A jack, comprising: a top plate adapted to contact a load; a base plate positioned below the top plate; at least one actuator coupled perpendicularly between the base plate and the top plate; wherein the at least one actuator is operable to move the top plate between a lowered position and a raised position to thereby lower and raise the load; and, at least one locking assembly adapted to lock the top plate in the raised position.

There is disclosed a lifting apparatus and a method for lifting a shovel including its upper part, its lower part, and its boom while the shovel handle and dipper remain on the ground. The lifting system may comprise six lifting devices arranged in three pairs that are disposed under the shovel on three lines: front, middle and rear (ref. FIG. 10), the rear line being under the shovel counterweight. The lifting system is connected to a power and control unit from which, through the use of a programmable logic controller and level detectors, metered hydraulic power is selectively applied at each lifting point in order to raise the shovel to a desired height while in doing so maintaining it level with a pre-set lifting plane throughout the entire operation.

A modular boost system can be added to a jack to enable greater lift capacity of the jack. One example can involve a jack that is positionable at a well surface for moving a tubing string through a wellbore in a subterranean formation. The jack can include a frame and an adjustable plate that is alternately (i) attachable at a stationary location in the frame for fixing the adjustable plate at the stationary location or (ii) detachable from the stationary location in the frame to enable the adjustable plate to vertically move within the frame. A boost cylinder can be removably coupled to the adjustable plate and a base for selectively supplying an additional lift capability to the jack.

A vehicle lift system includes a plurality of mobile lift columns each including a wireless communication system for sending and receiving wireless signals, each of the plurality of mobile lift columns further including an inclinometer for detecting an amount of tilt of the plurality of mobile lift columns. A remote control unit includes a wireless communication system capable of transmitting wireless control signals to the plurality of mobile lift columns. A control unit is associated with the plurality of lift columns for controlling operation of the plurality of lift columns, the control unit further receiving a signal indicative of the amount of tilt of the plurality of mobile lift columns and providing a warning signal if any mobile lift column has an amount of tilt exceeding a predetermined amount.

A lifting device that includes a central portion and first and second laterally extending lifting arms. Each arm extends away from opposite sides of the central portion and includes a lifting cradle disposed on a distal portion of the associated laterally extending lifting arm. Each laterally extending lifting arm and associated lifting cradle is operable to securely engage with a gear leg of a vehicle and lift when an upward force is received by the central portion.

A jack, comprising: a top plate adapted to contact a load; a base plate positioned below the top plate; at least one actuator coupled perpendicularly between the base plate and the top plate; wherein the at least one actuator is operable to move the top plate between a lowered position and a raised position to thereby lower and raise the load; and, at least one locking assembly adapted to lock the top plate in the raised position.

There is disclosed a lifting apparatus and a method for lifting a shovel including its upper part, its lower part, and its boom while the shovel handle and dipper remain on the ground. The lifting system may comprise six lifting devices arranged in three pairs that are disposed under the shovel on three lines: front, middle and rear, the rear line being under the shovel counterweight. The lifting system is connected to a power and control unit from which, through the use of a programmable logic controller and level detectors, metered hydraulic power is selectively applied at each lifting point in order to raise the shovel to a desired height while in doing so maintaining it level with a pre-set lifting plane throughout the entire operation.

A system includes a platform having an upper surface and defining a recess having a floor, the recess configured to seat a dish, and a movable securing frame that is movably connected with the platform, the frame including a lift support having an upper surface that is movable along a path from a first location that is beneath the floor of the recess, through the recess, to a second location that is coplanar with the upper surface of the platform. A motor configured to cause oscillation of the platform and the movable securing frame can be used. A method of using the system can include placing a dish above a recess defined by an upper surface of a platform, and lowering the frame with respect to the platform, thereby seating the dish within the recess.

A hydraulic power unit for a floor jack that includes a secondary safety check valve (SSCV) to provide additional leakdown protection, backing up the main check valve. The SSCV acts as a safety measure to prevent the unit from losing load bearing capabilities if the main check valve fails. In addition, the SSCV acts as a means to prevent debris from entering the main check valve, thereby reducing the chance for failure due to an obstruction.

A grinding mill for pulverizing material includes a platform having an upper surface and defining a recess having a floor, the recess configured to seat a dish in which the material is disposed, and a movable securing frame that is movably connected with the platform, the frame including a lift support having an upper surface that is movable along a path from a first location that is beneath the floor of the recess, through the recess, to a second location that is coplanar with the upper surface of the platform. A motor configured to cause oscillation of the platform and the movable securing frame can be used. A method of using the grinding mill can include placing a dish above a recess defined by an upper surface of a platform, and lowering the frame with respect to the platform, thereby seating the dish within the recess.