Quick-Open C-L Flange Couplings

Since it pioneered the concept in the 1960s, MMC has been the world’s leading manufacturer of cam-locking, quick-opening flange couplings for use in the transport of industrial liquids such as petroleum and chemicals.

C-L COUPLINGS with Built-in Safety Ratchet Lock

Ratchet C-L couplings provide quick, safe connections on a wide range of applications: Both marine and dockside hoses, manifolds, loading arms, valves. Each corrosion-resistant coupling (depending on its diameter) contains from three to ten helical cams. Each ratchet cam is individually locked into place so that it cannot be loosened without a special wrench (see below). A typical 3-cam connection is completed in less than a minute.

Here a ratchet C-L coupling (studded configuration) is bolted to an existing ASA hose flange for a one-time permanent installation. The coupling is then ready to be joined to a matching flanged hose, manifold or pipe of comparable diameter.

Secure the matching flange to the C-L coupling by rotating each cam to a hard stop using the bronze spanner wrench which is supplied.

The dedicated wrench tightens each helical cam with a wedging action that in turn compresses the O-ring seal, preventing cam from opening.

Standard Configurations

Standard C-L coupling configurations include studded end, short spool piece and weld-neck. Studded end couplings are designed to fit on existing flanges, with studs projecting out the back of the C-L flange. Weld-neck couplings are designed for welding directly to a pipe, saving the cost of an additional mounting flange.

Special Offshore Floating Hose Flange Coupling

A special spool piece flange coupling (above, views A & B) is now available for floating hose operations in the offshore loading industry. The spool piece unit is designed for tight area manifold extensions, hose lifting points and reducer couplings. It features special lifting pads, cam guard ring and enhanced corrosion resistant qualities required for offshore applications. As options, MMC also offers a studded type C-L coupling (above, C) that can be attached to a customer-supplied standard spool piece, or an optional C-L coupling with stud lengths long enough to bridle a butterfly valve and floating hose flange end. Both of these alternate configurations have the same enhanced corrosion feature as the spool piece type.

Vapor-Control Version for Maritime Tankers and Barges

C-L Couplings for use in maritime vapor recovery operations feature a special lug pin to prevent a vapor collection line from being inadvertently connected to a cargo line. The special pin on the shipboard flange only fits into an opening found in the land end of the correct coupling. This configuration conforms to all ANSI standards. C-L vapor-control couplings are also colored bright yellow to further prevent misidentification

Meet or Exceed Standards

MMC flange couplings are built to 150 psi or 300 psi ANSI standards and tested as leakproof to 1 1/2 times maximum working pressure (450 and 1110 psi, respectively). They also can be built to meet DIN and JIS standards and are approved by regulatory agencies around the world, including the U.S. Coast Guard, which has approved C-L ratchet couplings for inland and coastal waterways. C-L flange couplings are classed as pressure vessel equipment that meet the requirements of the Boiler and Pressure Vessel Code Section VIII, and the Welding and Inspection Section of the American Society of Mechanical Engineers (ASME) standards.

Wide Range of Flange Dimensions and Construction Materials

CL-flange couplins are available in sizes 4″ – 20″ costume sizes and configurations are also available to meet any need. A detailed C-L flange dimensional can be sent upon request via phone, fax or e-mail. 

SPECIFICATIONS (Standard Studded C-L Coupling Applications)

  •  Flange type (Studded): 150# ANSI, steel type 316SS ASTM A-182.
  • Flanged Spool type: 150# ANSI, forged steel, ASTM A-105, nickel plated cam side face.
  •  Nut Blocks: Steel, ASTM A-216, WCB.
  • Cam: High strength stainless steel, ASTM A-487 alloy CA-6NM.
  • Cam Bolts: High strength steel, ASTM A-311, nickel plated.
  •  Studs and Nuts: ASTM A193-B8 and A194-8A, UNC thread, type 304 stainless steel.
  •  O-Ring: Buna-N (1 installed) standard, 1 spare.
  • Cam Bolts Grease Fittings: Stainless steel type 304.
  • Cam Locking Wrench: Manganese bronze, ASTM B-147, Alloy 8A.
  • Painting Schedule: o Primer: Red oxide alkyd enamel o Finish: Jotun Pilot II #39W72 enamel blue-gray tint #F-23 o Interior: Black gloss waterborne enamel
  • Pressure Testing: 450 psi (32 kg/cm squared).

SPECIFICATIONS (Floating Hose C-L Coupling Applications)

  • Flanged type (studded): 150# ANSI, steel type 316SS ASTM A-182.
  • Flanged Spool type: 150# ANSI, forged steel, ASTM A-105, nickel plated cam side face.
  • Nut Blocks: Steel, ASTM A-216, WCB.
  • Cam Bolts: High strength steel, ASTM A-311, nickel plated.
  • Cam: High strength stainless steel, ASTM A-487 alloy CA-6NM.
  • Studs and Nuts: ASTM A193-B8 and A194-8A, UNC thread, type 304 stainless steel.
  • O-Ring: Buna-N (1 installed) standard, 1 spare.
  • Cam Bolts Grease Fittings: Stainless steel type 304.
  • Cam Guard Ring: Steel pipe, double extra strong, ASTM A-106.
  • Cam Locking Wrench: Manganese bronze, ASTM B-147, Alloy 8A.
  • Painting Schedule: o Primer: Red oxide alkyd enamel o Finish: Jotun Pilot II #39W72 enamel blue-gray tint #F-23 o Interior: Black gloss waterborne enamel
  • Pressure Testing: 450 psi (32 kg/cm squared).