restoring moment is equal to the trimming moment M D, i.e. 
, where is the longitudinal metacentric height; a- the distance between the centers of gravity and magnitude. The products are called static stability coefficients.
Let us determine the metacentric radii and . From the theory of the ship the following is known:
1) at small roll angles θ and trim ψ metacenter position F unchanged, and the center of the quantity moves along a circular arc described around the metacenter;
2) metacentric radius R=J/V, Where J- moment of inertia of the area limited by the waterline relative to the corresponding axis around which the crane tilts.
For a crane at rest, the area limited by the waterline is equal to B.L..
For a rectangular pontoon (without taking into account contours and bevels), moments of inertia about the main axes J X = L B 3 / 12; J Y = B L 3 / 12, and the displaced volume of water V = B L T. In this case, the metacentric radii are ; 
.
Thus, the angles of roll and trim, depending on the heeling and trim moments, are determined from the expressions
; 
.
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Rice. 2.13. Floating crane stability diagrams: A– static M VK(q); b – dynamic A B(q)
For slewing cranes with an oscillating boom, these angles are variable both in terms of reach and angle of rotation.
The restoring moments during roll and trim are determined by formulas of the form:
; (2.1)
At roll angles greater than 15°, formula (2.1) is not applicable, and the righting moment M VK depending on the angle θ changes according to the static stability diagram (Fig. 2.13). With a gradual increase in heeling moment to a value equal to the maximum value of the righting moment M VK max on the diagram, the roll angle reaches θ M , and the crane will be unstable, since any accidental tilting in the direction of the roll will lead to capsizing. Application of heeling moments M θ ³ M VC max is not allowed. Dot TO(sunset diagram) characterizes the maximum roll angle θ P , when exceeded M VK< 0 and the crane overturns. The static stability diagram is included in the mandatory crane documentation; its construction according to the pontoon drawing or using approximate formulas is given in the work.
In case of sudden (or in a time less than half-period of natural oscillations) application of a dynamic moment to an unheeled pontoon M D(see Fig. 2.13, A), which subsequently remains constant, in the initial period of roll M D > M VK and the ship will roll with acceleration, accumulating kinetic energy. Having reached the static roll angle q(dot IN), the ship will heel further up to the dynamic heel angle q D, when the reserve of kinetic energy is spent to overcome the work of the restoring moment and resistance forces (point WITH, corresponding to equality of areas OAV And SVE). At q D £ 10…15 O(Fig. 2.13, A) can be considered q D = 2q(taking into account water resistance q D= 2 xq, Where x- attenuation coefficient ( x" 0.7); in the presence of an initial roll angle ± q 0 dynamic roll angle q D = ± q 0+ 2q. Overturning dynamic moment M D.OPR and tipping angle q D.OPR determined by finding a straight line AE, cutting off equal areas on the static stability diagram OAV And VME(Fig. 2.13, b).
The dynamic stability diagram (see Fig. 2.13) is a graph of the work of the restoring moment A B= D from the roll angle ( l q- righting moment arm during roll (see Fig. 2.12); it is an integral curve with respect to the static stability diagram; magnitude d B = A B / D= called dynamic stability arm. Heeling moment work A K = M D q D = D d K, Where d K = A K / D D = M D q D / D– specific work of heeling moment. Schedule A K (q D) there is a straight line OF, passing through points O And F with coordinates (1 rad, M D); Dot R intersections (see Fig. 2.13, A) or touch (see Fig. 2.13, b) diagrams of dynamic stability with a straight line OF determines the dynamic roll angle q D (A) or rollover angle during dynamic roll q D.OPR (b).
Dynamic roll (or trim) occurs when the load is lifted with a jerk or when the load breaks. In Fig. 2.14 shows the position of the water mirror relative to the pontoon for a crane without a load (equilibrium position 1 at bank angle q 0) and with a load in a static roll (position 2 at bank angle q). For normal operation of the crane, it is desirable to have equality in the absolute values of the roll angles for a loaded and empty crane. If the load breaks, the crane will oscillate relative to its equilibrium position 1 with amplitude Δ q(see Fig. 2.14), reaching the position 3 at dynamic roll angle q DIN = q 0+ Δ q. The values of the latter are more accurate if water resistance is taken into account, according to the formula
q DIN= q 0+ (0.5 – 0.7) Δ q.
Rice. 2.14. Pontoon diagram for determining dynamic roll
Determination of the overturning moment and the angle of dynamic roll in operating condition in the event of a cargo breakage according to the dynamic stability diagram, as well as checking the stability of the crane during transition, hauling, and in non-operating condition; The determination of the overturning moment in the traveling state and the maximum righting moment in the non-operating state are discussed in detail in the work.
Loads on the rotation mechanism and changes in reach. In Fig. 2.15, A shown transversely (in the plane Y) and longitudinal (in the plane X) sections of the pontoon after a roll at an angle q and trim by angle ψ .
Weight G K the rotating part of the crane with a load has components S And S X, acting in the plane of rotation and determined by dependencies of the form S Y = G K sin q And S X = G K sin ψ .
For a floating crane, the additional moment caused by roll and trim and acting on the rotation mechanism (Fig. 2.11) is determined by the formula
This expression can be explored to the maximum M φ. In particular, if the component of the trimming moment М ψ = G К a – G 0 b = 0(balanced pontoon), then the maximum M φ achieved at φ = 45 o.
Powers S X And S have components acting in the plane of swing of the boom and perpendicular to it. The components acting perpendicular to the swing plane of the boom create a moment that loads the rotation mechanism, the expression for which was obtained above. Total strength T component forces S X And S in the boom swing plane is determined by an expression of the form T= S X sin φ + S Y cos φ = G K ( sin q sin φ – sin ψ cos φ).
This force acts in the plane of swing of the boom and is directed along the pontoon. In Fig. 2.15, b weight decomposition shown G K to strength R, perpendicular to the main plane of the pontoon and taken into account in the calculations of the mechanism for changing the reach, and on the force T, parallel to the longitudinal axis of the pontoon and creating additional load caused by roll and trim. Thus, in the center of gravity of each unit of the rotating part of the crane (boom, trunk, etc.) the weight G i power arises T i caused by roll and trim. Additional point M, loading the mechanism for changing the offset, is determined by the formula .
Loads from inertia forces, acting on the crane during transverse and longitudinal pitching of the vessel, are presented in detail in the works.
Unsinkable– the ability of the ship to maintain the minimum required buoyancy and stability after flooding of one or more hull compartments. The calculation of unsinkability is presented in detail in the work.