This standard specifies the method for conducting a flexure hydraulic impulse test on a hose according to the test parameters specified in GB/T 5568. This standard applies to the flexure test method for steel wire reinforced hydraulic hoses and hose assemblies. GB/T 14904-1994 Flexure hydraulic impulse test for steel wire reinforced rubber and plastic hoses and hose assemblies GB/T14904-1994 Standard download decompression password: www.bzxz.net

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Rubber and plastics hose and hose assenmbHes-wirereinforced-Hydraulic impulse test with flexlngGB/T14904—94
This standard refers to the international standard ISO6802—1991 "Rubber, plastic hose and hose assemblies reinforced with flex-hydraulic impulse test".
1 Subject content and scope of application
This standard specifies the method for conducting a flexural hydraulic impulse test on a hose according to the test parameters specified in GB/T5568. This standard applies to the flexion test method of steel wire reinforced hydraulic hoses and hose assemblies. 2 Reference Standards
GB/T5568 Non-flexure hydraulic pulse test for rubber and plastic hoses and hose assemblies 3 Specimens
The specimen is a hose assembly, and the free length of the hose between the two joints is 1L. It should be calculated according to formula (1): L=4.14+3.57d
Where: R—minimum bending radius specified in the hose product standard, d—… hose outer diameter,
L—free length of the hose (deviation ±15mm), mm At least 4 specimens should be tested,
4 Test device and specimen installation bzxZ.net
The test device is a pulse test bench equipped with a flexure device. The specimen can be installed on the test bench and flexion movement can be performed as shown in the figure. The flexure device is equipped with a manifold mounted on a rotating arm and a fixed manifold. The center line of the fixed manifold is exactly the rotation center line of the rotating manifold. The rotating manifold is kept parallel to the fixed manifold, and the number of rotations per minute of the rotating manifold should be 34% to 38% of the number of pulses per minute. Therefore, the bending desire is proportional to the number of pulses.
The distance from the vertical center line of the fixed manifold to the rotation center is A. The hose is flexed with a radius less than the minimum bending radius and a radius greater than the minimum bending radius near the two end joints. The distance A. should be calculated according to formula (2): A = 1. 75R + d
Where: R——minimum bending radius:
d——hose outer diameter;
A--the distance from the vertical center line of the fixed manifold to the rotation center (deviation ± 2mm), mm, approved by the State Administration of Technical Supervision on January 2, 1994 (2)
Implementation on October 1, 1994
5 Test procedures
Body ring tube
Greater than the diameter of the small bend
1/2 of the small bend radius
GB/T 14904-94
Bending impulse test specimen installation diagram
Small radius
Greater than the minimum semi-circular
Test pressure inlet
Connect one end of the hose specimen to the manifold of the rotating arm of the test device, and the other end to the fixed manifold, and perform the pressure pulse test according to the method specified in GB/T5568.
Begin the test until the hose specimen is damaged or the number of cycles specified in the hose product standard is reached. If the damage occurs within 25mm of the joints at both ends, it should be considered as joint damage, and the specimen should be replaced and tested again if recorded truthfully.
6The results show
4 pulse cycles and bending times of the specimens. 7 Test report
The test report shall include the following contents:
Full description of the tested hose or hose assembly, number of this national standard;
Test temperature;
Test pressure,
Test liquid;
Rate of pressure rise;
Pulse cycle rate:
Flexion frequency,
Location and form of failure of each hose sample and all conditions of the test of each hose sample; Number of pulse cycles when each hose fails;
Test date.
This standard is proposed by the Ministry of Chemical Industry of the People's Republic of China and is made by the National Technical Committee for Standardization of Rubber and Beverage Products. This standard is made by the Ministry of Chemical Industry of the People's Republic of China and is made by the National Technical Committee for Standardization of Rubber and Beverage Products.
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