Provided is a crane which can suppress deformation and vibration of a crane structure in travel and stop of the crane. Inverters are installed respectively in travel devices which are arranged on the opposite sides with a gap in a transverse direction. Each of the inverters independently measures a torque generated in a motors to which the inverter is connected and reduces the rotation speed in the command from a controller to the motor such that the greater the measured torque is, the greater a ratio of reduction is.

Provided is a crane which can suppress deformation and vibration of a crane structure in travel and stop of the crane. Inverters are installed respectively in travel devices which are arranged on the opposite sides with a gap in a transverse direction. Each of the inverters independently measures a torque generated in a motors to which the inverter is connected and reduces the rotation speed in the command from a controller to the motor such that the greater the measured torque is, the greater a ratio of reduction is.

A self-locking anti-slip rail braking device is provided. The rail braking device includes a ladder-shaped support, a lifting unit, a roller-and-wedge plate mechanism, a roller support, and a rail clamping unit. The ladder-shaped support is connected under a surface of a balance beam of a port facility, and is connected at a middle part thereof with the lifting unit. A lower end of the lifting unit is hinged to two sides of the roller support. The roller support is provided on an upper end surface thereof with the roller-and-wedge plate mechanism, and is provided at a middle part thereof with the rail clamping unit. An upper end of the rail clamping unit serves as a force application end and is configured to match the roller-and-wedge plate mechanism, and a lower end of the rail clamping unit serves as a rail clamping end corresponding to two lateral sides of a rail.

A fall arrest anchor trolley for arresting the fall of a user. In one embodiment, the invention can be a system for arresting movement of a worker after falling from an elevated work surface comprising: a rail; a trolley in rollable contact with the rail, the trolley having a body, a brake sub-system, and a plurality of wheels, the brake sub-system comprising a brake rod, a brake pad connected to the brake rod, a lanyard connector connected to the brake rod, and a resilient element; the brake rod slidably coupled to the body so that the brake sub-system is alterable between: (1) a free state in which the brake pad is spaced a distance above the rail; and (2) an arrest state in which at least a portion of the brake pad frictionally engages the rail; the resilient element biasing the brake sub-system into the free state.

A retracting rail clamp for braking or anchoring a rail-mounted machine such as a crane by clamping opposite sides of a longitudinal rail member, the retracting rail clamp comprising: a load transfer frame rigidly secured to the crane, such as by bolting; and a clamp mechanism suspended within the load transfer frame by at least one lateral pair of pivotally mounted lift levers, and operable through a first and second stage of motion between a raised, brake release position, in which the entirety of the rail clamp is disposed substantially vertically clear of the rail, and a lowered, brake set position wherein at least one opposed facing pair of main levers of the clamp mechanism engage the side surfaces of the rail.

A retracting rail clamp for braking or anchoring a rail-mounted machine such as a crane by clamping opposite sides of a longitudinal rail member, the retracting rail clamp comprising: a load transfer frame rigidly secured to the crane, such as by bolting; and a clamp mechanism suspended within the load transfer frame by at least one lateral pair of pivotally mounted lift levers, and operable through a first and second stage of motion between a raised, brake release position, in which the entirety of the rail clamp is disposed substantially vertically clear of the rail, and a lowered, brake set position wherein at least one opposed facing pair of main levers of the clamp mechanism engage the side surfaces of the rail.

A drilling rig transfer system includes a mobile transfer beam, a trolley assembly operatively attached to and moveable along the mobile transfer beam, and a connection mechanism suspended from the trolley assembly for connecting to and lifting a device. The mobile transfer beam is suspended from first and second traveling blocks through connections at first and second suspension positions along the mobile transfer beam. A method of transferring a device may include suspending a connection mechanism from the trolley assembly over a first location, lowering and attaching the connection mechanism to a device disposed at the first location, lifting the device with the connection mechanism, moving the trolley assembly along the mobile transfer beam to position the connection mechanism and the device over a second location, and lowering the connection mechanism and the device into the second location.

A drilling rig transfer system includes a mobile transfer beam, a trolley assembly operatively attached to and moveable along the mobile transfer beam, and a connection mechanism suspended from the trolley assembly for connecting to and lifting a device. The mobile transfer beam is suspended from first and second traveling blocks through connections at first and second suspension positions along the mobile transfer beam. A method of transferring a device may include suspending a connection mechanism from the trolley assembly over a first location, lowering and attaching the connection mechanism to a device disposed at the first location, lifting the device with the connection mechanism, moving the trolley assembly along the mobile transfer beam to position the connection mechanism and the device over a second location, and lowering the connection mechanism and the device into the second location.

Disclosed is trolley brake and an assembly including a trolley brake. In some embodiments, the assembly may include a channel member, and a trolley body having a first portion positioned within an interior of the channel member and a second portion extending from the channel member. The assembly may further include a locking device coupled to the trolley body, the locking device including a main body coupled to the second portion of the trolley body, a bar extending through the main body, wherein the bar is rotatable about a central axis, and a stopper coupled to a first end of the bar, wherein the stopper comprises a magnetic material. In a first position of the bar and the stopper, the stopper is in direct physical contact with the channel member, and in a second position of the bar and the stopper, a gap is present between the stopper and the channel member.

Disclosed is trolley brake and an assembly including a trolley brake. In some embodiments, the assembly may include a channel member, and a trolley body having a first portion positioned within an interior of the channel member and a second portion extending from the channel member. The assembly may further include a locking device coupled to the trolley body, the locking device including a main body coupled to the second portion of the trolley body, a bar extending through the main body, wherein the bar is rotatable about a central axis, and a stopper coupled to a first end of the bar, wherein the stopper comprises a magnetic material. In a first position of the bar and the stopper, the stopper is in direct physical contact with the channel member, and in a second position of the bar and the stopper, a gap is present between the stopper and the channel member.