An operator cabin may include a frame; a seat assembly supported by the frame; and one or more operator controls to control one or more components of a pipelayer machine, the operator controls being supported by the frame. The frame includes a front surface; a rear surface opposite the front surface; a first lateral surface; and a second lateral surface opposite the first lateral surface. The front surface may comprise a first front support structure and a second front support structure opposite the first front support structure. The rear surface may comprise a first rear support structure and a second rear support structure opposite the first rear support structure. A first distance between the first rear support structure and the second rear support structure may exceed a second distance between the first front support structure and the second front support structure.

A mobile crane is configured so that a boom is raised by a derrick cylinder in response to a raise signal output from a derrick lever and the derrick cylinder is stopped in response to the derrick angle of the boom reaching the maximum angle corresponding to the hoisted-down length of a rope.

An offshore platform lifting device for lifting operations at sea after sailed to a certain position of a sea surface includes an upper deck, a plurality of upright columns, a rail seat, a base disposed on the rail seat, two davit arms, two first winches, and two second winches. The upper deck has a lower pontoon. The upright columns are connected between to the upper deck and the lower pontoon. Each upright column is provided with a support leg that is longitudinally inserted through the upright column, thereby positioning the offshore platform lifting device on the seabed through the upright columns. The two davit arms are disposed the base and drives the base to move laterally through a pushing device. The two second winches each have a second cable passing through the two davit arms. A hook is disposed at a distal end of the second cable.

An offshore platform lifting device for lifting operations at sea after sailed to a certain position of a sea surface includes an upper deck, a plurality of upright columns, a rail seat, a base disposed on the rail seat, two davit arms, two first winches, and two second winches. The upper deck has a lower pontoon. The upright columns are connected between to the upper deck and the lower pontoon. Each upright column is provided with a support leg that is longitudinally inserted through the upright column, thereby positioning the offshore platform lifting device on the seabed through the upright columns. The two davit arms are disposed the base and drives the base to move laterally through a pushing device. The two second winches each have a second cable passing through the two davit arms. A hook is disposed at a distal end of the second cable.

A working machine includes a lower body, a turning body, a turning manipulating member which turns the turning body, a hydraulic motor which rotationally drives the turning body, a brake device which brakes the hydraulic motor, amain hydraulic source which supplies hydraulic oil to the hydraulic motor, and a direction control valve which controls a flow direction of the hydraulic oil according to the manipulated variable of the turning manipulating member, in which in a state where the hydraulic motor is braked by the brake device based on a manipulation of a brake manipulating member, when the turning manipulation is performed by the turning manipulating member, a brake applied to the hydraulic motor by the brake device is released with respect to turning in an indication direction indicated by the turning manipulation such that the turning body turns in the indication direction.

A crane having a luffing jib and a lifting cylinder includes a cylinder body and a movable rod hinged on the jib to raise and lower the jib, and a locking device adapted to cooperate with the lifting cylinder to mechanically lock the rod in a deployed holding position and block the jib in a raised holding configuration, and further including a spacer hinged on the jib and supporting an abutment, the spacer configured for pivoting between a release position wherein the spacer is offset, authorizing the movable rod to be displaced freely, and a locking position wherein the spacer is folded so that the abutment is able to bear on the cylinder body to fixedly maintain the movable rod in the deployed holding position.

A crane includes a luffing jib and a lifting cylinder having a cylinder body and a movable rod hinged on the jib to displace the jib in lifting motion and in lowering motion, and a locking device adapted to cooperate with the lifting cylinder to mechanically lock the rod in a deployed holding position and block the jib in a raised holding configuration. The crane further includes a spacer hinged on the jib and supporting a stop, the spacer pivotable between a release position in which the spacer is shifted, allowing the movable rod to be freely displaced, and a locking position in which the spacer is folded so that the stop is capable of abutting on a bearing surface in a ball jointed connection with the cylinder body, to fixedly hold the movable rod in the deployed holding position.

A lifting unit includes a jib foot forming a proximal part of a jib in a service configuration, a counter jib supporting a balancing ballast, a securing part between the jib foot and the counter jib to secure the lifting unit to a mast, and a cylinder connected to the jib foot such that the jib foot is movable between a lowered position and a lifted position. A second cylinder is connected to the securing part.

A mobile crane having a main jib that is mounted thereupon for luffing and that can be oriented by means of a luffing cylinder, and a main jib extension that is detachably connected to a main jib head of the main jib by means of upper and lower bolts, it being possible to angle the main jib extension about a luffing axis relative to the main jib proceeding from a base position following release of the upper or lower bolts and using an angle drive, the angle drive engaging with a foot of the main jib extension, a maximum angling angle being delimited by an adjustable angling plate, and the angling plate engaging with the foot of the main jib extension and the main jib head. The angle drive may be a component of an angling plate in the form of a combi-angling plate.

A mobile crane having a main jib that is mounted thereupon for luffing and that can be oriented by means of a luffing cylinder, and a main jib extension which is detachably connected to a main jib head of the main jib by upper and lower bolts, it being possible to angle the main jib extension about a luffing axis relative to the main jib proceeding from a base position following release of the upper or lower bolts and using an angle drive, the angle drive engaging with a foot of the main jib extension, a maximum angling angle being delimited by an adjustable angling plate, and the angling plate engaging with the foot of the main jib extension and the main jib head. The angle drive is a component of an angling plate in the form of a combi-angling plate.