A question about the pressure ratings of Camlock fittings was posted in the Discussion Forum section of our Members Area. Stan Merrett (ETT, LLC) was kind enough to provide some information on Camlock style fittings for use on pressurized hose lines when loading tankers...so we decided to share that info in a News Story.

Stan's info is presented below:

Pressure Ratings for Camlock (Quick Connect) Fittings.

These fittings were originally made for the military and are machined to Mil Standard C-27487. Buyers must be aware of imported brands as those items may not be machined to the Mil Standards.

Max allowable working pressures are as follows:
1/2" thru 2" 250 psi
2 1/2 - 3" 200 psi
4" 150 psi
5 & 6" 75 psi
8" - 12" 50 psi

Usually the connection to the hose is the failure point. ETT uses couplings that are machined with fire threads on one side and Cam & Groove on the other side. This way you are relying on the mfg'd fire hose for the coupling. Mr. Merrett prefers "P.T. Coupling" fittings as they provide fittings which thread directly onto a fire hose thus...converting it to the Cam & Groove.

Stan has been using the coupling for over 30 years and never had a problem with pressure. He does caution users to close the pressure source valve before releasing the Q/C Valve. If not, it will occasionally blow the gasket out of it's groove and you may get wet releasing under pressure. Stan recommends carrying an extra gasket on your tanker just in case.

The Camlock couplings are easily found and fairly cheap compared to many other fire hose fittings.
In Stan's area of Alabama, they pretty much have standardized filling with (2) 3" fill hoses converted to 3" Cam & Groove. (Several of the photos are courtesy of Stan Merrett.)