A Flexitank onion tank is a collapsible flexible tank, which when filled, is self-erecting. Flexitank Australia offer two types of onion tanks open top onion tanks with floating foam filed collars, and roll top enclosed lid onion tanks.
Flexitank now offers the largest range of onion tanks available anywhere in the world. With capacities ranging from 1000 litre (264 USG), to 120,000 litres (31,700 USG) - the BIGGEST onion tank in the world! - there is not a purpose or an application that our onion tanks do not suit. Our onion tanks are the perfect solution for a variety of temporary liquid storage requirements and can be manufactured from a variety of polymer fabrics to suit virtually any application.
Onion tanks are primarily designed for applications where rapid deployment is required with minimal set up time:
- Drinking water - emergency aid relief, potable mains water replacement
- Temporary liquid storage for repairs and maintenance of another liquid holding device (tanks, swimming pools, ponds)
- Temporary containment of almost any liquid (waste water clean-up, oil spill, chemical spills, decontamination)
- Spill containment and water filtering
- Frac tanks for hydraulic fracturing
- Bushfires & fire fighting, helicopter refills
- Rainwater harvesting
- Short term construction site liquid storage
- Military requirements
A key advantage of a Flexitank onion tank is the small amount of ground space consumed when full versus a pillow tank. As an example, a 40,000 litre onion tank will use approx. 35m2 of space. The same capacity pillow tank will need some 50m2 of space to get to capacity.
Available in capacities ranging from 1,000 litres to 120,000 litres (264 USG - 31700 USG), a Flexitank onion tank is delivered as a ready to use solution that is designed for any liquid containment application.
Flexitank onion tanks provide an array of advantages unique to this style of flexible tank:
- Very quick setup time – most Flexitank (Australia) onion tank sizes take 1 – 2 people between 5 and 10 minutes to setup;
- Easily transportable to remote and difficult to access locations;
- No frame or parts to assemble – simply unfold the tank and begin filling;
- Flexitank Australia’s unique heavy duty construction makes our range of onion tanks suitable for a large variety of unique and difficult applications;
- 100% self-supporting;
- Can handle ground inclines of up to 10 degrees;
- Easy to pack down and fold away – Flexitank Australia’s design incorporates a reinforced ground sheet which doubles as a carry bag;
- Open top tanks are supplied with cover to protect the liquid being held from dust and contaminants – very important with regards to drinking water applications;
- Closed top roll top onion tanks offer 100% contamination protection for the liquid being held as well as additional liquid security – a vital aspect when holding sensitive liquids;
- The nature and shape of a Flexitank Australia onion tank means they have the ability to fill and empty at a much faster rate than that of a pillow tank;
- By utilising a greater height than that of a pillow tank, and onion tank will typically use approx. 25% less ground space to achieve its desired capacity; and,
- Manufactured by Flexitank Australia to defence specifications using the latest welding technologies
Arrays of fittings are available to suit any application a Flexitank onion tank maybe required for.
Flexitank Australia have access to exclusive European fabrics sourced for reliability in flexible tank manufacturing. Fabrics suitable for almost any liquid, and in particular drinking and irrigation water, grey water, contaminated water and the like are readily available in a broad range of weights ranging from 740gsm – 1850gsm, which meet stringent international standards and meet Australian and USA military specifications. PVC’s and poly urethanes are available and are utilized based on the onion tank application at hand.
Every open top floating collar onion tank is supplied with a protective cover opening manufactured from the same fabric as that of the onion tank itself. Both the open top and closed top options are supplied with heavy duty reinforced welded webbing handles for easy positioning and relocation. Open top tanks are also supplied with a drying handle on the inside of the base of the onion tank so it can be hung to clean and dry.
Flexitank onion tanks are available in eighteen standard sizes:
|Capacity (litres)||Capacity (USG)||Bottom diametre (mm)||Top diametre (mm)||Tank height* (mm)|
For open top onion tanks, add 120mm to the height for the filled height of the onion tank including the floating foam collar.
Please note closed top onion tank are available in capacities from 1,000 - 15,000 litre options only.
All onion tank dimensions are listed as standard sizes with typical fabric selections. Size may vary depending on the type of fabric required for the described application.
Standard fittings supplied include:
(note a variety of fittings outside of these standard fittings can be supplied in 2” to 6” options)
- 1,000 – 18,000 litre (1,320 – 4,752 USG) onion tanks are supplied with 2 x 2” male camlock fittings with ball valves and dust caps;
- 20,000 – 25,000 litre (5,280 – 6,600 USG) onion tanks are supplied with 2 x 3” male camlock fittings with ball valves and dust caps;
- 30,000 – 40,000 litre (7,920 – 10,560 USG) onion tanks are supplied with 4 x 3” male camlock fittings with ball valves and dust caps;
- 50,000 litre + onion tanks are supplied with custom advised fittings, all with ball valves and dustcaps;
- ALL onion tanks are supplied with a reinforced 700gsm ground sheet 1 metre larger than the bottom diameter of the onion tank – this ground sheet also acts as a carry bag with camlock buckles and lifting handles
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