Which tubing should I connect to a flat-bottom 5/16-24 UNF port, when and how?

5/16-24 UNF threads are popular thread types because they can be connected to both 1/8" and 3/16" OD capillaries with appropriate flat-bottom fittings.

3/16" OD capillaries are usually used for flow rates of a few liters per minute. Above this, 1/4" OD tubing is often used.

To integrate devices with a 5/16-24 UNF thread into 1/4" tubing systems, adapters are required.

The table below gives a recommendation for this.

In any case, make sure that the flow-through equipment is designed for the intended flow rates!

Flow rate regime Recommended tubing OD Small part recommendation to connect to 5/16-24 UNF port
Up to 100 ml/min 1/16" Adapter A7235 + fitting A58291 and ferrule A58292-1
Up to 500 ml/min 1/8" Fitting A7236 and ferrule A58294
Up to 3 000 ml/min 3/16"

Fitting and ferrule A142700

Up to 15 000 ml/min 1/4"

Adapter kit A70701



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