GB 1186-92 Rubber Hoses for Compressed Air
This Chinese standard stipulates the requirements, test methods, inspection rule and marking, packing, quality certificate, etc., concerning rubber hoses for compressed air for automobiles and production machinery.
This standard is applicable to the rubber hoses for compressed air used in automobiles and production machinery, that is, in pressure pipe structure, the external rubber layer, internal rubber layer and reinforced layer of the hoses are composed of rubber or rubber materials; or in non-pressure pipe structure, the external rubber layer, internal rubber layer and reinforcing layer of the hoses are all made of rubber or rubber materials.
1. Scope of Application
1.1 GB 1186-92 rubber hoses for compressed air are applicable to the rubber hoses, which are used in the hose pipes of production machinery and automobiles, and whose external rubber layer, internal rubber layer and reinforcing layer are made of rubber and rubber materials.
1.2 This standard is applicable to the rubber hoses for compressed air.
1.3 This standard is not applicable to the rubber hoses for air pressure signals.
2. Normative References
The following documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, all subsequent modifications of or amendments to, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to investigate the possibility of applying the most recent editions of the standards.
GB/T 2876-1994 Rubber, vulcanized or thermoplastic — Determination of tensile stress - strain properties
GB/T 7983-1994 Rubber, vulcanized or thermoplastic — Determination of tear strength (angle and knife method)
GB/T 9571-1995 Rubber‑‑Determination of low‑temperature modulus and tensile strength
GB/T 1302-1991 Rubber, vulcanized or thermoplastic — Determination of hardness (hardness between 10 IRHD and 100 IRHD)
GB 1817-1995 Rubber hoses for hydraulic oil pressures
3. Terminologies and Symbols
The terms and symbols given in Table 1 and Table 2 shall apply in this standard.
Table 1 Terminologies
No. Item Terminology
1 Outer rubber layer The part of the rubber hoses, which directly contacts the air source.
2 Reinforcing layer Made of rubber or fiber cloth, metal wire and other materials. Its main purpose is to strengthen the structure of the rubber hoses.
3 Internal rubber The inner wall of the pressure type rubber hoses and all surfaces of the non-pressure type rubber hoses.
4 Adherence strength It refers to the maximum destructive load divided by the products nominal Cross-sectional area.
Table 2 Symbols
No. Item Symbol
1 Tensile strength f6 (MPa)
2 Elongation at break δ (%)
3 Hardness H (IRHD)
4 Tearing strength T (kN/m)
4. Type, Structure and Model
4.1 Type: The rubber hoses for compressed air shall be divided into pressure type and non-pressure type.
4.2 Structure: Thepressure type is composed of an outer rubber layer, reinforcing layer and an internal rubber layer. The non-pressure type is composed of anouter rubber layer and reinforcing layer.
4.3 The model of the product shall be generated on the basis of its structure, purpose, outer diameter and working pressure.
5. Requirements
5.1 Appearance: The surface of the rubber hoses shall be smooth and even, with no cracks or excessive leftover after processing.
5.2 Adherence strength: The average adherence strength of five specimens, the test results shall not be lower than the values specified in Table 3.
Table 3 Adherence strength
Specifedwork pressure Adherrengestroghth fornonpressure typehoses
(MPa) (MPa)
< 0.9 ≤0.19
Of 0.9 to2.3 ≤0.28
Of 2.3 to 8 ≤0.40
> 8 ---
5.3 Tensile properties: After being tested under room-temperature, the test results of each specimen’s tensile strength, elongation at break, tear strength and hardness shall not be lower than the values specified in Table 4.
Table 4 Tensile properties
Specifiedwork pressure Tensisetrength Elongaction atbreak Tearingstrength Hardness
(MPa) (MPa) (%) (kN/m) (IRHD)
< 0.9 ≥5.0 ≥400 ≥16 40-90
Of 0.9to 2.3 ≥7.5 ≥250 ≥12 40-90
Of 2.3to 8 ≥9.0 ≥200 ≥8 40-88
> 8 ≥10.0 ≥150 ≥6 40-88
5.4 Abrasion: The specimen originally 50 mm in length shoots a certain number of cylindrical test heads with a diameter of 16 mm at 6m per minute, and the test results shall not be lower than the values specified in Table 5.
Table 5 Abrasion
Specifiedwork pressure Burschgstrene
(MPa) (%)
< 0.9 ≥0.4
Of 0.9 to2.3 ≥0.6
Of 2.3 to 8 ≥0.8
> 8 ≥1.0
6. Test Methods
6.1 The adherence strength of non-pressure type rubber hoses shall be tested in accordance with the stipulations of GB 1817-1995.
6.2 The tensile properties, tear strength and hardness of rubber hoses shall be tested in accordance with the stipulations of GB/T 2876-1994, GB/T 7983-1994 and GB/T 1302-1991.
6.3 The low temperature bending property shall be tested in accordance with the stipulations of GB/T 9571-1995.
6.4 The abrasion shall be tested in accordance with the stipulations of GB/T 4178-1992.
7. Marking, Packing and Quality
7.1 Marking: The marking of rubber hoses shall include the manufacturers brand, size, type and working pressure.
7.2 Packing: The rubber hoses shall be packed in accordance with relevant stipulations of the rubber hoses’ product specifications.
7.3 QualityCertificate: The manufacturer shall issue a product quality certificate to the purchaser, specifying the product name, specification, type, quantity, working pressure, product implementation standard, test results, and signature of the responsible person.
