TPi September 2018

Welding technology

Bespoke cold welding solution streamlines tube production

It’s faster, easier to standardise, and requires less operator input and training. Most advantageous of all, the new weld is stronger and capable of handling the tensions we place on the strip during tube production.” Before approaching PWM, VPT tried alternative methods of joining strip such as brazing, dovetail profiles, lap joints and laser welding. PWM successfully test-welded VPT’s strip using a portable ST40 cold pressure welding machine, capable of joining copper strip as wide as 45mm and as thin as 0.2mm. Precision engineered to create reliable permanent welds stronger than the parent material, the ST40 enabled VPT to reduce scrap by about 1.5 per cent during production trials. PWM has now supplied VPT with three ST40 welders that run full-time in production. Adaptations such as automatic flash trimming and annealing of the weld (to soften it and make it less brittle), and automation of the weld cycle and die

A customised cold welding system developed by British company PWM (Pressure Welding Machines) in partnership with US manufacturer Virtus Precision Tube (formerly Luvata) has streamlined and improved the process of copper tube production. The system has improved uptime, reduced costs and created a better working environment for operators, according to Joe Napier, VPT’s engineering programme manager. “We produce over 40 million pounds of roll-and-weld copper tube each year, in sizes from ¼" to ½",” he said. “The cold welding system we have developed with PWM is part of our continuous improvement programme. It supports our ongoing drive to develop high- performance tubing solutions for the HVAC and refrigeration heat exchanger markets. “The new cold welding process is more straightforward than the cross- weld process we used for a decade, and works the first time, every time.

opening system have been developed to streamline the process. VPT will field the new system across all tube mill production lines, and currently has four more ST40 units on order, with more to follow. “Technical assistance from PWM, particularly from its chief design engineer, Ivan Turner, has been incredible throughout,” said Mr Napier. “Any problems we had during the development and early fielding of the units were quickly resolved. For example, we went through four design improvements to arrive at our current tooling.” Pressure Welding Machines Ltd – UK pwm@btinternet.com PWM’s ST40 air-hydraulic cold welder for strip tape

www.coldpressurewelding.com Virtus Precision Tube – USA www.virtustube.com

IR fusion equipment for plastic piping Thermoplastic fluid flow technology company Asahi/America, Inc has introduced the latest innovation in automated infrared welding: the SP 110-S V3 combines repeatable and reliable IR welding technology with an efficient design, numerous enhancements, and new features. The SP 110-S V3 features a larger touchscreen and the latest electronic hardware. A higher memory and data capacity allows for storage of 20,000 welds and 42 custom weld parameters. Asahi/America’s Poly-Flo ® co-extruded double-wall pipe parameters are embedded in the standard parameters.

The V3 has been redesigned for increased automation, improved electronics and versatility. Its planer and heating element retract to provide a clear view of the weld and 360° access to the weld area. The overall weld process has improved automation, providing greater weld efficiency. The transport box is now more compact and functions as an integrated work bench with storage for all accessories. The machine is easily accessible and has been optimised for safe set-up in clean rooms.

The V3 also includes all of the core features of Asahi/America’s SP Series IR welding equipment, including automated force control welding and adjustable planing and alignment controls. Suitable for shop or clean room operation, the SP 110-S V3 welds 20 to 110mm (½" to 4") single- and double-wall pipe, including PP, PPn, PVDF, PE 100-RC, ECTFE and PFA. Asahi/America manufactures corrosion- resistant thermoplastic fluid handling

Asahi/America’s SP 110-S V3

products, including valves, actuators, pipe and fittings. Asahi/America, Inc – USA www.asahi-america.com

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September 2018 TUBE PRODUCTS INTERNATIONAL