A method and apparatus for lifting loads support from a crane to eliminate swaying of the load includes providing the crane with a laser source on either side of the crane. The center of gravity of the load is marked on the load and the boom is positioned such that the laser lights projection on the ground or on surface of the load and the center of gravity of the load are aligned in a straight line.

A system and method are disclosed for building a modular electrical system for a jack up rig, the method including but not limited to identifying rig equipment on the jack up rig that will be connected to the modular electrical system; selecting electrical equipment to control the rig equipment; placing the electrical equipment in an electrical module; and electrically connecting the electrical equipment to power cables and control cables inside of the electrical module; and testing the electrical equipment inside of the electrical module.

A crawler crane includes: a seating switch that detects whether an operator is in a driver seat; a turn angle potentiometer that detects the turn position of a boom; and a controller. The controller is provided with a boom turn restriction control unit for performing a boom turn-restricting control whereby the boom is not allowed to turn within a predetermined angular range above the driver seat on the basis of the output from the turn angle potentiometer. The boom turn restriction control unit includes a restriction-canceling unit that cancels the boom turn-restricting control performed by a turn-restricting unit if a preset restriction-canceling condition is met. The boom turn restriction control unit cancels the boom turn-restricting control if the seating switch does not detect an operator. Ease of operation and work can thus be improved in a remote operation mode and the like.

A height adjustment assistance device includes an initial state determination part for determining whether a suspended cargo has been lifted from a ground at a start of lifting work, a height detection part for detecting a height of a counterweight from the ground, a storage part for storing an initial height, a calculation part for calculating a target value for correcting the height of the counterweight from the ground based on the initial height and a post-work height, a notification part for notifying an operator of information regarding the target value, and a length adjustment device for adjusting a length of a hanging member by operating in a manner to change the length of the hanging member extending from a tip of a mast to the counterweight.

The present disclosure relates to a crawler crane comprising at least one camera system, wherein the camera system is adapted to detect data relating to the relative position of the crawler crane to a suspended ballast and/or to at least one travelable ballast wagon.

The present disclosure relates to a crawler crane comprising at least one camera system, wherein the camera system is adapted to detect data relating to the relative position of the crawler crane to a suspended ballast and/or to at least one travelable ballast wagon.

There is provided a crane for enabling easily carrying out an operation of a boom such as raising and lowering, telescoping, or turning, by displaying a range wherein a hook may be moved or may not be moved in a direction approaching a vehicle part of the crane. The crane includes: a vehicle; a boom positioned upon the vehicle; a wire rope being suspended from a base end side of the boom toward a leading end side thereof; a hook being hung from the leading end side of the boom and raised and lowered by winding and unwinding the wire rope; a camera for photographing an image including the hook; a display device for displaying the image; and a control device connected to the camera and the display device, the control device being for processing information. On the basis of the length of the boom or the height of the hook, the control device computes an inner boundary which is a boundary between a range where the hook may move, and a range where the hook may not move, in a direction approaching the vehicle. The display device displays an image wherein images indicating the inner boundary are superimposed on the image photographed with the camera.

A problem to be addressed by the present invention is to provide a remote operation terminal and work vehicle comprising said remote operation terminal for enabling easy and straightforward carrying out of a remote operation of a work device. Provided is a remote operation terminal (32) of a crane device (6), said terminal comprising: a terminal-side control device (42) being a control part for controlling an operation of the remote operation terminal (32) and configured to enable communication with a control device (31) of the crane device (6); a load movement operation instrument (35) being a first operation part for remotely operating the crane device (6); and a reference change operation instrument (34) being a second operation part for setting a reference of an operation direction of the crane device (6) operated by the load movement operation instrument (35). The terminal-side control device (42): computes the operation direction of the crane device (6) with regard to the operation of the load movement operation instrument (35) on the basis of the setting value of the reference change operation instrument (34), and transmits said direction to the control device (31); and prevents a change of the setting value while the load movement operation instrument (35) is being operated.

There is provided a crane including: a telescopic boom having an inner boom element and an outer boom element; a telescoping actuator that displaces the inner boom element or the outer boom element in the telescoping direction; a first coupling member that releasably couples the telescoping actuator to one of the boom elements; a second coupling member that releasably couples the pair of boom elements to each other; an electric drive source provided at the telescoping actuator; a first coupling mechanism that displaces the first coupling member or the second coupling member on the basis of motive power of the electric drive source, thereby switching a coupled state and a non-coupled state of the members that are releasably coupled by one of the coupling members; and a position information detection device that detects information relating to the position of one of the coupling members on the basis of output from the electric drive source.

There is provided a crane including: a telescopic boom having an inner boom element and an outer boom element; a telescoping actuator that displaces the inner boom element or the outer boom element in the telescoping direction; a first coupling member that releasably couples the telescoping actuator to one of the boom elements; a second coupling member that releasably couples the pair of boom elements to each other; an electric drive source provided at the telescoping actuator; a first coupling mechanism that displaces the first coupling member or the second coupling member on the basis of motive power of the electric drive source, thereby switching a coupled state and a non-coupled state of the members that are releasably coupled by one of the coupling members; and a position information detection device that detects information relating to the position of one of the coupling members on the basis of output from the electric drive source.