Parker Relief Valve

$229.52 / EA
  • Manufacturer: Parker Instrumentation
  • Product Family: RH4A Series
  • Application: Monitoring Line, Process Control Line, Research Equipment
  • Body Material: ASTM A182 F316 Stainless Steel
  • End Connection: CPI Single Ferrule Compr. x CPI Single Ferrule Compr.
  • Inlet Size: 1/4 in.
  • Outlet Size: 1/4 in.
  • Pressure Rating: 6000 PSIG CWP, 50 to 350 PSIG (Cracking)
  • Seal Material: Nitrile Rubber
  • Spring Material: 17-7 Stainless Steel
  • Temperature Rating: -30°F to 225 °F
Parker RH4A Series Relief Valve, 1/4" x 1/4", CPI Single Ferrule Compression x CPI Single Ferrule Compression, 6000 PSIG CWP/50 to 350 PSIG Cracking, 316 Stainless Steel, Nitrile Rubber Seal, Adjustable Pressure, Angle, Relief Valve.

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Product Description

Check Valve; Type In-Line, Poppet; Nominal Size 1/2 Inch x 1/2 Inch; Orifice Diameter 0.406 Inch; End Connection A-LOK Double Ferrule Compression x A-LOK Double Ferrule Compression; End to End Distance 3.37 Inch; Body Material ASTM A276 316 Stainless Steel; Cap Material ASTM A276 316 Stainless Steel; Spring Material 316 Stainless Steel; Seat Material Highly Fluorinated Fluorocarbon Rubber; Seal Material Highly Fluorinated Fluorocarbon Rubber; Temperature Rating -15 to 200 Deg F; Pressure Rating 6000 PSIG CWP, 100 PSI (Cracking); Inclusions/Features ASTM A479 Type 316 Stainless Steel Poppet; Application Uni-Directional Flow Control of Fluid and Gas, Chemical Processing, Oil and Gas Production and Transmission, Pharmaceutical, Pulp and Paper, Power and Utility, Back Flow Preventer; Hex Size 1.25 Inch and 0.875 Inch; Flow Capacity 2.65 Cv


Special Seat Seal Design Provide a Repeatable High Integrity Seal and Accurate Cracking Pressure; 100% Factory Tested; Heat Code Traceable; Color Coded Identification Labels Indicate Seal Material

Series/Model Information

Parker CO Series Check Valves are designed for uni-directional flow control of fluids and gases in industries such as chemical processing, oil and gas production and transmission, pharmaceutical, pulp and paper, power and utilities. The CO Series Check Valve is particularly suitable for applications requiring high integrity leak rates and re-sealing capabilities.


PTFE Back-Up Ring/Washer, 316 Stainless Steel Cap/Upper Stem/Bonnet/Lower Stem/Seat Retainer/Stem Guide/Handle Stem/Locknut, Nitrile Rubber Stem Seal/Seat, Zinc Plated Steel Plug, Phenolic Handle