A well-loaded, properly discharged flexitank is a seamless operation. Here's everything you need to know at each stage.
Getting the most out of a flexitank isn't complicated — but it does require the right preparation at both ends of the journey. A well-loaded, properly discharged flexitank is a seamless operation. Done carelessly, it's an expensive lesson.
The container is the first thing to check. It needs to be clean, dry, and structurally sound — no sharp protrusions, no residual moisture, and no previous cargo contamination. Even a small piece of debris on the container floor can compromise the flexitank during filling as pressure builds.
The bulkhead needs to be installed correctly before the flexitank is placed. Sun Flexitanks supplies a complete bulkhead kit with every order — steel support rods, P.P. corrugated cardboard, plastic roll, and cable ties — and the installation sequence matters. The bulkhead is what holds the flexitank in position during transit and prevents it from pressing against the container doors.
Flexitanks support three loading configurations: top load/top discharge, top load/bottom discharge, and bottom load/bottom discharge. The right choice depends on your pumping infrastructure at origin and destination — it's worth confirming both before the order is placed rather than discovering a mismatch on loading day.
Filling should be done at a controlled rate. Overfilling is one of the most avoidable causes of flexitank failure. Every Sun Flexitank has a rated maximum capacity — for standard units, that's 24,000 litres — and it should not be exceeded. As the tank fills, it will naturally settle and expand to fill the container floor.
Once filled, the valve is sealed and the container doors are closed. At this point, the cargo is secure and ready for transit.
For most cargo types, nothing needs to happen between loading and discharge. The flexitank is a passive container — it travels with the ship, holds its cargo, and arrives at destination ready to discharge.
For viscous cargoes with elevated pour points — palm oil, animal fats, tallow — if heater pads haven't been specified as part of the order, discharge can become extremely difficult or impossible in cooler climates. Specify heater pads at the time of order, not as an afterthought.
Discharge is typically faster and cleaner than drum or IBC discharge, particularly for high-viscosity cargo. With a bottom valve configuration, gravity does much of the work. With a top discharge setup, a pump is required — standard food-grade flexible hose and a compatible pump are all that's needed.
The flexitank should be fully discharged before the container doors are fully opened. After discharge, the flexitank is removed from the container, folded, and disposed of or recycled at destination. No cleaning, no inspection, no return logistics.
Sun Flexitanks has been supporting customers through loading and discharge operations for over 20 years, across trade lanes in the MENA region, India, South America, Africa, and Oceania. Full technical guidance is provided with every order, and our team is available to walk first-time users through the process. The learning curve is short — and once you've done it once, it becomes second nature.
Talk to the Sun Flexitanks team about the right solution for your cargo.