Twin sheet forming an air cell water pressure regulator

Twin-sheet formed ball absorbs water pressure irregularities

Twin sheet forming provides cost effective manufacturing solutions for many industries. One of the more unique projects Profile has worked on was a pressurized air cell for a water pressure regulator, which helped an OEM who experienced production interruption.

Pressure regulator project background

The OEM created a ball-style pressure regulator for commercial plumbing systems. Called a water hammer arrestor, the device acts as a shock absorber. The pressure inside allows the ball to deform as needed to absorb pressure waves in the plumbing. Smoothing the pressure prevents banging in the pipes.

A large manufacturer was contracted to make the waterproof ball component of the arrestor, since they worked with elastomer materials. The plumbing OEM paid for the tooling development.

A thermoformable yet flexible resin, TPU (thermoplastic urethan), was specified. The ball would be twin sheet formed and then die cut.

Tooling and quality challenges

Problems arose after production started. As the program matured, the initial ball manufacturer could no longer support the customer’s production and quality requirements. The OEM needed to look elsewhere.

Transfer tooling solution

The customer asked if Profile could handle the project’s specialized material and low volumes. Profile did have experience with TPU. Not all thermoformers have the capability to work with this unique material.

Since the OEM owned the tools, they could transfer them. The multi-cavity tools could work on one of Profile’s twin-sheet lines. Engineers made some changes to improve accuracy and throughput.

By working closely with the customer, Profile was able to effectively produce TPU air cells.

High performance results

Once the transferred tools were adjusted, Profile delivered parts with significantly improved yield. They also provided longer service life. The water hammer arrestor cell was in production for several years.