Disclosed are tower erection systems and tower climbing systems and associated methods of operation. A tower erection system, in accordance with various embodiments, includes a ground-installed lifting structure, and a lifting frame configured to latch onto individual tower sections and traveling vertically inside the ground-installed lifting structure, lifted by a winch-and-cable or other lifting mechanism. Using this system, a tower may be assembled from multiple sections from the top down. A tower climbing system, in accordance with various embodiments, includes upper and lower climbers that can latch onto the lateral surface of a tower and a lifting mechanism that can move the climbers vertically relative to each other. The system can be used to carry a crane or other heavy equipment up and down along the tower. A climbing crane may be used, for example, during tower construction, or to reach the top of the tower for maintenance or repair.

A pole cradle is disclosed. The pole cradle including a first leg; a second leg; a third leg positioned between and pivotally connected to the first and second legs by a pivot connector extending through the first, second, and third legs; and wherein the third leg pivots relative to the first and second legs between a first position where the first, second, and third legs lie in plane to form a flat surface and a second position where the first, second, and third legs form a V-shaped receiving section.

A pole cradle is disclosed. The pole cradle including a first leg; a second leg; a third leg positioned between and pivotally connected to the first and second legs by a pivot connector extending through the first, second, and third legs; and wherein the third leg pivots relative to the first and second legs between a first position where the first, second, and third legs lie in plane to form a flat surface and a second position where the first, second, and third legs form a V-shaped receiving section.

A method for creating a tapered spiral welded conical structure where the overall shape of the cone is first graphically slit axially and unwrapped, and then a series of construction arcs and lines are created to form the edge lines of a strip that can then be wrapped (rolled) to form a tapered conical structure. The edges of the spirally wound strip can be welded together, and a very large conical structure can thus be achieved. Various construction options are presented from a constant width strip to strip made from straight segments. Equations are given for the formation of the strips to enable those skilled in the art of spiral welded tubing to practice the invention.

A lifting device for poles, such as a mast for a sailing ship, a Christmas tree, a pole for supporting wires or the like, are either raised to a vertical position or laid down to a horizontal position, i.e. the lifting device may be used both when a pole is brought from a horizontal to a vertical position and when a pole is brought from a vertical to a horizontal position.

A wind turbine foundation comprising a concrete support slab having a horizontal rebar grid therein, a concrete pedestal integral with the support slab and having vertical post tensioning elements therein and a plurality of concrete ribs on top of and integral with the support slab and integral with the pedestal, the ribs having rebar therein and extend outwardly from the pedestal, the pedestal, slab and ribs are connected to each other to form a monolithic foundation. The foundation design reduces the and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

Hoists, platforms and davits are described as well as methods of securing same to telecommunication and other towers. The hoists, platforms and davits may be secured to the towers on a temporary basis using clamps. The clamps may include brackets and cables. The cables may be attached to the brackets, may wrap around the outer surface/perimeter of the tower pole/leg and may use tension to keep the bracket in place.

A wind turbine foundation comprising a concrete support slab having a horizontal rebar grid therein, a concrete pedestal integral with the support slab and having vertical post tensioning elements therein and a plurality of concrete ribs on top of and integral with the support slab and integral with the pedestal, the ribs having rebar therein and extend outwardly from the pedestal, the pedestal, slab and ribs are connected to each other to form a monolithic foundation. The foundation design reduces the weight and volume of materials used, reduces cost, and improves heat dissipation conditions during construction by having a small ratio of concrete mass to surface area thus eliminating the risk of thermal cracking due to heat of hydration.

A method for installing trays in a case where a plate tower is horizontally placed or approximately horizontally placed. No manhole is formed on a cylinder body of the plate tower, so as to reduce damage to the cylinder body of the plate tower, thereby improving the airtight performance of the plate tower. Since the trays are installed in a case where the plate tower is horizontally placed or approximately horizontally placed, manual operations are facilitated, manual working is reduced, and the potential safety hazard caused by high-place operations is avoided.

Described herein is a device for upending a tubular element with a longitudinal direction from a support surface at an outer end. The device has a support beam which runs substantially parallel to the support surface and is connected to the support surface at a support point. The support beam guides a coupling tool to which a wall part of an outer end of the tubular element can be coupled. The coupling tool is displaceable relative to the support surface with the support beam, from a clear position to a coupled position in which the tubular element outer end is engaged by the coupling tool. Also described herein, in addition to the device, is a method which makes use of the device.