Working with high density polyethylene pipe is not difficult but it requires expertise to properly fuse the joints. In addition, if your project involves installing liner inside a pipeline, the process of HDPE pipe fusion is quite different from standard HDPE, due the smaller wall thicknesses. In fact, it’s best to use pipe technicians with the right equipment and training. But how do you choose the best subcontractor for the job? Let’s look a little closer and see.
What is Pipeline Fusing?
Whenever you are installing a system of pipes, you need a way to bond and seal the joints. Some types of plastic pipe like PVC can be glued. However, this is a misnomer because PVC is not glued it is solvent welded. A special solvent (not adhesive) is used and this soaks into and softens the surface of the PVC. Once pressure is applied it works like a heatless weld.
High density polyethylene is resistant to many types of solvents, so if you try to use standard adhesives or solvent products they will not work. Instead, a process which uses heat, called HDPE pipe fusion, is used. This method is often referred to as heat welding.
Fusing
In order to fuse polyethylene pipes (heat weld) both sections are placed inside a fusing machine. The machine is used to trim both edges so they will mate together perfectly. Both heat and pressure are applied and this forms the weld and flashing. Flashing is then trimmed off to provide a smooth outer surface.
Heat welding is best option for joining HDPE pipe because it is a thermoplastic material. Once melted it forms a tight bond and the pipe is as strong as if it were a one-piece section.
Things to Look for in a Subcontractor
When you search for a company to do your HDPE pipe fusion, consider these things:
* Certified technicians – ensures a higher quality of fusing and this is especially important for oil industry projects.
* Testing – your subcontractor should test every fusing bead to make sure it is perfect. A quality conscious subcontractor will reject any welds not up to standards and redo them. In addition to bead testing, a good technician will also air test on a regular basis to make sure there are no leaks in the system.
* High quality equipment – not all HDPE pipe fusion equipment is the same. Look for companies who use trusted brands like McElrory. This kind of equipment is also capable of data recording.