The Evolution of the Digger Derrick

Importance of Digger Derricks 

Digger Derricks are one of the most important multiskilled tools on a utility construction project. At first glance of these machines, it is clear to see they are built for a multitude of tasks- from digging holes and lifting and setting poles to turning screw anchors and setting transformers. 

These trucks are built for digging and lifting. Due to their multi-purpose design, they have adapted and evolved through engineering, development, and manufacturing to enhance work practices and work more efficiently.   

Before the Digger Derrick 

Before the digger derrick we see now-a-days was even a thought, crews were manually digging holes with shovels and hand augers. The poles were set by ropes and pure worker strength and will power to walk the poles into the correct positions. They then refilled the holes and tamped the ground by hand. 

What changed  

This was the way until the World War II-era created a need and desire to be a more global community and build the world’s power and communication grid. This created a need to quicken the line construction process, and that led to the first mechanical digger derrick being developed.  

Mass Production and Improvements 

In the 1940’s it began with Leroy C. Lindquist. He was the owner of the Minnetonka Manufacturing co. that made parts for the Telephone and Electric, known as Tel-E-lect. Lindquist got the opportunity to work with Northwest Bell Telephone Co. to develop a power-take-off runed machine to drill and lift the poles. This created the digger derrick truck concept we see today. 

This quickly turned into mass production of these trucks in the 50’s. Throughout that decade, the truck saw three major improvements that are still on the truck today: the-Rite-Way auger storage bracket, Pole Grabbing winch and the hydraulic collector block. In the 60’s and 70’s hydraulic derricks were refined. This allowed the design to be mounted on smaller chassis, which allowed the crews to become more mobile and adaptable with their fleets. It also helped create a more efficient workplace.  

Terex’s Involvement 

Terex purchased Tel-E-lect, the manufacturer behind the first digger derrick, made, and improvement milestones. They purchased the company from Simon Engineering. This became a huge acquisition for Terex Utilities, a business group within Terex Corp. In today’s world, Terex Utilities is one of the leading suppliers of digger derrick trucks. 

Today’s World 

One major change in the digger derrick design is the ability to position a worker in the air. This led to the ability to do pole top maintenance work. They are now able to replace cross arms, insulators, and power lines, as well as perform lifting operations if properly certified of water and gas components plus erecting signs and lights. Other interesting adaptations that have been made include radio controls which allow the machine to be remotely operated, fiberglass components to improve insulation safety. All this includes improvements for efficiency to the construction process of utilities. 

Terex has the history and future of being an industry leader and setting the standard, the digger derrick is an example of that with improvements throughout the last 75 years that created the ability to get the job done efficiently and safely.