The Altec DT65H Transmission Digger Derrick is a fully hydraulic, pilot-operated derrick that incorporates a high-flow piston pump into the hydraulic system. Because a single variable displacement piston pump provides flow, the maximum flow is available to any function. The result, according to Altec, is superior functionality, including four-function boom operation.

Hydraulic System Delivers More Functionality

The available hydraulic flow allows the operator to easily demand three or more functions without seeing speed or performance diminish, the company said. A 15,000-ft.-lb. auger motor also permits the derrick to dig in a wide variety of soil types.

This unit is a continuous rotation, heavy-duty transmission digger derrick designed with steel load-bearing structures. The DT65H features a fiberglass third-stage boom and boasts a 21,051-lb. lifting capacity at a 10-foot load radius.

The impressive lifting capacity “gives some indication of the operator’s ability to dig a hole, and lift and set a large transmission pole with just one unit set up,” said Chris Barnes, Altec market manager. “This increases productivity and efficiency on the jobsite.”

There are 360 degrees of ingress and egress to the riding seat. A popular option is the full-view riding seat, which provides easier riding seat accessibility and boom tip visibility at low boom angles.

Additional benefits of the Altec DT65H’s hydraulic system include a 50% reduction in heat generation during heavy digging, a 20% reduction in heat generation during continuous winch operation, and greater fuel efficiency compared to other derricks, Barnes said.

An Upper Boom with Extra Durability

The upper boom is a high-density, rigid, wound fiberglass-reinforced boom.
“This is a full capacity, hydraulically extending boom that can be used to lift the full capacity of the derrick in any position,” Barnes explained. For example, the intermediate boom may be fully retracted so that the upper boom functions in its place.

During manufacturing, the inside surface on the fiberglass extension is coated to resist moisture and foster water beading. The fiberglass boom has an external gel coat surface with ultraviolet ray inhibitors blended in to prevent weather deterioration. Each fiberglass boom is dielectrically rated to 46 kV AC and below.

Additional DT65H features include five-function hydraulic overload protection, hydraulic side load protection, transferable steel boom flares, a 15,000-lb. planetary winch, and hydraulic tilting pole guides with pole guide interlock.