Rubber Material Test
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Outer and inner rubber material requirements
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Test item
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Test method
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Required valuve
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Out rubber
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Inner rubber
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1. Before ageing
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1.1Tensile strength
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ISO 37:1994
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18 MPa or more
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10MPa or more
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1.2 Elongation
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ISO 37:1994
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400% or more
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400% or more
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1.3 Hardness
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ISO 7619:1997
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60 ±10
(Durometer hardness Type A)
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50 ±10
(Durometer hardness Type A)
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2. After ageing
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ISO 188:1998
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Air oven ageing, 70℃±1℃ 96h
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Air oven ageing, 70℃±1℃ 96h
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2.1Tensile strength
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ISO 37:1994
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Not less than 80% of the original property
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Not less than 80% of the original property
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2.2 Elongation
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ISO 37:1994
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Not less than 80% of the original property
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Not less than 80% of the original property
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2.3 Hardness
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ISO 7619:1997
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Not exceed original property more than 8
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Not exceed original property more than 8
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3. Tear
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ISO 34-1:1994
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400 N/cm or more
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No requirement
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4. Compression set
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ISO 815:1991
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30% (70℃±1℃ for 22h) or less
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No requirement
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5. Static ozone ageing test
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ISO 1431-1:1989
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No cracks after elongation by 20% and exposure to 50 pphma at 40℃ for 96 h
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No requirement
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apphm: Parts of ozen per hundred million of air by volume.
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For final products three important testaments are implemented.
Hydraulic Blasting Tests- Beyond Industrial Standards
There are two industrial standards for ship launching airbags
CB/T 3837-1998 Technological Requirements for ship Upgrading or Launching Relying on Airbags
(Issuer :Shipbuilding Industry Standard, PRC)
CB/T 3795-1996 / CB/T 3795-2009 Air bag for ship up to or down to launching way
(Issuer :Shipbuilding Industry Standard, PRC)
But people may find that the standards have the low demand of ship launching airbags considering nowadays the increasing launch demand. Eversafe Marine Engineering execute his own test and QC principles which mainly include the hydraulic blasting test and compression test.
Hydraulic blasting test is the ultimate test for the Ship Launching Airbags’ performance, material, manufacturing technique and structure type. Meanwhile, Hydraulic blasting test also can be used to confirm the safety working pressure.
Most reported hydraulic blasting tests are executed with airbag model not the regular airbags. As far as we know we are the only company who did this test with regular products.
Compression Test-Precise Technology
According to practical application of marine airbags we take two types measure methods which correspond to dynamic compression and static compression respectively. One method is compress inflated airbag to 30% of its initial diameter within two minutes and record every steps’ data by sensors. Another method is set airbag’s working height first and pump it to different pressures then change working heights and inflate again.
Air tightness Test
Airbags are placed in a constant temperature and humidity facility to test its air leakage ratio
