Hydraulic Products, X65 Range - Premium ISO 16028 Flat-Face Quick Couplings

Series 665, DN16 Steel

  • Flat-Face design
  • One-hand operated
  • Extra security locking

CEJN Series 665 is a Flat-Face quick-connect coupling according to and exceeding the ISO 16028 Standard for low- and medium-pressure hydraulic applications. The Flat-Face design minimizes spillage during connection and disconnection. Series 665 couplings require only one hand for operation, making connection and disconnection fast and easy. Dust caps are available as accessories for both the coupling and nipple when disconnected to prevent dust and debris from entering the system. Series 665 couplings feature manual security locking as added protection against involuntary disconnection.


The couplings and nipples are also available in other sizes; DN 5 (Series 165), DN 6.3 (Series 265), DN 10 (Series 365), DN 12.5 (Series 565), DN 19 (Series 765), DN 25 (Series 065). Nipples with pressure eliminator available under Series 664.

Series 665, DN16 Steel
Technical data
Temperature range: -30°C — +100°C (-22°F — +212°F)
Material coupling: Steel (zinc passivation)
Material nipple: Hardened steel (zinc passivation)
Material seal: Nitrile (NBR/PUR, other sealing materials on request)
Max. working pressure connected: 400 bar (5801 PSI)
Max. working pressure disconnected: 400 bar (5801 PSI)
Min. burst pressure connected: 1200 bar (17404 PSI)
Min. burst pressure disconnected: 1200 bar (17404 PSI)
Connectability: Only limited by operator strength
Disconnection under pressure: Not allowed
Interchangeable with: All brands dimensionally interchanging with ISO16028

Rated flow is measured at 0.1 MPa pressure drop.

Pressure drop chart
Series 665, DN16 Steel
Couplings Part No. Connection Length Diameter Hexagon Seal
Female thread 10 665 1101106651101Rc 3/4" (BSPT)79.841.236NBR
 10 665 1201106651201G 3/4" (BSP)79.841.236NBR
 10 665 1211106651211G 3/4"79.841.236FPM
 10 665 14011066514013/4" NPT79.841.236NBR
 10 665 16011066516011 1/16"-12 UN (3/4" SAE)79.941.238NBR
Male thread 10 665 1551106651551M26x1.5 18L80.941.236NBR
 10 665 17521066517521"-14 ORFS bulkhead109.941.236NBR


Coupling for Panel mounting Part No. Connection Length Diameter Hexagon Seal
Female thread 10 665 1281106651281G 3/4" (BSP)79.841.236NBR


Nipples Part No. Connection Length Diameter Hexagon Seal
Female thread 10 665 6201106656201G 3/4" (BSP)74.939.236PUR
 10 665 6211106656211G 3/4"74.939.236FPM
 10 665 64011066564013/4" NPT74.939.236PUR
 10 665 66011066566011 1/16"-12 UN (3/4" SAE)754138NBR
 10 665 6101106656101Rc 3/4" (BSPT)74.94036PUR
Male thread 10 665 6551106656551M26x1.5 18L764036PUR
 10 665 67521066567521"-14 ORFS bulkhead10540.536PUR


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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