Water weight bags are simple and safe water filled crane test weights designed to provide proof load testing instead of traditional solid load test weights.
DOOWIN load test water weight bags are designed for proof load testing the lifting equipment and structures that request proof load weight testing. When it’s newly finished, or periodic check or maintenance. Such as crane load testing, beam load test, lifeboat davit load test, derrick load testing, overhead crane load test. So, this water-filled water weight bags offer one kind of innovative crane load test weights solution. Most noteworthy, it has the advantages of Safety, Economy, Convenience, High Efficiency.
The pillow type bladder tanks can be used to store many kinds of liquid. The main appplication include two industires: water and chemical liquid. These liquids included the following but not limited to:
Please refer to the right picture to know its construction.
The standard filling fitting is 2”, 3” and 4” high quality PP flange with cam-lock with one safety cap (refer below picture). The other material filling port and camlock are available upon request. We can do aluminum or stainless steel flange and cam-lock, with stainless steel or brass ball valves.
The standard filling fitting is 2”, 3” and 4” high quality PP flange with cam-lock with one safety cap (refer below picture). The other material filling port and camlock are available upon request. We can do aluminum or stainless steel flange and cam-lock, with stainless steel or brass ball valves.
Ground sheet can protect your pillow tanks. It will be supplied upon request.
Please refer to the following general drawing for the small, middle and large pillow type bladder tanks. We also make the customized design upon request.


Fill/Discharge Valve (2” or 3”) ———— Drain Valve (2” or 3”) ————— Air Bleed
DOOWIN pillow-type bladder tanks are from 200L to 800,000L. The following sheet is the standard specification.
Customized size and shape are available upon request. If you have any special request, please contact us now.
Grade | Model | Capacity (L) | Capacity (Gal.) | Length (m) | Width (m) | Filled Height (m) | Length (inch) | Width (inch) | Filled Height (inch) |
|---|---|---|---|---|---|---|---|---|---|
UTILITY PILLOW TANKS | PT-1T | 1,000 KG | |||||||
PLB-2T | 2,000 KG | ||||||||
PLB-3T | 3,000 KG | ||||||||
INTERMEDIATE PILLOW TANKS | PT-5 | 5,000 KG | 3 | ||||||
PLB-6T | 6,000 KG | ||||||||
PLB-8T | 8,000 KG | ||||||||
PLB-10T | 10,000 KG | ||||||||
PLB-12.5T | 12,500 KG | ||||||||
PLB-15T | 15,000 KG | ||||||||
PLB-20T | 20,000 KG | ||||||||
PLB-25T | 25,000 KG | ||||||||
PLB-30T | 30,000 KG | ||||||||
PLB-35T | 35,000 KG | ||||||||
PLB-40T | 40,000 KG | ||||||||
PLB-50T | 50,000 KG | ||||||||
BULK PILLOW THANKS | PT-60 | 55,000 KG | |||||||
PLB-75T | 75,000 KG | ||||||||
PLB-100T | 100,000 KG | ||||||||
PLB-110T | 110,000 KG |
Our waterweights bags are designed manufactured, tested, and certificated in 100% compliance with LEEA 051 guidelines.
DOOWIN load test proof load bags are manufactured with the highest quality PVC coating fabric material SGS certificated. Our crane test water bags are manufactured and tested to comply with the LEEA 051 Guidance. In addition, we can provide BV, ABS, and LR third-party certificates upon request.

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We did the drop test in TUV/NEL UK for the water weight bags 5t, 15t, 25t.
We can provide test certificates from third-party testing agencies such as CCS, BV, SGS, ABS, apave, etc.
Our raw material are tested and certficated by SGS.
Discover more load testing projects, visit doowinloadtesting.com





DOOWIN is committed to providing high quality proof-load testing water weight bags and air lifting bags for our customers worldwide.








We offer specially designed sausage-type water-filled proof load bags to do the Static and dynamic testing for the lifeboats and davits
Our load-measuring products include portable tension load links and load-measuring shackles both in wireless monitor.
We offer specially designed elongated sausage type water-filled proof load bags to test gangways.
Pillow-type water tanks can be used to verify the structural integrity of buildings, bridges, elevators, loading ramps, gangways, accommodation, ladders, and decks.
DOOWIN maintains an extensive inventory of proof-load testing equipment, such as water-weight bags, load cell/Dynamometers, wire ropes, round slings, pumps, and water hoses. Our engineers and workers are very experienced with load testing.