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Buoyancy and Salvage Lift Bags

Fuel and Gas Storage Bladder

Weather & Warehouse Curtains

Tanks for Rainwater Collection

Aquaculture Liners

Inflatable Brattice Walls

Custom Industrial Tank Liners

Dam and Pond Liners

Potable Water and Liquid Storage

Inflatable Underwater lift bags

Load Testing Bags

Thermal Concrete Curing blankets

Energy Storage and Production

Grain Bunker Covers

Buoyancy and Salvage Lift Bags

Fuel and Gas Storage Bladder

Weather & Warehouse Curtains

Tanks for Rainwater Collection

Aquaculture Liners

Inflatable Brattice Walls

Custom Industrial Tank Liners

Dam and Pond Liners

Potable Water and Liquid Storage

Inflatable Underwater lift bags

Load Testing Bags

Thermal Concrete Curing blankets

Energy Storage and Production







Fleximake onion tanks are frameless, self-supporting “Onion” shaped tanks that are used for storage of water and other types of liquids. Onion tanks, also known as collar tanks, collar dams, onion bladder tanks and collapsible tanks, are ideal for liquid storage applications that require deployment of tanks in a very short time. Typically, Fleximake onion tanks can be set up by one or two people and be ready for filling in about 10 to 15 minutes.
Our tanks are fitted with innovative, circular, self-raising and floating collar, which is made of closed cell foam, for easy filling. This makes Fleximake onion tanks the ideal choice for firefighting, drinking water storage for disaster relief, military operations, spill containment, pool repairs and other situations in need of short term storage. These collapsible reservoirs can be emptied and folded neatly for storage and transportation. Fleximake onion tanks are designed to be tough and made with heavy duty fabrics for on-going use and for longevity.
| Model No | Capacity(Litres) | Base Diameter D2 (mm) | Top Diameter D1 (mm) | Height H (mm) |
| FMOT002 _ _ _ _ | 2,000L | 1,900mm | 700mm | 1,000mm |
| FMOT003 _ _ _ _ | 3,000L | 2,300mm | 1,000mm | 1,000mm |
| FMOT005 _ _ _ _ | 5,000L | 2,800mm | 1,500mm | 1,000mm |
| FMOT007 _ _ _ _ | 7,000L | 3,200mm | 1,700mm | 1,100mm |
| FMOT010 _ _ _ _ | 10,000L | 3,700mm | 1,900mm | 1,250mm |
| FMOT015 _ _ _ _ | 15,000L | 4,400mm | 2,600mm | 1,250mm |
| FMOT020 _ _ _ _ | 20,000L | 5,000mm | 3,300mm | 1,250mm |
| FMOT025 _ _ _ _ | 25,000L | 5,500mm | 3,700mm | 1,250mm |
| FMOT030 _ _ _ _ | 30,000L | 6,000mm | 4,200mm | 1,250mm |
| FMOT035 _ _ _ _ | 35,000L | 6,400mm | 4,600mm | 1,250mm |
| FMOT050 _ _ _ _ | 50,000L | 7,500mm | 5,600mm | 1,250mm |
| FMOT070 _ _ _ _ | 70,000L | 8,800mm | 6,800mm | 1,250mm |
| FMOT090 _ _ _ _ | 90,000L | 9,900mm | 7,800mm | 1,250mm |
| FMOT100 _ _ _ _ | 100,000L | 10,500mm | 8,200mm | 1,250mm |
| FMOT130 _ _ _ _ | 130,000L | 12,000mm | 9,500mm | 1,250mm |
Note: _ _ _ _of the model number in the above table represents the code for the fabric material. These codes are shown in the table in “Fabric Material Choices for Onion Tanks” tab that details the fabric material selection. Example: Material code for RPVC 900gsm is P09N. Therefore, the model number for 30,000L onion tank made out of food grade RPVC 900gsm is FMOT030P09P

Please click here to download general arrangement drawing of our standard onion tank.
| Fabric Material | g/m2 (gsm) | Suitable applications | Data sheet and Fluid resistance guideline | Fabric Material Code |
| RPVC | 900 | Non-potable water, Certain chemicals, Certain oils | Download datasheet</ | P09N |
| RPVC | 900 | Food Grade, Potable water(i.e. drinking water) Comply with AS/NZ 4020 standard | Download datasheet</ | P09P |
| RPVC | 1100 | Non-potable water, Certain chemicals, Certain oils | Download datasheet</ | P11N |
| RPVC | 1100 | Food Grade, Potable water(i.e. drinking water) Comply with AS/NZ 4020 standard or equivalent international standards | Download datasheet</ | P11P |
| RPVC | 1400 | Non-potable water, Certain chemicals, Certain oils | Download datasheet</ | P14N |
| TPU | 960 | Potable water (i.e. drinking water) Comply with AS/NZ 4020 standard or equivalent international standards | Download datasheet</ | TPUP |
| TPU | 1230 | Fuels, Oils, Certain Chemicals | Download datasheet</ | TPUN |
| ER1000 | 1000 | Most chemicals, Certain oils | Download datasheet</ | ER10 |
If applicable fluid does not list in the above fluid resistance guideline datasheets or if the data is not clear to you, please contact us in order to select a suitable material for your onion tank.


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