How to choose 5 common pneumatic quick connect interchange profiles in use in the USA

There are 5 common pneumatic quick connect interchange profiles in use in the USA today, and one relic oddball.

They are the ISO 6150B or Industrial profile (Milton “M”)

the Truflate profile (Milton “T”)

the ARO 210 profile (Milton “A”)

and the European 7.2mmHigh Flow (Milton “V”)

The last is the Lincoln “long nose” profile.

To select the type of profile for your application, you need to consider the following:

How much airflow?

Durability and material.

Ease of use?

For airflow, the coupling system needs to be rated according to a standard parameter set. Normally 100 PSI applied, with the flow in CFM rated at 10 PSI drop across the coupler/plug. The high flow design is best, flowing about 70 CFM, Industrial profile and Truflate next at about 32 CFM, and ARO 210 at about 28 CFM. The Lincoln profile will flow about 22 CFM at best.

For durability, you need to look at the plug materials and the internal seals in the coupler. Plugs need to be hard and resistant to deformation when dropped. They need to be made of steel and should not scratch when a file is pushed across the end. Plugs and some others are made of hardened steel. Aluminum and brass plugs deform easily and will damage the seals inside the couplers, and should not be considered in most instances. The couplers need to utilize an o-ring seal that seats on the barrel of the plug. Many inexpensive couplers use a flat gasket that is prone to leaks.

In operation, most couplers use a spring-loaded locking sleeve that needs to be retracted then pushed forward to lock the plug in place, often a two-hand operation, and this can be difficult with air pressure applied. Some couplers are “push to connect” operation but still use a sleeve to disconnect. Sleeve couplers are notorious for popping off when dropped or slid across the floor. Now push-button safety coupling and universal coupling are also good choices.