DESCRIPTION 
The Generant Series CRV SS, Stainless Cryogenic Relief Valve is a 
direct-acting spring reference over pressure protection device.  The 
Stainless CRV is supplied cleaned and packaged for oxygen service. 
The valve can be ordered with set pressures ranging from 10 to 750 
PSIG (0.7 to 51.7 bar) and comes factory preset and permanently 
locked.  Relief pressure cannot be altered or adjusted in the field.   
 
Seat and poppet geometry combined with optimized spring ranges 
provide high flow rates with minimum pressure accumulation.  
Compact design and availability of a variety of inlet and outlet 
configurations reduces size and piping requirements.  Relief pressure 
can be discharged to atmosphere or to a sealed downstream 
connection.  CRV SS can be ordered in a wide variety of seal materials 
depending on the desired set pressure and temperature. 
 
FEATURES 
• AVAILABLE CE MARKED: “CE Marked” to the Cat. IV 
requirements of the Pressure Equipment Directive (PED).  
• MULTIPLE CONNECTION STYES: NPT, Metal to Metal 
Face Seal and Dual Ferrule Tube Connections. 
• HIGH FLOW CAPACITY: See Flow Data next page. 
• CONFIGURABLE OUTLET: Discharge to Atmosphere or 
a Wide Variety of Sealed Outlet Pipe-A-Way Connections. 
• HYDROGEN COMPATIBLE: All Stainless Design with 
Spring Located Downstream of Poppet Seal. 
• SETPOINT PERMANENTLY LOCKED: Factory Pre-set 
and Permanently Staked for Tamper-Proof Service. 
• 100% FACTORY TESTED: Every valve is hand-tested for 
Leakage, Crack, and Reseat performance. 
• OXYGEN CLEAN STANDARD: All Valves Supplied 
Cleaned and Packed for Oxygen Service. 
 
TECHNICAL DATA 
Nominal Set Pressure Range:  10 – 750 PSIG (0.7-51.7 bar) 
Factory Set Tolerance: Set Pressure  ≤ 28.90 PSI, ± 5% 
                                   Set Pressure  29.00 – 48.30 PSI, ± 1.45 PSI 
                                   Set Pressure  ≥ 48.40 PSI, ± 3% 
                                   NOTE: Tolerance specifications per EN ISO 4126-1. 
Zero Leakage to 95% of Set Pressure 
Full Rated Flow by 110% of Set Pressure 
Reseat: 90% of set pressure OR 
              85% for PCTFE seals set below 100 PSIG (6.9 Bar) 
              85% for PTFE seals, any set pressure 
Flow Capacity unaffected by up to 10% Back Pressure 
Temperature Rating:  -425º to 392º F (-254º C to 200º C) 
    NOTE: Temperature ratings vary by seal material (see How To Order). 
     Valves are designed to be installed with a “vapor barrier” between the 
     cryogenic fluid and valve inlet.  See SA.TD.SSCRV001 for more info. 
 
Lubricant:  Krytox® 
      
MATERIALS OF CONSTRUCTION 
 
Component Material 
Body, Poppet, Seat Screw, 
Spring Retainer, In-Line 
Adapter1, Nuts and Ferrules 
316 Stainless Steel 
(ASTM A479)2 
Spring 302 or 17-7 PH Stainless 
Steel (ASTM A313) 
Seals 
PCTFE (ASTM D1430), 
PTFE, FKM or 
Fluorosilicone  
1 Inline Adapters utilize Viton® O-ring seals.   
2 Metal-to-Metal Face Seal connections are supplied Electro Polished to  
  10 Ra Max. 
NOTE: Viton® and Krytox® are registered trademarks of DuPont.