O-Rings $1.00 Minimum + Shipping from $6.99



PSC-334 3" Double Acting Piston Seal


Quantity Discount Prices

  • Model: PSC-334
  • 0 in Stock


The PSC double-acting crown seal is a squeeze-type seal utilizing an o-ring as a loading spring to seal the static surface. The crowned sealing surface produces positive seal from vacuum to high pressure due to narrow single line seal contact area. The side legs act as an anti-extrusion device for the o-ring as well as add stability to the seal. Being bi-directional, PSC seals are also used in slow speed rotary services. 

The shell is molded in polyurethane, ensuring flexibility for installation and performance at high/low pressures. 

The PSC crown seal is directly interchangeable with corresponding T-seal, standard O-ring, O-ring w/Back-up (1 back-up – Intermediate Base; 2 back-ups – Wide Base), and PSM seal grooves. 

A Nom ID 2-5/8
B Nom OD 3
C Nom Height .255
D Groove Width .280
O Ring Dash Number -334
H Groove Diameter 2.625
I Piston Diameter 2.997
J Bore Diameter 3.000


Material Type (Primary Seal): POLYURETHANE 

Material Type (Energizer): 70A NITRILE 

Durometer (Shore A): 95 

Temperature Range (F): -40 TO 248 

Extrusion Gap at Various Pressures (in):

  • 4,500 PSI: 0.008
  • 5,000 PSI: 0.006

Max Speed (ft/sec): 3.0 

Mating Surface Roughness - Ra (µin) - DYNAMIC: 4<>16 

Mating Surface Roughness - Ra (µin) - STATIC: 63 MAX