BS ISO 4079:2020 pdf download.Rubber hoses and hose assemblies - Textile- reinforced hydraulic types for oil-based or water-based fluids - Specification.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 8330 apply.
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4 Classification
Five types of hose are specified, distinguished by their construction, working pressure and minimum bend radius.
— Type 1TE: hoses with a single braid of textile reinforcement.
— Type 2TE: hoses with one or more braid(s) of textile reinforcement.
— Type 3TE: hoses with one or more braid(s) of textile reinforcement (higher working pressure).
— Type R3: hoses with two braids of textile reinforcement.
— Type R6: hoses with a single braid of textile reinforcement.
NOTE Type 1TE is not subjected to the impulse or vacuum resistance test. Type R3 is not subjected to the
vacuum resistance test. Type R6 is not subjected to the impulse or vacuum resistance test.
5 Materials and construction
51 Hoses
Hoses shall consist of a rubber lining that is resistant to oil or water-based hydraulic fluids or water, one or more layers of suitable textile yarn and a weather- and oil-resistant rubber cover.
Hoses shall be designed to enable end fittings to be assembled without removal of the cover.
5.2 Hose assemblies
Hose assemblies shall be manufactured using hoses conforming to the requirements of this document.
Hose assemblies shall be manufactured only with those hose fittings whose correct functioning has been verified in accordance with Z2, Z4, and 7. The manufacturer’s instructions shall be followed for the preparation and fabrication of hose assemblies.
6 Dimensions
6.1 Hose diameters and hose concentricity
When measured in accordance with ISO 4671, the inside and outside diameters of hoses shall conform to the values given in Table 1.
When measured in accordance with ISO 4671, the concentricity of hoses shall conform to the values given in Table 2.
7.4 Resistance to impulse
There shall be no leakage or other evidence of failure before reaching the specified number of cycles.
This test shall be considered a destructive test, and the test piece shall be discarded after the test.
7.4.1 Oil-based fluid impulse test
The impulse test shall be performed on hose types 2TE, 3TE and R3 in accordance with ISO 6803 or ISO 6605, using oil-based hydraulic fluid as required by ISO 6803 or ISO 6605, at a fluid temperature of 100 °C.
The impulse test is not required for types ITE and R6.
For type 2TE hoses, when tested at an impulse pressure equal to 125 % of the maximum working pressure, the hose shall withstand a minimum of 100 000 impulse cycles.
For type 3TE and R3 hoses, when tested at an impulse pressure equal to 133 % of the maximum working pressure for hoses of nominal size up to and including 25, orat 100% of the maximum working pressure for hoses of nominal size greater than 25, the hose shall withstand a minimum of 200 000 impulse cycles.
There shall be no leakage or other evidence of failure before reaching the specified number of cycles. This test shall be considered a destructive test, and the test piece shall be discarded after the test.BS ISO 4079 pdf download.