Hose and Coupling Knowledge Base

Leaks and disconnections from the connecting part may lead to serious accidents and should not be ignored.

Why do such leaks and disconnections occur?

There are two main causes.

The first is hose deterioration. The other is the selection of the coupling and hose.

Hoses are initially flexible and elastic, which helps hold the hose on the coupling and prevent fluids from leaking.

When connecting a hose to a coupling, the hose is inserted into a nipple slightly larger in diameter than the inner diameter of the hose. This causes the hose to stretch slightly, and the natural tendency of the hose to shrink back to its normal size provides a powerful grip.

Over extended use, however, the elasticity is gradually lost and the hose becomes stiff so it does not adhere as closely and the fluid can leak out. The same applies to situations where a hose is held on with a clamp. Even if the initial connection is perfect, leaks and disconnections may occur.



When the elasticity of the hose weakens, regular maintenance must be performed, including tightening the clamp.

As mentioned above, the selection of the hose and coupling is an important factor in leaks and disconnections.

A single manufacturer will have multiple hose and coupling sizes for each model. If the fit is loose, leaks and disconnections will begin right away, but if the fit is too tight, the load on the hose will hasten hose degradation, resulting in early leaks and disconnections. Refer to the table below for appropriate hose and coupling sizes.



The differences in “ease of insertion” and “leak / disconnection strength” can be seen in the video.



In any case, a clamp used for a barb fitting is unstable and may cause problems. To avoid such problems, Toyox has developed couplings exclusively for Toyox hoses.

Feel free to give us a call for assistance in selecting a product or consultation on a problem in the workplace.