Abstract: In embodiments, motion may be arrested and/or dampened using a motion arresting and dampening device comprising a lifting spreader bar, one or more bar mounted winches, deployment wire, a restorative inflation device, restraining wires and winches, hoses and controller, mechanical connection release system circuitry. Multiple restraints from winches mounted strategically on a vessel crane's boom may be applied to the spreader bar to restrain the bar during the lifting operation. The forces induced into the lifted object by the movement of the crane as it deploys the object into installation position are attenuated by the physical restrain of the adjustable wires. These adjustable wires may also be used to provide rotation of the object during final alignment of the object during installation.

Abstract: A modular gas turbine system is disclosed. The system includes a base plate and a gas turbine engine mounted on the base plate. The gas turbine engine is drivingly coupled to a rotating load mounted on the base plate. A supporting frame extends above the base plate. A first bridge crane and a second bridge crane are movably supported on the supporting frame.

Abstract: A method for controlling a crane component of a tower crane in proximity of obstacles at a worksite by defining a forbidden volume is disclosed. In the method a distance from the crane component to an outer surface of the forbidden volume is determined and a computing device limits movement of the crane component based on the distance from the crane component to the outer surface of the forbidden volume to avoid entering the forbidden volume with the crane component while the crane is in operation. The crane component is one or more of a boom and a hook block.

Abstract: The present disclosure relates to a stop ring (1) comprising a support eye lug (2) used to suspend a stopping or lashing means and a threaded pin (6), rotatably arranged with respect to the supporting eye lug (2), for fixing to an object to be lifted or fixed, the support eye lug (2) and the threaded pin (6) being connected to each other in a form-fitting manner by a bearing journal (5) of the threaded pin (6), which engages in the bearing bore (4) of the support eye lug (2), and a plurality of bearing rollers (8), and having a locking element (13) by means of which, in a locking position, the support eye lug (2) and the threaded pin (6) can be blocked against rotation, characterized in that the bottom (3) of the support eye lug (2) is closed at the top.

Abstract: Systems and methods are provided for least one leading drone configured to move to a leading drone future location based on a future location of a base station. A set of base station future locations may form a base station path for the base station to traverse. Also, a set of leading drone future locations may form a leading drone path for the leading drone to traverse. The base station's future location may be anticipated from a prediction or a predetermination. The leading drone, navigating along the leading drone path, may collect sensor data and/or perform tasks. The leading drone may interact with sensor drones while traversing the leading drone path. Accordingly, the leading drone may move ahead of the base station in motion, as opposed to following or remaining with the base station.

Abstract: Provided is a slow stopping apparatus for a working machine which can shorten a stopping time while suppressing a cargo swing. The slow stopping apparatus includes a first slow stopper 21 which calculates a cargo swing cycle T and takes a time T1 in a half of the cargo swing cycle T to stop an actuator 10 when a stop signal is input, a second slow stopper 22 which takes a shorter time T2 than the time T1 in the half of the cargo swing cycle T to stop the actuator 10, a cargo swing predictor 23 which predicts whether a load amplitude A would exceed an allowable value, and a switcher 24 which switches the first slow stopper 21 and the second slow stopper 22 in accordance with prediction of the cargo swing predictor 23. It is possible to suppress a cargo swing in stop of a motion of the working machine, thereby shortening a time required for stopping the motion of the working machine.

Abstract: A shovel includes a lower-part movable body, an upper-part turnable body turnably mounted on the lower-part movable body, a boom including a first end rotatably attached onto the upper-part turnable body, an arm including a first end rotatably attached to a second end of the boom, a work element rotatably attached to a second end of the arm, an electrical energy storage device including multiple electrical energy storage cells, and mounted on the upper-part turnable body, a controller configured to control the charge and discharge of the electrical energy storage device, and multiple voltage measurement parts configured to measure the respective cell voltages of the electrical energy storage cells. Information on the cell voltages is transmitted to the controller.

Abstract: A system for extraction of a pool cleaning robot from a pool, the system may include a pool cleaning robot interface that is arranged to be coupled to a pool cleaning robot during an exit process during which the pool cleaning robot is extracted from the pool; and a pool cleaning robot manipulator that is coupled to the pool cleaning robot interface, wherein the pool cleaning robot manipulator is arranged to move the pool cleaning robot interface between a first and second portion; wherein when the pool cleaning robot interface is at the first position and is coupled to the pool cleaning robot, the pool cleaning robot is within the pool; wherein when the pool cleaning robot interface is at the second position and is coupled to the pool cleaning robot, the pool cleaning robot is positioned outside the pool.

Abstract: Methods and apparatus access the boom (jib) of a crane, e.g. of the type commonly employed on offshore oil rigs. In place of the extensive scaffolding structure normally required to provide secure access to a crane boom (10) for maintenance and inspection, a carriage (11) is mounted on the boom either on a temporary or permanent basis. The carriage (11) includes a stable platform (22) or floor capable of supporting one or preferably two workers (23) to provide comfortable and safe access to the boom for e.g. a re-painting operation. The carriage (11) is supported on the boom via wheels (16) and is movable along the boom to provide access to the full length of the boom. The distal end may be of tapering section and it is preferred that the wheels (16) of the carriage are adjustably mounted to take account of the taper.

Abstract: The invention relates to a method for conducting service on a wind turbine after the wind turbine is erected and after the hub (1) of the wind turbine is mounted on the main shaft (3) of the wind turbine. The method comprises mounting of servicing equipment a crane (8) on the hub (1) of the wind turbine and lowering and hoisting wind turbine appliances from and to the hub. Thereby, it is possible to lower from and to lift to the hub, the appliances which is to be replaced or repaired without using the hatch constituting the escape way and without having to transfer the appliances through the nacelle and along the tower. The invention also relates to means (5, 6) for primarily securing the equipment to the hub of the wind turbine.

Abstract: The invention relates to an arrangement for installing cables on outer surfaces of crane structures (1), the arrangement comprising means (9) for routing and fastening cables to said surfaces. These means consist of T profiles (9) fastened at the stem part (10) of the T profile to the outer surface (1) of the crane structure, the upper part (11) of the T profile on top of and transverse to the stem part of the T profile being at a distance from the surface of the crane and substantially parallel to this surface, whereby the T profile together with the surface of the crane provide cable conduits (12) for the cables, which are open from the sides.

Abstract: An adjust and lock mechanism includes a drive gear (16) rotatably mounted on a frame and adapted to engage a drive track (15) on a member (13) to allow adjustment between the frame (1) and the member by rotation of the drive gear, the drive gear being mounted on a drive spindle (17) that can move axially relative to the drive gear and which is normally spring loaded (34) into locking engagement with the frame and can be moved axially to disengage the locking engagement and allow the spindle to be rotated to operate the drive gear. A locking engagement is provided by a dog gear at one end of the spindle. A lock release button (32) and hand wheel (18) to rotate the drive gear are located adjacent one another for joint operation. A gear train connects the hand wheel to the drive gear.

Abstract: An apparatus capable of supporting a portion of the weight of a load being transferred by a lifting device in the event of a complete failure of one of the hoisting ropes is disclosed. The apparatus includes a support structure attached atop a beam of the lifting device, and a support bar pivotally attached to the support structure. The support structure includes a stop portion that is in contact with the beam and has an upper surface opposed to an undersurface of the support bar. A hoist system is also disclosed.

Abstract: Mobile or stationary working apparatus, in particular a working vehicle, with at least one telescopic extension arm (3) which has two or more extension arm elements (31, 32, 33) which can be moved in relation to one another, with detection means being provided on the extension arm elements (31, 32, 33) and also on a base station, in particular a rotatable trailer of the working vehicle, for detecting the position of the extension arm elements (31, 32, 33) in relation to one another and with respect to the base station, with provision being made, according to the invention, for the detection means to be in the form of radio detection means, with a radio base unit (8) being arranged on the base station and further transponder units (10, 12) being arranged on the extension arm elements (32, 33).

Abstract: A support system for use on mast climbing scaffolding systems comprising a plate system with integral fastening components that attach along outer edges of a horizontal surface of the scaffolding assembly is herein disclosed. The system is utilized to mount a hoisting device to lift building tools, supplies and materials. The system may be folded thereinto a compact configuration for transport between job sites.

Abstract: The invention concerns a lattice boom crane, which is composed of at least two individual lattice boom cranes (1, 11), which each comprise a luffing lattice boom (4, 14), whose luffing angle is adjustable by a luffing mechanism (5, 15). The lattice booms (4, 14) of the individual lattice boom cranes (1, 11) are connected with each other and oriented in parallel and adjacent to each other and the luffing mechanisms (5, 15) of the lattice boom cranes (1, 11) are synchronously operated, such that the rigidly-connected lattice booms (4, 14) are synchronously luffable.

Abstract: An apparatus is provided for tarping a cargo loaded on a flat bed vehicle which includes a pair of ruggedly constructed double scissors linkages carried by an overhead horizontal traveling trolley and connectable at their lower ends to the tarpaulin. A vertically adjustable horizontal roller is provided, over which the tarpaulin is pulled during its installation in covering relation to the loaded cargo.

Abstract: In one example, a radiation scanning system and method rotates a cargo conveyance after removal from a ship for proper orientation with respect to a scanning source and detector, for scanning. A movable carriage may be provided on a crane system, to rotate the cargo conveyance. A rotating flywheel on the carriage rotates in a direction opposite the direction of rotation of the cargo conveyance, to counterbalance angular momentum generated by the rotating conveyance, to avoid or minimize twisting of the carriage. Feedback is provided to control the rotation of the flywheel. Once the cargo conveyance is in the predetermined position, the conveyance is moved between the radiation source and detector for scanning by a vertically extending radiation beam.

Abstract: The present invention relates to a rope winding system (1) for winding and unwinding a steel rope (4) of a crane (7). A rope winding system (1) according to the present invention has a rope drum (6), onto which the steel rope (4) can be wound in a plurality of layers, and a magnetic system (7) which is configured to generate a magnetic field over a section of the steel rope (4) with its magnetic flux being deflected by a movement of the steel rope (4) in such a way that the steel rope (4) is braked. A crane (7) is also discloses which is equipped with such a rope winding system (1) for winding and unwinding a steel rope (4).

Abstract: In a crawler crane of the present invention, a plurality of winches 11-14 for winding wire ropes are disposed on a rotating frame 6 of an upper rotating body 3 in a row in a plane view. A cabin 17 and a power unit 18 are disposed on the front and rear portions of either a right side or a left side of the rotating frame 6 of the upper rotating body 3. A working oil tank 36 of the power unit 18 is disposed between the cabin 17 and a driving section 31-34 of the power unit and in close proximity to a rear surface of the cabin 17. The working oil tank 36 is formed in a size which covers the substantially whole area of the rear surface of the cabin 17. In the crawler crane of the present invention, it is possible to take an anti-sound measure for the cabin to a satisfactory extent without causing cost increase. In the crawler crane of the present invention, moreover, it is possible to improve the transportability because the width of the upper rotating body can be shortened.

Abstract: A slewing crane is assembled and installed at the end of a shipping and stowage container having block-shaped corner fittings. Left and right rotatable mounts engage top corner fittings on the container, and a cross piece section engages the rotatable mounts. A boom section has upper and lower hinges rotatably mounting it on the cross piece section via the hinges' axially aligned pins to extend outwardly from the cross piece section. A hoist on the boom section lifts and moves loads, and first and second displacement mechanisms connected to the boom section linearly displace the hoist and angularly displace the hoist and boom section in a slewing motion around the axis of the axially aligned pins. An element connected between the cross piece section and a corner fitting is tensioned by a turnbuckle to securely engage both rotatable mounts and hold the slewing crane on the container.

Abstract: A friction management system for a traveling crane applies a liquid or solid friction modifier (FM) in precisely controlled quantities to the crane wheels or rail to improve performance and safety during movement of the crane. The friction modifier is applied by a nozzle mounted on a crane truck, which nozzle is opened and closed by a valve. The duration of the valve opening per second, which controls the friction modifier application rate, is approximately proportional to the average current draw, which is detected by current sensors connected to the truck motors.

Abstract: A method for handling a wind powerplant's rotor hub (11) or to handle a wind powerplant's rotor (10) using a hoist, in particular for erecting a wind powerplant or for assembling or disassembling a rotor (11) to and from such a powerplant, in particular a hub (11) or a rotor (10) being configured by means of one assembly side to the wind powerplant's tower, the hub (11) or rotor (10) being raised or held by the hoist. In the raised state, the hub (11) is tilted by a tilting mechanism (15) acting on it out of the initial, raised position by a predetermined angle of tilting, or the rotor (10) is tilted by a tilting mechanism (15) acting on the rotor blade roots of the rotor (10) through a predetermined angle of tilting. A mechanism (15) to handle a wind powerplant's rotor hub (11) of a wind powerplant's rotor (10), in particular for assembling or dismantling a rotor to or from its wind powerplant.

Abstract: The invention concerns a wind safety device for at least two outdoor cranes (2a, 2b), able to move by traveling gears (6) on a jointly shared crane track (1), especially track-mounted full gantry cranes, with holding devices engaging at or in the region of the crane track (1) to prevent the cranes (2a, 2b) from lifting up and being pulled away when certain wind speeds are exceeded, and it being possible to join together at least two neighboring cranes (2a, 2b) in the region of the traveling gears (6). In order to achieve greater safety against the lifting up and pulling away of cranes (2a, 2b) taken out of operation due to high wind speeds prevailing, it is proposed that impact elements (10a, 10b) be arranged above the coupling on the at least two neighboring cranes (2a, 2b), lying against each other when the at least two neighboring cranes (2a, 2b) are coupled together.

Abstract: A crane with a boom, on which running tracks for cable carriers are disposed, having two running tracks for the cable carriers, which engage into one another with a positive lock. One running track is connected with the crane or the boom, and the other running track is displaceable on the crane or the boom.

Abstract: The system and method of the present invention provide support for a holster mounting into which the vertical support of a portable hoist assembly is inserted. Disclosed is a saddle mount for the holster mounting usable on the top of a wall. Also disclosed is a floor supported base and cart assembly for the holster mounting.

Abstract: A method of converting off-shore installed pedestal crane from a mechanical to a hydraulic operation includes the steps of determining a load limit capable of being lifted by the hooks of the existing crane, ascertaining structural condition of the existing crane, determining operating performance parameters for and selecting various members of a hydraulic system, defining configuration and position of mounting members to mount each selected hydraulically operated member, removing existing mechanically operated components, rigidly securing the mounting members to the existing winch frame, affixing hydraulically operated members to respective mounting member and interconnecting them therebetween with hoses, and testing and certifying performance of the hydraulically operated system.

Abstract: A safety system for preventing crane operator injury. Two ergonomic tracks are attached on either side of the working crane. A fall transmitter is used whenever a crane operator is not on the floor. The fall transmitter has speed and travel distance governors that limit the speed and travel of certain aspects of the crane. In a further embodiment, a second fall transmitter is utilized by the second crane operator to assure that both operators are aware of and agree to any crane movement prior to commencing such movement.

Abstract: A hoist assembly for use in a clean room includes a hoist body which is received in a hoist cover cavity of a hoist cover. A rigging is coupled to a winch of the hoist body and to an attaching member attachable to a load. The rigging is received in a rigging cavity of a rigging cover and the rigging cover is extendable in response to an extension of the rigging from the hoist body and retractable in response to a retraction of the rigging.

Abstract: A lifting apparatus includes a plurality of preferably four carriages, each carriage supporting a lifting boom. Two booms are pinned together to define a first pair, a second two booms being pinned together to define a second pair. Each pair of booms and connected carriages are placed on a preferably common travel path. Rigging can include a horizontal beam that extends between the first pair of booms and the second pair of booms. The beam can be attached to the pinned connection of each pair of booms with a sling. A powered motor-driven winch is used to power a cable that is wound between sheaves on the lower end portions of a pair of booms that are connected together. During use, the winches are simultaneously or nearly simultaneously operated to elevate the first pair of the booms and the second pair of booms at about the same time. The horizontal beam that spans in between booms is elevated.

Abstract: The invention relates to a covering body for masts of construction cranes, electricity lines, or the like with an outer covering which is designed to partially or totally encase a mast in the direction of extension and/or peripheral direction and which furthermore has at least one rigid inner support, with which the outer covering can be arranged to be spaced at least partially at a distance from the mast. Finally, a fastening device for fastening the inner support to the mast is provided. Such a covering body according to the invention is further developed in that the inner support, by means of the fastening device, can be connected to the mast rotatably adjustable in the peripheral direction and/or adjustable in the direction of extension and that a device for active and/or passive variation of position and/or geometry of the outer covering is provided.

Abstract: Crane apparatus is equipped with a container security scanning system for scanning containers for radioactive material, such as neutron or gamma ray emissions. The crane apparatus has a crane for unloading containers from a marine vessel and placing the containers on a deck located at the portal girder level of the crane and for transferring the containers from the deck to another location. The container security scanning system comprises one or more scanning units disposed on the deck, each scanning unit having one or more scanning platforms for supporting a container such that a bottom of the container is vertically spaced from the deck. A scanning device is movable beneath the container in a space between the underside of the scanning platforms and the deck for scanning the container to detect whether radioactive material is present. Existing cranes can be retrofitted with the container security scanning system, and newly manufactured cranes can be upgraded to include such a system.

Abstract: A mobile crane, includes an undercarriage, a superstructure rotatably mounted on the undercarriage for supporting a counterweight, a slewable boom assembly and an operator's cab. At least one electric motor propels the undercarriage in an operating direction and is supplied with electric power for driving and crane operations by a power supply unit which is connected to the at least one electric motor by a cabling and configured as a diesel-electric drive, or a battery, or a multi-system drive formed by a combination of a diesel-electric drive with a battery, or a fuel-cell system.

Abstract: Drums each having an independent drive source is installed on a trolley and each of the drums has a lifting rope which is wound around it and has an unwound end locked on a suspension piece, which will suppress any need to design the lifting rope in longer length and the drums in larger size. Sun gears, carriers and planetary gears disposed in each of the drums as well as internal teeth in each of the drums so as to be integrally rotated with the drum constitute a speed reducing mechanism for transmitting rotation of a drive source to each of the drums, will enable the entire hoist to be compact in size. Unwound length of the lifting rope from each drum is adjusted to control posture of the suspension piece and load in adequate state.

Abstract: A control system for reducing cargo pendulation. The control system calculates a correction factor and adds the correction factor for the operator input motions in addition to the motion of the platform in order to provide a reference position of the suspension point of the hoisting cable. The reference position is then provided to a tracking controller so that the crane can be forced to track the needed motions for reducing the cargo pendulation.

Abstract: A drive-through work station with power operated tarping equipment is provided to efficiently and safely apply tarpaulin covers to payloads on flatbed highway trailers. The work station may include a work platform at one or both sides of the trailer being tarped.

Abstract: An overhead traveling crane is movably mounted on a truck, which is installed in the inside of a foundry and the crane provides a movable body having a elevation mechanism. At least one bag-filter type dust collector is mounted on the movable body so as to directly vacuum and remove dusty and sooty which are generated due to transfer of a ladle by means of the overhead traveling crane.

Abstract: A spreader bar includes an elongated bar member having end portions that support a flexible lifting member that is supported below the bar. The flexible lifting member is preferably comprised of a plurality of link sections that are pinned together, load carrying links depending from the flexible member, preferably at pinned connections that join the additional links.

Abstract: While a crawler body 110 is traveling, infrared sensors 144 and an elevational difference calculator 132 incorporated in a controller 130 detects the magnitude of a step present ahead of the crawler body 110. A safety speed calculator 134 calculates a safety speed based on the magnitude of the step detected and on the position of the platform 116 relative to the crawler body 110, which position is detected by various detectors 141˜143 and by a position calculator 133. A comparator 135 compares this safety speed with the traveling speed of the crawler body 110, and if the current speed of the crawler body 110 is greater than the safety speed, then the comparator 135 outputs a warning signal. Upon receiving this signal, a restrictor 136 controls a valve controller 131 to reduce the speed of the crawler body 110 such that the crawler body 110 can travel over the step safely.

Abstract: A multiple boom lifting arrangement includes a plurality of preferably four carriages, each carriage having a boom with its lower end portion pinned to the carriage. Two of the carriages are placed on a common travel path with the upper end portion of their respective booms being pinned. This provides two spaced apart pairs of carriages and booms for lifting. A horizontal beam extends between the first pair of booms and the second pair of booms being attached to the pinned connection of each pair of booms with a sling. A powered motor-driven winch is used to power a cable that is wound between sheaves on the lower end portions of a pair of booms that are connected together. During use, the winches are simultaneously or nearly simultaneously operated to elevate the first pair of the booms and the second pair of booms at about the same time so that the horizontal beam that spans in between the pinned connections of-the first and second pairs of booms is elevated.

Abstract: The protection system for outriggers of a chassis includes a non-contact distance measuring device, associated with at least one of the outriggers and the chassis, mounted on one of the outriggers and the chassis. The non-contact distance measuring device measures the distance to the ground along a predetermined angle, and generates a warning signal based on the measured distance. A controller stops operation of the outriggers in response to the warning signal.

Abstract: An overhead support system. An array of spoked rimless wheels are located over a space and supports at least one overhead cart from which a load is supported with a tension element. The load can be moved horizontally in the space by applying a horizontal force to the load causing the cart to move over the array of spoked rimless wheels carrying the load in the horizontal direction. The spoked rimless wheels rotate permitting the tension element to pass horizontally through the array of spoked rimless wheels. In preferred embodiments the spoked rimless wheel has the general shape of a star or a daisy and is referred to as a star wheel or a daisy wheel and the cart has a circular bottom surface. In preferred embodiments casters are mounted on top of the star wheels or daisy wheels to permit easy horizontal movement of the cart over the wheels. In other preferred embodiments the daisy wheels are flat on top and casters are mounted on the circular bottom of the cart.

Abstract: A hoist is constructed for powered drive by an impact tool. The hoist includes tension means for applying a force in tension to a load. Gear means are operatively associated with the tension means for producing a tension force in the tension means. The gear means include a gear element which provides a positive hold of the produced tension force when the gear means are not being driven. Impact fitting means are connected to the gear element for enabling the gear means to be power driven by an impact tool.

Abstract: A multiple boom lifting arrangement includes a plurality of preferably four carriages, each carriage having a boom with its lower end portion pinned to the carriage. Two of the carriages are placed on a common travel path with the upper end portion of their respective booms being pinned. This provides two spaced apart pairs of carriages and booms for lifting. A horizontal beam extends between the first pair of booms and the second pair of booms being attached to the pinned connection of each pair of booms with a sling. A powered motor-driven winch is used to power a cable that is wound between sheaves on the lower end portions of a pair of booms that are connected together. During use, the winches are simultaneously or nearly simultaneously operated to elevate the first pair of the booms and the second pair of booms at about the same time so that the horizontal beam that spans in between the pinned connections of the first and second pairs of booms is elevated.

Abstract: A buoyant crane is disclosed which moves loads that are entirely out of a liquid body such as water, in response to buoyant forces acting on an expandable and contractible chamber located in the liquid body. Buoyant forces acting on the chamber are produced in relation to the volume of the chamber. The chamber is movably supported in the liquid body so that it may rise and sink in accordance with buoyant forces acting on the chamber responsive to changes in the volume of the chamber. A compressed gas source supplies compressed gas (e.g., air) to the chamber to selectively change its volume. A rope and pulley system couples the chamber to a load for moving the load, which is entirely out of the liquid body, in response to movement of the chamber within the liquid body in turn responsive to the buoyant forces acting on the chamber.

Abstract: A tubular warning sleeve for surrounding a pendant cord above a control station of an apparatus having a pendant control, the warning sleeve comprising a sheet of flexible material having opposite ends, the sheet including an outer surface having thereon warning information, the sheet being rolled up so that the ends overlap, and the ends being secured together by fasteners to form the sleeve, each of the ends of the sheet being provided with apertures for the fasteners, one of the ends of the sheet being provided with at least two sets of apertures for the fasteners such that the diameter of the sleeve is adjustable.

Abstract: A pipelayer machine including a tractor with rubber mounted tracks and a boom supported by the tractor for lifting and lowering the pipe to be laid. The boom is pivoted on one side of the tractor, and the boom line winch is supported on the other side. The boom line crosses in front of the windshield of the tractor and there are specially designed boom line cable fairleads at each front corner of the cab to prevent damage to the windshield and to the driver within the cab.

Abstract: A rotating stick comprises a shaft, a prime mover, an outer casing and first and second bearings. The prime mover is aligned with the central axis of the shaft. The outer casing encloses the prime mover and at least partially encloses the shaft. The first and second bearings include first and second annular bodies mounted inside the outer casing. These two bodies cooperate to support the shaft in the outer casing for relative rotation. The second bearing includes a transverse surface which transfers a portion of the periodic forces propagating along the shaft to the outer casing. These forces are dissipated by the outer casing so that the energy propagated to the prime mover is minimized.

Abstract: After a heavy load hoisted up by a hoisting member is downed on the predetermined place, the hoisting member can be automatically dismounted from the heavy load by using the dismounting device. The hoisting member consists of a upper hoisting member and a lower hoisting member. The upper hoisting member is arranged between a base of the dismounting device and a hook of a crane. The lower hoisting member has a foundation and secured to the base, a mid portion engaged with a hoisting member engagement portion of the heavy load, and a front end fitted or inserted onto a mast erected on the base. In operation, a slider up-and-down slidably mounted on the mast is pushed up by a resilient body, in its no load condition, to a level where its top end reaches at least a top end of the mast. The slider is adapted to conquer resilient force of the resilient body while the slider hoists the base.

Abstract: A boom point construction connects the for and aft mountings of a sheave swivel to the major structural elements of a boom. The boom point includes a framework of elongated members joined together to form a truss. The framework includes assemblies of at least three members joined together at one common point and extending in different directions from the point to define three different planes. Two of the assemblies extend from opposite sides of the front swivel support and another of the assemblies extends from the rear swivel support. A member of the assemblies from the front swivel support is connected to members of the assembly extending from the rear swivel support. The boom point is shown connecting the swivel to a boom having either three or four major longitudinal structural elements.