Look in the toolbox of any successful contractor and you will see some of the reasons why they are successful. Aside from the other essentials for success, skill, dedication and commitment to quality, a contractor’s toolbox can give a keen insight into why they are successful. Since its beginnings in the 1960s, utility contractor Potelco, Sumner WA, has seen many changes. The assortment of tools in its toolbox has changed with the times, as well as Potelco’s expanding service offerings. One tool in particular has evolved from a novelty into an essential piece of equipment—the piercing tool. According to Gas Operations Manager Mitch Bogrand the tool is an important part of daily operations. He said, "We use pneumatic piercing tools for a wide range of applications including gas, electric and phone. For our gas service line installations we rarely use anything else. It’s just so much nicer then tearing up someone’s yard, their sprinkler system and grandma’s rose bush." According to Scott Langfeldt, piercing tool specialist from trenchless equipment manufacturer TT Technologies, Aurora, IL, Potelco really gets the most out of their piercing tools. He said, "The folks at Potelco are utilizing piercing tools to the utmost. Those tools are in the field day in and day out performing bore after bore. The piercing tool has unquestionably helped make Potelco one of the leading utility contractors in the United States."
37 Years
of Service With a staff of project engineers, Potelco is a design/build contractor. Potelco offers its clients comprehensive project planning including construction design, projected costs of materials and labor, and the construction of the project itself. Bogrand said, "We specialize in designers who are field oriented and who understand how design affects construction and future maintenance of the overall project. Often those designs include the use of trenchless technology, specifically piercing tools. We own and operate over 200 of them from one and three quarters to five inches in diameter." Accuracy
is Key According to Langfeldt, that improvement accuracy comes from improved design. He said, "While the Grundomat [piercing tool] basically works on the same principles found in the first piercing tools, the major improvement comes in the reciprocating head. A piston inside of a casing generates power. The piston drives the tool, and air drives the piston. Today’s conventional piercing tools, as well as the Grundomat, operate in this fashion. The Grundomat’s reciprocating chisel head assembly, however, moves independently of the main casing, creating a pilot bore for the rest of the tool body to follow. This ultimately leads to greater bore accuracy over conventional tools. The chisel like action helps the tool to power through difficult soils and obstructions without being pushed off course."
On
the Job Training Bogrand said, "We put new crewmembers with an experienced person. They seem to grab onto very quickly. It is a basic process, but there is a feel for the ground conditions and how the tool is going to run that you can only develop through experience." Potelco’s crews see a wide variety of soil conditions. Soils types include sandy loam, clay and rocky. With such a variety of soil types, crews rely on the accuracy and dependability of their piercing tools. Accuracy is a necessity to ensure efficiency. Bogrand said, "Well I’ll tell you in ideal ground conditions we’ve done 200-foot bores. That’s usually in an extensively landscaped situation where we’re running tool fairly shallow in good ground conditions. If it’s running straight and true we’ll just go ahead and keep adding hose. The guys call them glory shots. Most of the time, though, typical installations range between 40 and 70 feet." Typical
Installation Bogrand said, "The soil conditions in the area are very unforgiving. In addition, we had to deal with a nicely landscaped area and several changes in elevation, so we decided to divide the run into sections. The first shot went from the main under the sidewalks and the street, approximately 50 feet. After that we divided the subsequent shots into 40-foot lengths." The three-man Potelco crew used a 2-inch diameter Grundomat-P 55 from TT Technologies for the job. After the first shot under the road, the crew disconnected the air hose from the tool and compressor. At the launch pit a pipe pulling cable was connected to the hose and pulled into the completed bore path as the crew removed hose at the exit pit. At that point, the exit pit became the launch pit and a new exit pit was excavated approximately 40 feet away for the next bore. Each pit measured approximately 3 feet wide and 6 feet long at varying depths throughout the run. After each bore the crew repeated the process of pulling in pipe pulling cable, connecting each section of cable together once in place. After the series of bores to the mall was completed, the Potelco crew pulled the new 300-foot, 1 1/4-inch service in place with the pipe pulling cable. According to Bogrand each bore took approximately 20 minutes to complete. Once installed, the crew tied the line in the steel gas main using a welded service tee with a transition for plastic pipe. Piercing
Tool Praise You can put it in the ground and get it on its way and the crew can be doing something else. The crew can be working on the tie in or something like that. It’s always moving; it’s like having another person on the crew." Underground Construction, October 2001 |
