The 800 feet of 30-inch HDPE pipe used in the Springfield, MO, project was fused using a McElroy TracStar 900 machine. The slipline process took only an hour.
Click here to enlarge imageButt fusion is the process of using heat and pressure to connect polyethylene pipes end to end. After the ends of the pipe are melted with a heater, the pipe ends are pressed together and held under pressure until the melt cools. The resulting fusion joint is proven to be as strong as the pipe itself, requiring no reinforcements.
“With fused joints, the pipe becomes a monolithic structure and has no joint,” said Tom Cravens, owner of Poly Pro. “HDPE has consistently proven itself in problem areas and bores.”
A cap was fused onto the front of the pipeline to prevent anything from entering the pipe during the operation. Entrance and exit pits were established. Bill Davis, owner of Davis Structure and Development Corp. and general contractor for the sliplining operation, decided to employ a pushing method by using a sling around the HDPE pipe that hooked to a backhoe bucket. The pipe was then pushed into the existing pipe until it emerged from the exit pit. Adapters were fused on the ends of the HDPE pipe so that it could be attached to the existing pipe.
“The insertion process took less than an hour and (the HDPE pipe) came out the other end relatively unscathed,” said Reed.
Reed estimated that the choice of HDPE saved the city $60,000, not including the expense that would have been required to refurbish the 10 backyards the line traversed. Manpower hours were also reduced by the speed of the project.
Three years after the initial 2005 slipline operation, Reed said Springfield continues to use directional drilling applications and HDPE for main installations in cul-de-sacs.
“It has given us the experience and trust in HDPE for other projects of a similar nature that might come up,” he said.WW
About the Authors:
Tyler Henning is a public relations specialist for McElroy Manufacturing, Inc. He can be reached at [email protected] or (918) 831-9286.
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