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By: Craig Pagano on September 13th, 2023

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Prevent Cylinder Contamination & Save Costs with Residual Pressure Valves

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Empty cylinders are often stowed away outdoors, where a variety of factors like temperature and humidity fluctuations can cause oxidation and eventual corrosion of the cylinder body. Any corrosion can decrease cylinder durability by risking contamination from external particles, which create further damage. (See our quick refresher on cylinder storage best practices here.)

One way to prevent contamination is for the filling operator to empty the cylinder by creating a vacuum inside the cylinder before refilling. Known as “cylinder purging,” this process takes both time and money, thus reducing efficiency and the cylinder’s overall lifespan.

The better solution? Install a residual pressure valve (RPV).

Benefits of RPVs:

  • Increased safety
  • Longer cylinder life cycles
  • More efficient and faster filling turnaround times

How RPVs work

The main purpose of the residual pressure valve is to protect the cylinder from contamination induced by foreign particles and impurities. 

When a cylinder is full, gas exits the cylinder and flows into the RPV cassette. A seal between the valve body and O-ring in the cassette blocks the gas. But when gas pressure builds up on the O-ring of the cassette, it pushes the cassette, which then pushes a spring. The seal breaks and gas can escape.

When a cylinder is empty, the RPV serves to maintain a set pressure inside the cylinder. This is what prevents contamination from moisture ingress or other atmospheric particles. When the remaining pressure inside the cylinder is below 4 bar, the force of the spring exceeds the gas force, and the RPV shuts off gas flow before the cylinder is empty.

Sherwood GSRPV


Sherwood GSRPV Series RPVs offer the highest quality and safety

Designed to protect cylinders and their contents without wasting time and money on unnecessary purge and clean cycles, Sherwood’s GSRPV Series residual pressure valves are made from precisely machined internal components and heavy-duty forged brass to meet the most stringent international valve performance standards. Automated assembly and testing processes ensure each valve performs exceptionally.

Sherwood GSRPV valves retain approximately 55 to 85 PSI pressure, which maintains the integrity of cylinder contents even if the valve is left open. Each valve is 100% helium leak tested, and features a Pressure Relief Device (PRD) with a unitized plug for excellent flow. Additionally, the dynamic front piston seal is not in direct contact with flow passage during filling. 

Designed to save you time and money, and expedite your filling cycles while protecting cylinders and their contents, the Sherwood GSRPV Series valves are top of the line in the industry.

Sherwood GSRPV


Key advantages:

  • Heavy-duty forged brass with precisely machined internal components
  • 100% helium leak tested
  • Surpasses stringent international valve performance standards
  • Eliminates need for purge-and-clean cycles
  • Maintains 55 to 85 PSI pressure, even if valve is left open
  • Prevents ingress of moisture
  • Pressure Relief Device provides excellent flow
  • Dynamic front piston seal prevents contact with flow passage
  • Inlet and outlet thread configurations
  • Optical Character Recognition (OCR) technology for easy verification of burst disc pressure
  • “Webbed washer” design protects burst disc during handling and bulk shipment
  • Multiple fill adapters available 
  • Inlets tapped (1⁄4" NPT) for dip tube as required

Shop Sherwood GSRPV Series Residual Pressure Valves


Need help choosing a PRV? We can help! Contact us today!