Fluid Products, Classic Couplings & nipples

Series 321

  • One-hand operated
  • Extremely high-flow capacity
  • Large range of connections

Featuring valved couplings and valveless nipples, Series 321 has superior flow capacity. Series 321 is suitable for a variety of fluid applications, such as water inlet and return for injection molding lines. A large range of connections is available in the series that requires only one hand for operation. Other sealing materials, such as EPDM, are availabe on request.


Series 321
Technical data
Nominal flow diameter: 7.4 mm (9/32")
Water flow (single shut-off): 78 l/min (17.2 GPM UK)
Max. working pressure: 35 bar (507 PSI)
Min. burst pressure: 140 bar (2030 PSI)
Temperature range: -20°C — +100°C (-4°F — +212°F)
Material coupling: Nickel-plated brass
Material nipple: Nickel-plated brass
Cv (single shut-off): 2.72
Kv (single shut-off): 2.34
Fluid flow
Pressure drop, bar (PSI)
Series 321
Flow, l/min. (GPM UK)
Couplings with valve Part No. Connection Seal Length Diameter Hexagon
Hose connection 10 321 10021032110026.3 mm (1/4")NBR6723.419
 10 321 10031032110038.0 mm (5/16")NBR69.523.419
 10 321 100410321100410.0 mm (3/8")NBR7023.419
 10 321 100510321100513.0 mm (1/2")NBR6823.419
Male thread 10 321 1152103211152R 1/4"NBR6323.420
 10 321 1154103211154R 3/8"NBR6123.420
 10 321 1155103211155R 1/2"NBR55.525.422
 10 321 1254103211254G 3/8"NBR56.523.420
Female thread 10 321 1202103211202G 1/4"NBR5723.420
 10 321 1204103211204G 3/8"NBR6025.420
 10 321 1205103211205G 1/2"NBR59.528.925


Nipples without valve Part No. Connection Seal Length Diameter Hexagon
Hose connection 10 321 50031032150038.0 mm (5/16")-44.513-
 10 321 500410321500410.0 mm (3/8")-44.513-
 10 321 500510321500513.0 mm (1/2")-44.517-
Male thread 10 321 5151103215151R 1/8"-351513
 10 321 5152103215152R 1/4"-38.516.214
 10 321 5154103215154R 3/8"-40.519.617
 10 321 5155103215155R 1/2"-4725.422
Female thread 10 321 5202103215202G 1/4"-3619.617
 10 321 5204103215204G 3/8"-37.523.120


Check with an authorized CEJN distributor for availability and prices. Other connections and sealing material on request. Some part numbers may be subject to minimum order quantities. CEJN reserves the right to make changes without further notification. Thread connections are listed according to ISO Standards. All measurements are in mm.

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