At Beswick many of our new product design ideas originate from customer requests that are all in a similar vein. Sometimes if we receive enough feedback for a particular idea, we will begin development of a new product to add to our line. This was the case of our new high pressure miniature regulator, the PRD3HP. The new regulator will be joining our regulator line up officially in the next couple of months, but it presented several challenges as our Chief Engineer, Gary Treadwell, explains:

“Beswick Engineering has long held a prominent position in the miniature pressure regulator market. Typical applications are instrumentation, miniature robotic devices and fuel gas delivery in alternative energy systems. Fuel gas delivery systems have become particularly challenging applications due to increasing demands for precise regulation in a compact envelope. Also, these alternative energy systems often require high energy densities which necessitate the use of high pressure gaseous fuels. Early on, we recognized the need in the market for a miniature pressure regulator which offered precise pressure regulation at high pressure reductions while still maintaining a compact envelope. Thus, we embarked on the design of the PRD3HP two stage pressure regulator.

Miniature pressure regulators typically operate with inlet pressures under 500 PSIG. At these pressures, sealing is accomplished with relative ease. In fact, the second stage of the PRD3HP utilizes Beswick’s award winning valve design from the PRD2; a high precision, medium pressure, two stage pressure regulator. It was the first stage of the PRD3HP that presented challenges. The first stage of the PRD3HP regulator “roughs” down the high pressure gas to approximately 50 PSIG so the second stage can then precisely regulate the pressure to its final set point. As inlet pressures rise to 3000 PSIG sealing issues came to a forefront, especially with difficult to seal gasses such as hydrogen. Seal permeation, explosive decompression and mechanical seal failures were common problems encountered during the design phase.
Sealing was not the only issue. In miniature devices, the envelope can severely limit the engineer’s options in the design. Also, fabrication, assembly and testing must also be kept as simple as possible. The design must also allow flexible material selection in order to meet a wide range of unforeseen applications. We tried numerous iterations before settling on the current first stage valve design.

As challenging as the design was, the product release phase proved equally problematic. Where the prototypes worked flawlessly the initial production units had numerous issues with sealing and operation, all related to the functioning of the new first stage. These initial units required hand fitting and rework in order to work properly. The design drawings were revised in response to these problems but the difficulties persisted. After much head scratching, the root of the problems was found to be (of all things) the spring which sets the pressure of the first stage. After a custom spring was specified the problems went away.

The PRD3HP is now a valuable part of our extensive regulator line. It is available in a wide variety of materials, port configurations and cap configurations.”

Look for more information on the PRD3HP as it arrives in our up and coming catalog as well as the Beswick Engineering website.