A self-installing offshore column stabilized semi-submersible platform has at least one vertical buoyant ballastable column, a telescoping keel tank or stiffened damper plate movably connected with the vertical column that extends and retracts relative to a lower end thereof, and a tilt and telescoping wind turbine tower assembly pivotally coupled to an upper end of the vertical column telescopes and reciprocates relative thereto between a horizontal retracted position and an axially extended vertical position. A wind turbine with blades is coupled to a top portion of the upper section of the tower assembly. The relative position and weight of the keel tank or damper plate is selectively adjustable to raise or lower the center of gravity of the entire mass of the semi-submersible platform including the wind turbine and tower assembly with respect to the center of buoyancy of the platform.

A method of assembling a drilling rig may include aligning a trailer with a drilling rig support structure, the trailer carrying a mast and the drilling rig support structure including a step-down substructure. A first end of the mast may be positioned over the drilling rig support structure and arms may be extended from the mast to the drilling rig support structure so that the drilling rig support structure supports the first end of the mast. The mast may translate along a length of the drilling rig support structure. The mast may be coupled to the drilling rig support structure.

A method of building an offshore windmill includes, using a 3D-heave-compensated crane, placing on a windmill pedestal a lifting jack having a receiving region, and fixing the lifting jack to the windmill pedestal such that the lifting jack can be later removed, and such that a windmill column can be placed within the receiving region directly on the windmill pedestal. The windmill generator is installed using the 3D-heave-compensated crane. The windmill column is partially erected on the windmill pedestal using the 3D-heave-compensated crane and the lifting jack. Before the windmill is fully erected, windmill blades are placed on the windmill generator using the 3D-heave-compensated crane, and the erection of the windmill column on the windmill pedestal is completed using at least the lifting jack. Using the 3D-heave-compensated crane, the lifting jack is removed from the windmill pedestal.

An improved system and method for bracing, transporting, assembling, and disassembly of drilling equipment at oil and gas land-based well sites. The system has a substructure with side boxes support bracing that are in a scissor jack (or grand pli) style bracing with telescoping tension link(s), linking pins, and vertical hydraulic cylinders. These linking pins are set after raising the substructure and secure the telescoping tension link, support arms, and support bracing in place to maintain the integrity of the substructure. Alternatively the system has a substructure with side boxes support bracing that are in a scissor jack (or grand pli) style bracing with screw jacks and a means of stabilization during substructure raising. The substructure bracing reduces the overall length, reduces the upper and lower box spans, and balances the raising loads, subsequently lowering the transport weight of the side box such that a commercial walking system may be integrated into the side box and remain there during transport while maximizing the operating drill floor height while minimizing the transport height.

A support tower, for example for supporting telecommunications equipment thereon, is mounted on a tower base having radially projecting frame members and ballast receptacles at the outer ends of each frame member to receive ballast material to support the tower in a foundationless manner on a ground surface. A coupler is provided for supporting the support tower relative to the radial frame members of the base such that the support tower is pivotal about a horizontal axis between an assembly position along the ground and a raised position. Lifting equipment can thus be connected directly between the support tower and the tower base without the need for auxiliary lifting equipment such as a crane or boom truck, for raising of the tower on site in a low cost manner.

A support tower, for example for supporting telecommunications equipment thereon, is mounted on a tower base having radially projecting frame members and ballast receptacles at the outer ends of each frame member to receive ballast material to support the tower in a foundationless manner on a ground surface. A coupler is provided for supporting the support tower relative to the radial frame members of the base such that the support tower is pivotal about a horizontal axis between an assembly position along the ground and a raised position. Lifting equipment can thus be connected directly between the support tower and the tower base without the need for auxiliary lifting equipment such as a crane or boom truck, for raising of the tower on site in a low cost manner.

Disclosed is a tower lifting device for a rotary blasthole drill, comprising a hydraulic cylinder (5), an extending oil path (7), a retracting oil path (6), a speed control oil path (14) and a proximity switch (3), wherein the extending oil path (7) is connected to a non-rod-end chamber of the hydraulic cylinder (5), and an extension control unit is provided on the extending oil path (7); the retracting oil path (6) is connected to a rod-end chamber of the hydraulic cylinder (5), and a retraction control unit is provided on the retracting oil path (6); the speed control oil path (14) is connected to the retracting oil path (6), the speed control oil path (14) is connected to a speed control valve block (15) in series and the tail end thereof is connected to an oil tank (16); the proximity switch (3) is arranged on a tower supporting frame (2) for controlling the switching on and off of the speed control valve block (15), and when the tower (4) is approximately in a horizontal state, the speed control valve block (15) is on. By using such a tower lifting device in the present invention, the speed at which the tower is laid down to a horizontal state can be conveniently controlled.

The present invention provides a system which allows users to mount multiple pieces of equipment to a tower and it has the unique capability to adjust a steel frame to level without additional equipment. In accordance with a first preferred embodiment, the present invention includes a duel locking system that includes a taper adjusting bolt to adjustably position the frame level with the earth. Further, the dual locking system of the present invention preferably further includes the use of retaining bolts to keep the assembly positioned correctly. According to a further aspect of the present invention, once the taper adjusting bolt is in its desired position, the retaining bolts are preferably tightened to lock the frame in place, with the taper adjusting bolt acting as a redundant measure to help maintain the level state.

A tower segment of a tower of a wind turbine, a tower portion of a wind turbine, a tower of a wind turbine, a wind turbine, a method of producing a tower segment of a wind turbine and a method of connecting tower segments of a wind turbine. The tower segment includes a compression element and a tension element, wherein the tension element is arranged with its main direction of extent substantially horizontally in the installation state and is spaced from the tower segment in a direction in orthogonal relationship with its main direction of extent and is connected to the compression element by way of an intermediate element.

To ensure maintenance operations for an architectural structure using a mast climber without any limitation on the stability of a mast and locations where a mast can be erected. A side wall 101 of an architectural structure 100 is fitted with a fixing member 130 at a level higher than the ground 500. The fixing member 130 is fitted with fixture studs 132. A mast 200 is erected on the fixing member 130 with its lower end secured to the fixture studs 132. A climbing work platform 210 that travels up and down the mast 200 is fixed to the mast 200. A worker performs maintenance operations on the climbing work platform 210.