Testing Hydraulic Hose Assemblies
Coupled hose assembly lots should be sampled and tested utilizing an acceptable burst and proof pressure procedure. It is recommended that proof and burst testing be performed in accordance with SAE J517 and SAE J343 or an applicable industry standard or customer specification.
The SAE J343 standard gives methods for testing and evaluatinig the performance of the SAE 100R series hydraulic hose and hose assemblies (hose and attached end fittings) used in hydraulic systems.
Proof Pressure Test
This proof test is conducted at twice the working pressure of the hose unless otherwise specified by the customer. The test pressure shall be maintained for a period of not less than 30 seconds or more than 60 seconds. There should be no indication of failure or leakage.
Hose Assemblies on which the end fittings have been attached less than 30 days shall be subjected to a hydrostatic pressure increased at a constant rate so as to attain the specified minimum burst pressure within a period of not less than 15 seconds no more than 30 seconds. There shall be no leakage, hose burst or indication of failure below the specified minimum burst pressure.
WARNING: Water or another liquid suitable for the hose under test shall be used as the test medium. The use of air or other gaseous materials as testing media should be avoided because of the risk to operators. In special cases where such media are required for the test, strict safety measures are imperative. Furthermore, it is stressed that when a liquid is used as the test medium, it is essential that all air is expelled from the test piece because of the risk of injury to the operator due to sudden expansion of trapped air released when the hose bursts.
The hose assemblies to be bench tested must be inspected to ensure conformance to applicable test specifications. It is important to realize that, with the exception of proof test and change in length, all hose assemblies under pressure testing are to be destroyed after the test.
Specific test and performance criteria for evaluating hose assemblies used in hydraulic service are in accordance with the requirements for hose in the respective specifications of SAE J517. It is recommended that every facility making hydraulic hose assemblies have a copy of the HS-150 standards manual.
Test methods for threaded hydraulic fluid power connectors shall conform to SAE standard J1644. This is equivalent to ISO 8434-5 with the exceptionthat the SAE standard includes “repeated assembly test” for male flare shaped fittings assembled to tube flare.
The same cautions apply to tube testing as with hose assemblies. Burst and fine jets can penetrate the skin. Sudden energy release can be very hazardous.
© Copyright 2012 by the Association fo Hose & Accessories Distribution, Inc. (NAHAD)