We were told ship launching airbags can be used for many times with 5-8 years lifespan. But what is the criteria to judge one launching bag good or not good for using, when that bags may be 3 or 5 years old and got scars after several time using.
And how can we achieve the longer lifespan of ship launching airbags by own efforts?
Three core factors to judge old launching bags: working pressure, air tightness and surface condition according to ISO 14409.
- Working Pressure Test
If the old bag has been maintained and repaired well, inflate its pressure to be 1.5 times of rate pressure and keep the pressure for one hour. If airbags pass the test, then they can be used with rate pressure.
If the old bag has not been maintained and repaired well, inflate its pressure to be rate pressure and keep the pressure for one hour. If airbags pass the test, then they can be used with 70% of rate pressure.
Then, check below items and take subsequent operation accordingly.
| Bumps on airbag body | Failed | Cut bumps then patch |
| Cracks extend | Failed | Depends on quanity and degree, the decide repair or not |
| Patches swell | Failed | Remove patch and patch again |
- Air tightness
If old airbags have slight air leakage, test the airleakage ratio at working pressure. One hour 10% pressure drop is acceptable.
If old airbags have serious air leakage that can be heard, identify the leakage area first. Judge the airleakage reason, if it is caused be damage then repair them first. If two much leakage points, then give up that bag.
- Surface Condition Check
The purpose of surface checks is to decide the aging degree of ship launching airbags. Ship launching airbags are made of rubber, aging is unavoidable.
- Pinch or press airbag to test the elasticity. Too much aged airbags lose elasticity.
- And tiny cracks on ship launching airbags surface is another character of aging.
- Too much aged airbags may expose nylon cord on surface.
Aged airbag surface
How to achieve long lifespan of ship launching airbags
Three points: proper use, maintenance and storage
Lifespan of airbags can be 5-8 years. Anyway, it depends on how frequently airbags were used and how they are maintained, stored.
- Proper Use
Most of airbags damages are cut, puncture that can be avoided.
Even Evergreen ship launching airbags are most durable one in the world, they are made of rubber anywy, can be cut by steel, concrete, stones.
Just like car driving, you can not expect tires will always be safe when you get through throny roads. Take care for airbags just like your vehicle tires, protect them if have to let airbags contact or roll over sharp concrte, stones and steels.
Use airbags within their rate pressure. Evergreen ship launching airbags have 5-time safety factor that means airbags can be used with a higher pressure than rate pressure. But keep in mind, don’t use airbags with high pressure for long time, such as more than 10 hours.
Low pressure is good for airbag safety. If you have to roll airbags over an uncertain area which may have sharp stones or steel, low down airbag pressure can surely low down the airbag damage ratio.
- Good maintenance
Airbags are repaired in time when they get damage.
Airbags are cleaned when they come out from sea water
- Good Storage
Airbags are made of rubber; aging is the main problem besides damage. Storage condition should be:
Stored in cool, sheltered place, no direct sunshine
If airbags will be stored for more than 6 months, they should have talcum powder sprayed inside
Away from chemical, oil, organic solvents.
Palm oil on hardwares of airbag
Bad storage shorten air bags’ lifespan
