Circle Seal 5333T1-4PP Relief Valve
5300 Series: Adjustable Inline Relief Valves, 400 to 10,500 psig
Features:
- Zero leakage: up to 95 of cracking pressure
- No chatter or squeal: completely balanced; smooth, quiet operation at all flows; no chatter or squeal from pressure changes or surges downstream
- Positive reseal: repeatedly reseals at high percentage of the cracking pressure
- Virtually no pressure rise with increasing flow: design utilizes system back pressure on poppet to increase lift, providing excellent flow characteristics with little or no pressure rise
- Accurate set pressure: valves crack repeatedly at preset pressure with minimal variation; o-ring breakaway friction is overcome before valve opens
- Externally adjustable: external adjustment permits changes in cracking pressure to meet circuit requirements; interchangeable springs permit change of cracking pressure range
- PED certifications and CE marking available for most models: add “PED” prefix to the valve part number if required

Circle Seal 5333T1-4PP Relief Valve Technical Data:
- Description: 1/2″ FNPT Inline Relief Valve, 316SS/Neoprene construction, cracking pressures between 400 to 10,500 psig
- Service: Gas
- Maximum Operating Pressure: 10,500 psig
- Body Material: 316SS
- Seal Material: Neoprene
- Poppet Material: PCTFE (for cracking pressures up to 3074 psig) OR Polyimide (for cracking pressures above 3074 psig)
- Connection Size & Type: 1/2″ FNPT
- Cracking Pressure Range: 400 to 10,500 psig (REQUIRED SET PRESSURE MUST BE SPECIFIED)
- Flow at Cracking Pressure: 5 cc/min gas
- Reseal Pressure:
- Cracking pressures between 400-599 psi: 80% of cracking pressure
- Cracking pressures between 600-899 psi: 85% of cracking pressure
- Cracking pressures between 900-5999 psi: 90% of cracking pressure
- Cracking pressures above 6000 psi: 95% of cracking pressure
- Leakage at Reseal Pressure (Ascending Pressure): Zero from 0 psi to 95% of cracking pressure
- Leakage at Reseal Pressure (Descending Pressure): Zero at reseal pressure
- Temperature: -20F to +240F

Dimensional Information:
- Height (“B”): 7.01″ (for cracking pressures between 400 and 2299 psig) OR 8.48″ (for cracking pressures between 2300 and 10,500 psig)
- Hex (“C”): 9/16″ (for cracking pressures between 400 and 2299 psig) OR 1/2″ (for cracking pressures between 2300 and 10,500 psig)
- Height (“E”): 0.82″
- Hex (“F”): 2.00″
- Diameter (“G”): 1.75″
- Hex (“H”): 1.50″
- Diameter (“K”): 0.188″
Notes:
- Proper filtration is recommended to prevent damage to sealing surfaces.
- Cracking pressure tolerance is ±5%.
- Cracking pressure on initial crack after standing un-actuated for a prolonged period will be higher than the set pressure.
- The reseal point is the point at which the valve seals absolutely tight so that there is no leakage detectable by normal means of measurement.
Repair Kits:
- K/5333T14PP-A/E (for cracking pressures between 400 and 2299 psig)
- K/5333T14PP-F/H (for cracking pressures between 2300 and 10500 psig)
Please contact our Sales Department for assistance in selecting the right products for your application.
Product Catalog: Circle Seal Relief Valves
Service Information Sheet: Circle Seal 5300-Series Relief Valves


