If a hose assembly has been removed for replacement and shows signs of leakage, corrosion, abrasion, or having been kinked or twisted. In this case, the initial installation was probably improper.
- In most hose assembly applications, it is advisable to protect, restrain, or guide the hose to avoid unnecessary flexing, pressure surges, and contact with other components. First, bend radii must be considered. The bend should be as generous as the installation space will allow, but in no case should it be less than the manufacturer’s spec.
- Protective devices are available and are often used for special installations. These are internal support coils, abrasion sleeves, and various types of clamping. These all have specific functions and should be used when required.
- The use of hose clamps, as the installation warrants, is essential. A hose clamp is designed primarily to separate the assembly from the adjacent line and aid in routing. The clamps should be snug enough to hold a line, yet not so tight that they cause line restriction at the point of contact. All hose assemblies should be installed with a slight bow or slack to permit growth and contraction.
- Parallel hose lines are often clamped together to improve appearance and function. Although the hose assemblies are, in a sense, operating together, each line is subject to its requirements.
- When installing hose assemblies, connect the most inaccessible end of the hose and tighten only “finger tight” so the hose is free to turn during installation of the opposite fitting. Attach the other fitting the same way. Then properly orient the hose along its routing and install the support. Ensure to distribute hose slack between the hose clamp and fitting connections. The hose should not restrict travel or cause the hose line to be subjected to tension, torsion, compression, or shear stress during its flexing cycle.
Once this procedure has been followed, tighten the end fittings, ensuring you do not twist the hose. Next, use two wrenches, one on the swivel nut and one on the nipple hex.
Individual judgment and skill on the part of technicians are ultimately the determining factors of a successful installation.