Why Scheduled Maintenance?


In everyday use hydraulic hose and assemblies are exposed to a series of stresses which makes it impossible to make a general statement about the service life of the hose.

To ensure constant accurate inspection levels the E.I & B.F.P.A utilise the same requirements as S.A.E. J1273 which recommends:

That hose assemblies are inspected for the following problems which is present require the replacement of the hose.

A. Leaks at the fitting or leaks in the hose.

B. Damaged, cut or abraded cover. 

C. Kinked, crushed, flattened or twisted hose.

D. Hard, stiff, heat cracked or charred hose.

E. Blistered, soft degraded or loose cover.

F. Cracked, damaged or badly corroded fittings.

G. Fitting slippage on hose assembly.

Standards and publications compiled by professional associations give directives for the service life of hydraulic hoses.

Recommendations of DIN 20066

At the time of mounting (assembly of couplings) the hose should not be older than four years.

The working life of the hose should not exceed six years including a possible storage of a maximum of 2 years.  However, in determined areas of application, the service life can be varied according to data of experience and specially considering the particular conditions of operation.  Any data differing from the norms have to be indicated in the instructions of use.

British Standards BS 5244

Gives a much more detailed recommendation:

Test recommendation for hose:

Up to 3 years - Use without further testing

3 to 5 years - Use after representative samples subjected to proof pressure testing

5 to 8 years - Use after representative samples subjected to proof, impulse and burst pressure tests and cold bend and electrical tests

Over 8 years - Scrap

Test recommendations for hose assemblies:

Up to 3 years - Use without further testing

3 to 5 years - Use only after subjecting each assembly to a pressure test of 1.5 x design working pressure and representative samples to a burst pressure test.

5 to 8 years - As above plus impulse pressure test and cold bend and electrical test on representative samples.

Over 8 years - scrap