A flexitank is a large, single-use bag made of layers of polyethylene, often with an outer woven layer, fitted inside a standard 20-foot dry container. It turns the container into a bulk liquid tank for one trip.
Flexitanks are for non-hazardous liquids only. They cannot be used for dangerous goods under the IMDG Code, so any product with a UN number needs an ISO tank, drums or IBCs instead.
Which products suit a flexitank
- Castor oil and many castor derivatives in liquid form, which Gujarat exports in volume.
- Glycerine and other non-hazardous polyols.
- Vegetable oils and some food-grade liquids, using food-grade bags and clean containers.
- Lubricating base oils and some plasticisers that are not classified as dangerous.
- Some non-hazardous surfactant solutions and latex grades, subject to the line's approval.
Why buyers use them
A flexitank carries more liquid than the same container filled with drums, because there is no wasted space between packages. Capacities commonly run up to around 24,000 litres, depending on the bag and the product's density. Filling and discharge are fast, and there are no drums to return or dispose of.
The trade-off is that the bag is used once and cannot be cleaned and reused. Your site also needs a way to discharge it, usually a pump and a hose connection, and somewhere to put the product straight away.
Risks to manage
- Leaks and bursts can contaminate the container, damage other cargo and cause clean-up costs. Most incidents trace back to poor fitting, a damaged container or a bag overfilled for the product's weight.
- The container must be in good condition, with no sharp edges, and fitted with a strong bulkhead at the doors.
- Many shipping lines accept flexitanks only from approved manufacturers and fitters, and some restrict them on certain routes.
- Viscous products may need a heating pad under the bag for discharge in cold climates.
- Food-grade products need bags and fitting practices that meet food contact rules in your market.
Checks before you choose one
First, confirm the product is not dangerous goods. Section 14 of the SDS should say not regulated, and the carrier will often ask for a non-DG certificate. Then check compatibility of the product with the bag material, and the maximum fill for the product's density.
Agree in the contract who supplies and fits the flexitank, who inspects the container, and who is liable for leaks. Ask for photos of the empty container, the fitted bag and the sealed doors. If the product is DG or needs a reusable tank, compare with ISO tank shipping.
Next step
The shipper and the flexitank fitter are responsible for a safe installation, and the line has the final say on acceptance. We check the container, fitting and sealing at loading. To start, book a free sourcing review.