- FUSION EQUIPMENT
Typically, polyethylene pipe and fittings are connected by means of butt fusion, which is done by using a fusion machine that holds the pipe &/or fitting in a stationary position. A facer that has a cutting blade then trims the ends to be mated. A heater plate is positioned between the ends to be connected. The heater is then removed and the ends are brought together and allowed to cool.
By following the manufacturers’ recommendations for butt fusion, the weld becomes as strong as the pipe itself. It is even possible to pull several hundred feet or more of HDPE pipe after it has been butt fused together, since you actually have created a section of monolithic pipe.
Butt fusion creates strong, leak-free HDPE welds when following proper procedures. ISCO has hundreds of reliable, easy-to-operate McElroy machines for rent, and for sale. Machines to fuse from ½” to 65” HDPE pipe are readily available; various size and application-specific units noted below:
1/2” - 6”
6” - 20”
24” - 48”
52” - 2.5m
Electrofusion is a simple, cost-effective method for joining HDPE pipe. As an alternative to butt fusion, electrofusion is ideal for repairs and difficult connections of HDPE pipe. It has been successfully and cost effectively used for applications such as pipe bursting, slip lining, dual containment, directional drilling, and manhole connections.
Electrofusion couplings are available in a wide-range of sizes. Other fittings available in electrofusion are self-tapping tees, branch saddles, and high-volume tapping tees.
ISCO stocks electrofusion processors, including the Highland brand, for sale or lease at multiple ISCO locations.
Extrusion welding of HDPE is a typical welding procedure. Before welding begins, the surface of the polyethylene must be ground down, to expose the virgin HDPE. A spark test wire may be placed in the groove; this will be used to later test the quality of the weld. Now the extrusion gun is set in place and it begins to extrude a bead of molten polyethylene. Super-heated air is forced out the nozzle, melting the surface. Molten polyethylene is then forced out of the extruder, where it bonds with the surface. A spark tester is used to test the integrity of the weld seam. The extrusion weld creates a molecular bond between the sections of polyethylene.