Abstract: A lifting system utilizing a lifting apparatus for lifting a floor (e.g., a concrete slab) using the lifting apparatus to support a floor from under the floor during lifting. The lifting apparatus may have a first portion (e.g., an extension member and saddle) installed under a slab. Piers are driven into the ground through the first portion of the lifting apparatus. Thereafter, a second portion of the lifting apparatus is operatively coupled to the to the first portion and the uppermost pier. A lifting device (e.g., hydraulic ram) is operatively coupled to the lifting apparatus and/or the pier and is used to lift the slab.

Abstract: A clamp contains: a body, an actuation rod, and a slow descending device. The body includes a first support sheet, and the actuation rod includes a second support sheet. The body further includes a drive grip, a driven mechanism, and a limitation mechanism. The limitation mechanism has a first spring, multiple first fixing protrusions, and a release lever. The slow descending device includes a second spring, multiple second fixing protrusions, a guide element, and a micro-adjustment handle. The micro-adjustment handle has a pull lever and the second spring 31 surrounds around the actuation ro. The multiple second fixing protrusions accommodate the actuation rod and are pushed by the second spring. The micro-adjustment handle has a third spring and a control lever pushed by the third spring and contacting with the multiple second fixing protrusions.

Abstract: A formwork system, including a plurality of side formwork elements configured to confront a concrete structure, a horizontal formwork panel configured to support the concrete structure, and at least one working platform, wherein the system is configured to be split in a longitudinal direction and stricken or cycled from the concrete structure in two discrete parts.

Abstract: A device for levelling an offshore foundation construction including a cylinder equipped with a fastening member for removably fastening the cylinder to a part of the offshore foundation construction, a rod mobile in axial translation with respect to the cylinder, the rod including a pushing end so configured to push against a mudmat.

Abstract: A lifting system utilizing a lifting apparatus for lifting a floor (e.g., a concrete slab) using the lifting apparatus to support a floor from under the floor during lifting. The lifting apparatus may have a first portion (e.g., an extension member and saddle) installed under a slab. Piers are driven into the ground through the first portion of the lifting apparatus. Thereafter, a second portion of the lifting apparatus is operatively coupled to the to the first portion and the uppermost pier. A lifting device (e.g., hydraulic ram) is operatively coupled to the lifting apparatus and/or the pier and is used to lift the slab.

Abstract: A system for laterally supporting a vertical shoring post is provided. The system includes a head and a jaw assembly, the jaw assembly movably mounted to the head, the head configured for selective engagement with a shoring post, and the jaw assembly configured for engagement with a beam that provides lateral support to the shoring post. The head comprises first and second arms that extend in the same general direction and when engaging the shoring post the first and second arms are disposed upon opposite sides of the shoring post. The jaw assembly includes a fixed jaw and a movable jaw, the moving member pivotably connected to the fixed jaw, wherein the fixed jaw and movable jaws are configured to receive an end of the beam therebetween.

Abstract: A floor plate assembly system for a top-down construction process includes an assembly pad formed around a vertical support core of the building. The assembly pad includes a top surface disposed at a ground level elevation of the building, and covers a footprint of the building. A plurality of tie-downs are attached to the assembly pad. A plurality of jack pedestals is positioned on the assembly pad, and are operable to support the floor plate, and raise and lower the floor plate relative to the assembly pad. Camber may be introduced into selective frame members by restraining the frame member to the tie-downs and extending a respective jack pedestal. The floor plates may be raised in their entirety to a work height with the jack pedestals to allow workers easy access to an underside of the plate.

Abstract: The invention provides a linear winch assembly (10), gripper assembly (14, 16) and a method of use. The linear winch assembly comprises a first gripper assembly comprising a first gripper block (28b) operable to grip a cable and a second gripper assembly comprising a second gripper block operable to grip a cable (17). The winch assembly comprises a first mechanism (30, 31, 32) operable to move at least part of the first gripper block out of the pathway of a cable connector to allow the connector (19) to pass through the first gripper assembly. The winch assembly also comprises a second mechanism operable to move at least part of the second gripper block out of the pathway of a cable connector to allow the connector to pass through the second gripper assembly. It also comprises a pivotable lid (28a).

Abstract: The invention relates to a method for constructing buildings having a reticular structure and to a building constructed using said method. The method comprises the steps of: erecting a set of columns (1, 2, 3, 4) that form the vertical supporting structure, on foundations or piles; arranging, in a lower zone of the structure (100), a heap (5) with fully constructed floor modules (6) inside the space defined by the columns (1, 2, 3, 4) and in the same vertical order as the definitive order planned for each of the floor modules of the structure (100) forming the building; raising the floor modules (6) by means of elevators, to place same in their definitive positions at corresponding heights; and joining the floor modules (6) to the columns (1, 2, 3, 4) by means of screwing, welding, riveting or an equivalent system.

Abstract: The present invention relates to an apparatus for engaging a first body with a second body, for example, for locking an oil rig platform to a rig leg. The apparatus comprises a driving portion, for example in the form of a driving wedge, which is moveably attachable to the first body, and an engaging portion, for example in the form of an engaging wedge, which is moveably attached to the driving portion. The driving portion is adapted to move in a first direction with respect to the second body and the engaging portion defines an engaging profile adapted to engage a complementary profile on the second body. Movement of the driving portion results in movement of the engaging portion. The apparatus also comprises an adjustment device connecting the driving portion to the engaging portion and adapted to move the engaging portion independently of the driving portion.

Abstract: A vehicle mounted T-post remover. The vehicle mounted T-post remover comprises a housing having at least one sidewall, an upper end, and an open lower end. At least one sidewall includes an interior surface and an exterior surface. A ratcheting latch system having a release lever is disposed on the interior surface of at least one sidewall. The ratcheting latch system can engage a protrusion of a T-post. The release lever disengages the ratcheting latch system from the protrusion. A curved member is disposed at the upper end and removably secures the vehicle mounted T-post remover to a construction vehicle.

Abstract: A jacking assembly for a rotor of a turbine includes an arc-shaped saddle which extends around and supports a lower portion of a rotor. A lifting beam extends over the rotor transversely to an axial direction of the rotor. The lifting beam is axially aligned with the arc-shaped saddle. Two connectors are disposed on respective lateral sides of the rotor, each connector extending between and being coupled to the lifting beam and the arc-shaped saddle such that the saddle is configured to lift the rotor vertically when the lifting beam is displaced vertically.

Abstract: The invention relates to a skidding system for an offshore installation or vessel, such as an offshore wind turbine installation ship, comprising at least one set of rails, and one or more carriages for supporting loads and moving the loads along the rails, e.g. from a storage position to an operating position and/or vice versa. At least one of the carriages is adaptable to different loads.

Abstract: A support structure (10) suitable for use as a support structure to an offshore platform (12), the support structure (10) comprising a main support strut (30) having a lower end and anchorable, in use, to the seabed (16) and an upper portion arranged, in use, to extend above sea level to a height substantially equal to, or greater than, that of the platform (12), the support strut (30) comprising a guide rail (62) extending upwardly from a level above the sea level (18) to the top of the support strut (30) for cooperating with a raising framework (90) slideably mountable to the guide rail (62), and further comprising drive means (98) cooperating between the raising framework (90) and the guide rail (62) for elevating the raising framework (90) relative to the support rail (62), the support structure (10) being characterized by: the support strut (30) and raising framework (90) each comprising tracks (70, 100) arranged to substantially align end-to-end when the raising framework (90) is elevated to the top of

Abstract: A clutchable pry bar includes a bar member with a fitting connector; a rack member fitted with the fitting connector of the bar member, including two slots adjacent to a closed end of the rack member, and including two through holes proximate to an opened end of the rack member; a ratchet shaft inserted to the through hole of the rack member, and including a first end portion disposed on one end thereof; at least one ratchet member fitted to the ratchet shaft, a plate member movably fixed to the slots of the rack member, a returning spring between pegs of the plate member and a central extension of the bar member; a stem member to be retained with the ratchet shaft after the stem member is inserted to a radial bore of the ratchet shaft.

Abstract: A clutchable pry bar includes a bar member with a fitting connector; a rack member fitted with the fitting connector of the bar member, including two slots adjacent to a closed end of the rack member, and including two through holes proximate to an opened end of the rack member; a ratchet shaft inserted to the through hole of the rack member, and including a first end portion disposed on one end thereof; at least one ratchet member fitted to the ratchet shaft, a plate member movably fixed to the slots of the rack member, a returning spring between pegs of the plate member and a central extension of the bar member; a stem member to be retained with the ratchet shaft after the stem member is inserted to a radial bore of the ratchet shaft.

Abstract: A caulking gun includes a gun body, a push rod, a push plate, an adjusting knob, and a piston lever. Thus, the adjusting knob is rotated to move away from the push plate to increase the incline angle of the push plate, so that the push plate is locked on the push rod in a tilt manner to lock and move the push rod without having to replace the push plate, thereby enhancing the lifetime of the caulking gun.

Abstract: A caulking gun includes a gun body, a push rod, a push plate, an adjusting seat, a driving member, and an elastic member. Thus, the adjusting seat is movable in the gun body by rotation of the driving member to adjust the incline angle of the push plate by guidance of the tapered urging face of the adjusting seat so as to increase the incline angle of the locking hole of the push plate, so that the locking hole is locked on the push rod in a tilt manner so as to lock and move the push rod, without having to replace the push plate, thereby enhancing the lifetime of the caulking gun.

Abstract: A method and apparatus involving releasing the rotor (1) and turning it to and fixing it at top dead center, attaching an extractor head to an exposed end of the hammer axle. A cross-piece (2.1) is applied and a releasable element of a slide (2.4) of a hammer axle puller is pulled, making a releasable connection between cross-piece and rotor attachment elements. The slide is moved to a position in which the puller head is connected to the slide in a shape-locking manner, securing the hammer position, returning the carriage whilst extracting the hammer axle (1.5) to release the hammer. The connection between the head and slide is released, moving the slide until the head and slide re-engage and returning the slide again to extract the hammer axle until the entire hammer and/or protective cap (1.4) and axle if appropriate are extracted. An Independent claim is also included for an arrangement for implementing the method.

Abstract: The device has two supports (15, 16) which can be moved in relation to each other in a transverse direction to the axis (2) of the traction element (1). Several clamping jaws (19, 20) are displaceably mounted in pairs opposite each other on said supports. The clamping jaws (19, 20) have surfaces which grasp the traction element (1). When strain is placed on the traction element, the clamping jaws are displaced linearly at increasing distances except for the rear pair, in such a way that the clamping force can be evenly distributed over a great length, despite the extension of the traction element (1). This allows, for example, steel cables with a high traction force to be tensioned without damaging the cable.

Abstract: A locking device installed in a cargo support to lock a retractable tube, including a holder frame fastened to the outer tube of the retractable tube, a rack moved in a longitudinal sliding way defined between two parallel lugs of the holder frame, a driving lever pivoted to the holder frame for moving the rack, and a locking block pivoted to the holder frame and retained by a spring to lock the driving lever, wherein a L-shaped locating plate is mounted in the holder frame for the positioning of the outer tube of the retractable tube, having a round hole on a transverse section thereof through which the inner tube is inserted into the outer tube, two stop flanges bilaterally extended from a longitudinal section thereof and respectively engaged with respective end notches on the holder frame, and a lug extended from one stop flange and fastened to a lug at the holder frame; the holder frame and the locking block are respectively made of iron.

Abstract: An apparatus for moving a movable assembly along a mast is provided. The movable assembly has a bore adapted to receive the mast passing through it. The movable assembly has a release and retain mechanism; a uni-directional drive mechanism; and a switching mechanism for engaging the uni-directional drive mechanism. The switching mechanism has a shaft positioned within the movable assembly, generally oriented parallel to the bore, that is capable of rotational movement around the longitudinal axis of the shaft and axial movement along the longitudinal axis of the shaft. The switching mechanism also has a drive pin attached to the shaft of the switching mechanism that is oriented generally perpendicular to the longitudinal axis of the shaft. The switching mechanism also has a mechanism for affecting the axial movement of the shaft that is preferably in the form of a cam. The release and retain mechanism has a biased release lever defining a slot that is sized to receive the mast.

Abstract: An uplift assembly has a first uplifter, a second uplifter, a rod enclosed by the first uplifter and the second uplifter, a first positioning plate connected to the first uplifter, a second positioning plate connected to the second uplifter, a first clamping plate clamping the first positioning plate, a second clamping plate clamping the first positioning plate, a third clamping plate clamping the second positioning plate, a fourth clamping plate clamping the second positioning plate, a first cylinder disposed between the first clamping plate and the third clamping plate, a second cylinder disposed between the second clamping plate and the fourth clamping plate, and a base plate disposed beneath the third clamping plate, the fourth clamping plate and the second uplifter.

Abstract: A locking mechanism is disclosed for use on the legs of a jack-up offshore platform. Each chord of the legs includes a rack for cooperation with pinions used in raising and lowering the legs. The locking mechanism of the invention includes a rigid frame attached to the hull of the platform and housing a plurality of vertically aligned toothed chock segments adapted to engage the teeth of the rack on a leg. The chock segments have upper and lower inclined surfaces which cooperate with upper and lower movable wedges for supporting the chock segments. The design makes the chock segments sufficiently adjustable for independent alignment and engagement of the teeth of each chock segment with the corresponding teeth of the rack. Dimensional variances in the rack teeth spacing, resulting from manufacturing tolerances, thereby are accommodated and force concentrations between the rack teeth and chock teeth are minimized.

Abstract: A system is provided for relieving the downwardly acting load on a structural column, such as a reinforced concrete column supporting a roadway, bridge, overpass, or other massive structure. Horizontally oriented keyways are formed into the concrete column on transversely opposite sides thereof and at the same elevation thereon. The keyways are of rectangular cross section. Clamps likewise having vertical bearing surfaces and keys that extend horizontally with a corresponding rectangular cross section are clamped against the transversely opposite sides of the columns so that keys project into the keyways. A load bearing support system is positioned beneath the clamps. The bolts are torqued to tighten the clamps and hydraulic jacks are inserted in between the lowermost clamps and the load-bearing support structure to exert vertically upwardly acting forces against the clamps. These vertical forces counter the load on the column, thereby preloading the column.

Abstract: A lifting and supporting apparatus having a vertically oriented robe interconnected to a smaller, vertically oriented rod by a lifting device. A large bracket or the like is secured to the robe so as to provide a surface upon which an object can rest. The lifting device provides a means by which to move the rod downwardly with respect to the tube, thus allowing both the tube and the object to be easily raised and supported above the ground upon which the rod rests.

Abstract: An apparatus is provided for lifting modular furniture. The apparatus comprises a central shaft and housing slidably mounted on the shaft. Either the housing or the shaft is supported by a base support and the other of the housing and shaft is moveable. The apparatus further comprises a jig which is adapted to mate with the furniture to be lifted, and means for raising and lowering the jig to thereby raise and lower the furniture. The apparatus further includes a lateral stabilizer which stabilizes the furniture once it is raised off the floor.

Abstract: An adjustable bed includes a base frame, a mattress frame and linkage for mounting the mattress frame for relative movement with respect to the base frame. A mechanical jack is operatively connected to the base frame and the linkage for moving the mattress frame between high and low positions. A mechanical jack includes an enclosure. A bearing supports a ram within the enclosure for extension and retraction. A drive plate and a hold plate define apertures through which the ram extends. A drive bar is shifted by rotation of an actuator shaft to lock the drive plate to the ram and extend the ram from the housing. The drive spring resiliently biases the drive plate to an unlocked or return position. A hold spring biases the hold plate to a locked position to prevent return movement of the ram into the enclosure. A release bar is shifted into engagement with the hold plate upon reverse rotation of the actuator shaft to release the plate and permit lowering of the ram into the enclosure.

Abstract: An apparatus is provided for lifting modular furniture. The apparatus comprises a central shaft and housing slidably mounted on the shaft. Either the housing or the shaft is supported by a base support and the other of the housing and shaft is moveable. The apparatus further comprises a jig which is adapted to mate with the furniture to be lifted, and means for raising and lowering the jig to thereby raise and lower the furniture. The apparatus further includes a lateral stabilizer which stabilizes the furniture once it is raised off the floor.

Abstract: An improved pump jack of the type comprising a metal frame that has two parallel spaced frame members carrying upper and lower shackle assemblies arranged to grip a supporting pole, and a pump arm coupled to the frame and the upper shackle assembly for raising the jack. An improved releasing mechanism is provided comprising a U-shaped release member disposed between the two frame members. The U-shaped release member has two opposed struts each provided with an elongate hole adjacent one end to slidably and rotatably receive a pivot shaft that is anchored in the two frame members. The elongate holes in the opposite ends of the release member's side struts are aligned with holes in the forward ends of the side arms of the shackle member of the lower shackle assembly. The holes in the side arm of the lower shackle member are sized and shaped to non-rotatably accommodate the front clamping bar, with the latter acting to pivotally interconnect the U-shaped release member's side struts and the lower shackle.

Abstract: An improved apparatus and method for engaging beams is disclosed. A frame is positioned so that each end of the frame is adjacent to opposing surfaces of the beam. A shoe is located between one surface of the beam and the upper end of the frame, and a series of inclined plates are located between the shoe and the upper end of the frame. A hydraulic cylinder is operated to move the inclined plates, until the plates are perpendicular to the shoe, to cause the shoe and the lower end of the frame to engage the beam. Another hydraulic cylinder located between the frame and an object such as a drilling rig can be operated to move the object relative to the beam.

Abstract: A pump jack for traveling up and down a pole includes a frame member which supports a lower shackle having a front and a rear gripping rods applying a clamping force for gripping the pole. A pump arm pivotally supports and operates an upper shackle also having a front and a rear gripping rod for clamping the pole. The lower shackle has a single U-shaped yoke pivotally supported on and biased to a support arm to improve the leverage for operating the lower shackle. The upper shackle is provided with a freely rotatable roller mounted on the upper shackle so as to space the bitting front rod of the upper shackle from the pole to permit stepping up of the upper shackle. The usual tension springs on the upper shackle are eliminated to thereby permit less force needed for its operation.

Abstract: A pump jack for traveling up and down a pole includes a frame member and upper and lower shackles supported on the frame member. A pump arm is coupled to the pump jack and is operated for alternatively gripping the pole by the upper and lower shackles. The upper shackle has a helical rod which is cranked by a handle to roll along the surface of the pole. To prevent an accidental rolling of the helical rod and thus slipping of the pump jack down the pole, and anti-spin friction device including a rubber disc and a bolt acting thereon, is provided on the end of the helical rod opposite to that which carries the handle.

Abstract: Motive power device for a delivery device located at the base of an upright silo in the shape of a worm screw rotatable about its longitudinal axis, which is swivelable around a central bearing across a circular annularly shaped bottom surface of the silo with the help of a step motor, which consists of two identically designed shoe brakes self-locking counter to the drive direction and engaging at an abutment assigned to the silo wall, of which the one is linked rigidly and the other one displaceably through a controllable power cylinder in the area of a support bearing of the worm and cooperates with the abutment located at the silo wall.

Abstract: A work platform (10) is guided for up and down movement along support columns (12). Advance/retract cylinders (50, 52) are interconnected between a portion (26) of the platform (10) and a first support (28). Advance/retract cylinders (64, 66) are interconnected between the platform (10) and a second support (30). Each support is in the nature of a clamping mechanism. Each includes a pair of clamp members (32, 34) and (54, 56) which are pivotally connected together. Hydraulic cylinders (46, 48) and (60, 62) move the members (32, 34) and (54, 56) together and apart. When these members (32, 34) and (54, 46) are moved apart, they move grip pads (44, 58) into gripping contact with the support column (12). When they are moved together, they move the gripping pads (44, 58) out of contact with the support column (12). In use, one support (28, 30) is clamped to the support column (12) while the other is unclamped.

Abstract: Apparatus for skidding a drilling rig of the type having a roller mechanism which includes at least one roller for non-rotatingly supporting at least some of the rig on a platform and at least one roller for rotatingly supporting at least some of the rig while it is skidded. The drilling rig platform is supported by beams having a vertical web mounted below each non-rotating roller. The web is in vertical alignment with the vertical axis of its associated non-rotating roller. A beam having a vertical web is mounted beneath the rig above each rotating roller. The rig beam web is in vertical alignment with the vertical axis of its associated rotating roller.

Abstract: An apparatus for removing tubes from a tube sheet, wherein the tube to be removed is engaged from the side of the tube with the force for withdrawing the tube being applied against the outer peripheral surface of the tube by a tube-pulling device which, when in operative engagement with the tube to be removed, is positioned parallel to the tube and engages the outer peripheral surface thereof. A selectively actuable reciprocating hydraulic cylinder provides gripping engagement with the tube to incrementally retract the tube relative to the extracting apparatus, while continuously maintaining a positive engagement with the tube throughout the removal operation.

Abstract: A hydraulic apparatus is shown for moving a heavy load along an I-beam shaped structural member comprising a releasable clamping assembly and a double acting hydraulic jacking cylinder. The releasable clamping assembly includes a ramp plate, a pair of ramp mating members and a pair of jaw members having a cavity defined by opposed sloped walls having a bearing surface which cooperate with a ramp plate and ramp mating members causing the gripping surface of the ramp plate and ramp mating members to engage the flange of an I-beam. The releasable clamping assembly transmits a thrust load from a jacking cylinder thrust to the jaw member which reacts to apply a clamping force to the ramp plate and ramp mating members such that a thrust load away from direction of load travel will result in the ramp plate and the pair of ramp mating plates being urged towards each other to grip the flanged surface of the I-beam and arrest the motion of the jacking cylinder relative to the I-beam.

Abstract: A friction type carpenter jack has a carrier capable of movement upwardly when the inner surface of a jacking friction bar is capable of frictionally gripping the shaft. A downwardly jacking means also allows the carrier to move along the shaft toward a base plate. The downward movement is facilitated by a load holding friction bar being displaced angularly downwardly thereby having its inner surface of the shaft opening frictionally gripping the shaft. The carrier is rotatably mounted along the shaft and includes a plurality of holes for nail placement therethrough to secure a first workpiece. A head plate is also rotatable about the shaft and includes a plurality of openings for nail placement therethrough to secure a second workpiece. The jacking action of the carpenter jack permits the first workpiece to be moved toward the second workpiece for a variety of applications. The carpenter jack further includes a locking means for holding the carrier along the shaft in a stationary position.

Abstract: The vehicle has front and rear sets of wheels (24) carried on sprung arms (20). Each wheel can be locked by a clutch (26). One set of wheels is locked while a ram (32) is operated, causing the other set of wheels to roll forward. The main body (10) of the vehicle can be rotated relative to the wheels (24) by means of a motor (48) operating via a drive belt (50). The interior of the body (10) is pressurized with inert gas, suitably nitrogen exhausted from the propulsion system which is vented by a one-way valve 38.

Abstract: The technique for replacing an existing underground cable and a specific apparatus for doing so are disclosed herein. The apparatus includes a main body or cable follower which is interconnected with the cable to be replaced for slidable movement along the latter. At the same time, the apparatus provides means for reaming around the cable, preferrably by means of one or more fluid jets. Once the soil surrounding the cable has been loosened using this apparatus, the cable can be easily pulled out of the ground. At the same time, the replacement cable can be attached to the existing cable and pulled into its place.

Abstract: A two-piece, telescopic climber, which is insertable into a drillhole behind cylindrically shaped explosive charges, alternately advances one and then the other of its two telescopic pieces in the direction of the drill hole thereby to urge the charges forwardly thereof into the hole. Each piece has thereon means which expands outwardly against the wall of the drill hole to hold that piece stationary while the other piece advances. At least one of the two pieces can be removed from the drill hole to be used repeatedly.

Abstract: A jacking mechanism for jacking a well casing or other well pipe vertically, and including a hydraulic control system in which a reversible variable displacement pump acts in one condition to deliver pressure fluid in parallel with another pump to the lower end of a jacking cylinder to actuate the piston thereof upwardly, with fluid discharging from the upper end of the cylinder to the variable displacement pump and being metered therethrough to regulate the rate of upward movement of the piston. In a second condition of the apparatus, flow through the variable displacement pump is reversed to lower the piston, and a variable restriction valve regulates discharge of fluid from the lower end of the cylinder to act with the variable displacement pump in regulating downward movement of the piston and supported pipe.

Abstract: A pump jack for traveling up and down a pole. The pump jack includes a frame member supporting a lower shackle member which includes front and rear clamping bars which can apply a coupling force for gripping the pole. A pump arm is pivotally coupled to the frame member and further pivotally supports an upper shackle member having a front helical rod and a rear clamping bar for also applying a clamping force for gripping the pole. The two shackle members are suitably biased to alternately position one of the shackle members in gripping relationship with the pole. The pump arm is used to step upwardly the pump jack along the pole. A release mechanism is coupled to the lower shackle for disengaging it from the pole. An over the center spring loaded handle coupled to the helical rod is used to roll the pump jack down the pole. The handle prevents accidental downward rolling during the upward stepping of the pump jack along the pole.

Abstract: A tool (10) for the installation and removal of back pressure valves or plugs in a wellhead under pressure conditions to permit repair and replacement of wellhead outlet valves. The tool (10) comprises an elongate cylindrical housing (31, 32, 33) in which a manipulator rod (30) is slidably mounted in axial alignment therewith. The tool (10) includes a piston (55) which is sleeved about the rod (30) and adapted to be selectively clamped thereto. The manipulator rod (30) is provided at one end with a back pressure valve of plug (84) attached thereto. The tool (10) includes a fluid controls system which is connectable to an external fluid pressure source (P) or the pressure of the well itself.

Abstract: Disclosed is a rig for working on wells, and including a pair of continuous chains for moving a pair of pipe holders along a mast. Each of the two pipe holders is fixed to a point in each chain. The chains are driven along parallel paths by twin motors with linked drive shafts. The motors are mounted on the top of the mast so that only one side of the closed loop on each chain is loaded when the pipe is being pulled from a well. One of the pipe holders may comprise a snubbing head which may be operated in reciprocal motion for high speed snubbing of pipe into a well.

Abstract: A system for supporting a long, heavy dredge pipe string from a moving surface vessel, with a minimum of stress being applied to the pipe. The system comprises a gimbaled platform, supported over a central well through a vessel by two horizontal axes perpendicular to each other. A carriage is supported from the platform on hydraulic piston rods. Pipe string support plates are movably secured to facing surfaces on the carriage and platform, arranged about central openings, to permit close-coupling of the two sets of support plates when transferring the pipe string. There is also provided a pair of lateral support members for the pipe string at the bottom of the well.

Abstract: A linear hydraulic winch is provided comprising a frame to which are fixed symmetrically two hydraulic double-acting jacks, enclosing two self-clamping jaws for alternately clamping the axial cable to the end of which the load is fixed, aligned along the axis of symmetry of said winch, one of them being interlocked in translation, along said axis, with the cylinders of these jacks and the other with the pistons thereof. These self-clamping jaws are formed by wedges comprising cylinders inserted between the corresponding oblique faces of their outer and inner elements, said cylinders being truncated through two parallel planes, symmetrical with respect to their axes, and perpendicular to said oblique faces.

Abstract: A jack usable for leveling a marine platform jacket by lifting a tubular leg or pile guide relative to a pile extending upwardly therethrough includes a gripping unit having slips which engage and grip the pile and which in a predetermined elevated condition of the tubular member are engaged by that member and urged axially thereby in a grip tightening direction acting to positively lock the gripping unit against movement either upwardly or downwardly relative to the pile.

Abstract: A device for coupling together two bodies in any position with respect to each other, which bodies are mounted for a linear displacement with respect to each other, in particular in a self-raising platform structure for coupling together the platform and a leg of the structure, the device comprising at least one pair of first pawls (3), each pawl of which is connected to one of the bodies for a pivotal movement and the contact parts thereof are shaped so that upon a pivotal movement of the pawls towards each other points of the contact parts approach each other, so that the relative movement between the bodies will be inhibited in one direction while being permitted in the other direction, at least one pair of second pawls (4) having the same construction as and spaced apart from the pair of first pawls being provided, which are mounted in such a manner that upon a pivotal movement thereof towards each other corresponding points of the contact parts of the second pawls will approach each other to inhibit rela