For instance, a digger derrick with a sheave height of 47 ft.

of boom reserve helps keep the pole hole as straight as possible. of the maximum digging radius, no matter what size the hole. Most operators set their derricks within 2- to 3-ft. Operators also have to know the pole specifications, including height, weight, and diameter in order to determine the best hooking point. The most important measure of digger derrick performance is called “load moment,” a calculation that considers boom angle, the distance from the derrick’s centerline of rotation to the winch line or auger, and the derrick’s lifting capacity.įor example, when an operator digs a hole for a pole, he or she must consider how far away from the truck they are going to dig, what kind of soil they’ll be digging in, and how deep and wide they will have to make the hole-all of which affect digging capacity.

The new work zone capacity standard is designed to help utilities and con- tractors do exactly that. Work zone capacity describes the ability of digger derricks to per- form the tasks they are built to do-digging holes and setting poles.įor digger derricks to be as efficient as possible, it’s imperative to understand and match the truck’s capacities to the range of work needed to complete the tasks that digger derricks are used for. To help customers accurately pick a digger derrick that has the size and power to complete real-world tasks efficiently without being oversized and expensive, Terex is promoting the “work zone capacity” concept as a new industry standard. That can lead to oversight in selecting equipment. The usual specifications and comparisons tell only part of the story, such as a digger derrick’s capacity at a 10-ft. In spite of that, no standard comparison lets customers easily match the size of a digger derrick to those working conditions. In fact, research shows that digger derricks spend 75% to 80% of their working time doing just those tasks. Most utilities and contractors use digger derricks to dig holes and set poles at 0° with the second boom section extended for most of the work day.

Boom truck lifting capacity chart