This manufacturer has come up with an alternative method using its Superbell 250 belling machine to join plastic pressure water pipes by thermo-enlarging one end as the socket to allow insertion of the one pipe inside the other. This method is said to reduce costs and ease assemblers' work. It also allows for joining of pipes by workers of limited training without special welding equipment or accreditation. Valeria Giacomoni, Sica marketing manager, says the reason this joining technique was not previously marketed was because polyethylene (PE) pipes have a challenging mechanical behavior, often requiring different or special socketing processes, which are sometimes not well understood.
During socketing, Giacomoni says the solution lies in preventing the mechanical memory of PE from returning to its previous shape. With the Superbell unit, this is achieved by a combination of different warming processes. The unit has two ovens and creates a special process of forming and cooling the end of the pipe. It builds a seat for strong sealing made of an elastomeric gasket plus a plastic ring that grips under pressure and prevents pipe slippage. Model 250 is designed for pipes with a diameter of 50-250 mm and length of 2-12m. Sica SpA, Alfonsine (RA), Italy; +39 0544 88711; www.sica-italy.com
