Technical information
How to Determine the Correct Installation Length?
Total Assembly Length
Hose Cut Length
For most installations, the correct installation length can be determined by direct measurement or a sketch of the equipment. The minimum bend radii shown in the hose specifications tables must be adhered to. Assemblies are measured to the end of the seal. To determine the length of tubing needed when installing with permanent or reusable couplings, subtract Dimension "C" (Cut factor) for each coupling from the total assembly length required. Dimension "C" can be found in the coupling specification tables.
How Are Assemblies Measured?
Length Over Nipple
Length Between SP and Nipple Tips
Note that the hydraulic hose under pressure will stretch up to 2% of its length or shrink up to 4%, depending on the pressure, type and size. Sufficient allowance should be made to allow for such changes in length.
Insufficient length of hose assemblies to allow adequate flexing, expansion or contraction will result in poor power transmission and shorten hose life. The diagrams below provide recommendations for proper hose installations to achieve maximum performance and economy.
Provide sufficient slack for expansion and contraction as the length of the hose can vary from +2% to -4% under high pressure surge.
It is very important to distribute sufficient hose length. It is used to prevent movement and wear in the stretching parts.
To prevent kinking in hose lines bent in two planes, clamp the hose at change of plane as shown.
Avoid sharply bending or twisting the hose by using suitable angled adapters.
To avoid bending, the hose must be bent in the same plane as the movement of the protrusion to which it is attached.
Where the radius falls below the minimum required, an angle adapter as shown above should be used to avoid sharp bends in the hose.
The hose must not be bent. The hose weakens when installed in the bent position. Also, the pressure in the bent hose tends to loosen the fittings. Design so that the machine movement produces bending rather than torsion.
Due to changes in length while the hose is under pressure, do not clamp at the bends so the curves absorb the changes and protect the hose with a spring guard. Do not clamp the high and low pressure lines together and protect the hose with a spring guard.
Never use a bend radius less than the minimum value shown in the hose specification tables. Avoid sharp bends in the hose to reduce line collapse and flow restriction by using appropriate spring protection. Exceeding the minimum bend radius will greatly reduce the life of the hose assembly.
