Flexitank vs. ISO Quality and Why We Ship in Bulk?

Posted by: miamiseo
Category: Flexitanks
Flexitank vs Iso Tank

There are two principal methods available for the bulk shipping of liquids. The two most accepted industry-wide formats are through the use of flexitanks and ISO tanks. Bulk shipping is a standard format in industries like the petroleum and food industries. There are many advantages including economies of scale associated with the bulk transportation of liquids.

Petroleum products are traditionally transported across seas and land through pipelines or specially-designed tankers. Other Industries that deal in liquids such as edible oils and wine had lagged behind in considering bulk liquid transportation as a more viable option compared to smaller containers like barrels.


A flexitank is a bulk liquid storage container whose walls consist of multiple layers of polyethylene. The inner walls are made of flexible polyethylene while the outer wall is made of a stronger interwoven material called polypropylene.

loaded flexitank techno group

Flexitanks are the latest iteration in the development of bulk liquid storage containers for non-hazardous liquids.

Because the wall of a flexitank is flexible, it stands to reason that it requires an external structure to support it when it has been filled up with a liquid. The designers of the flexitank wisely saw that they could leverage the existing standard shipping containers to provide the solid wall that a filled up flexitank would need in order to sustain its weight.

By leveraging already existing standard shipping containers, flexitanks are providing a safer, healthier, and more cost-effective alternative to customized shipping tankers for bulk liquid transportation.

Flexitanks are used for shipping edible oils, food-grade liquid, wines, and other non-hazardous liquid chemicals via either road, rail, or marine transport. The capacity of a flexitank ranges from 12,000 to 26,000 liters or 3,170 to 6,900 gallons 

ISO Tank

The ISO tank is a shipping container that derives its name from the ISO standard. These tanks are designed for bulk transportation of hazardous and non-hazardous liquids.

A key distinguishing feature of an ISO tank from a flexitank is that an ISO tank is made of stainless steel. The inner wall of the tank is lined with various protective layers to prevent corrosion of the steel and also contamination of the liquid by reacting with the steel.

Advantages of an ISO Tank

It has a frame made of stainless steel making it very strong and able to withstand extreme pressure and damage.

These tanks are highly unlikely to leak the product they’re transporting because of the strength of the container itself.

An ISO tank does not require additional packaging material compared to a flexitank which needs to be stored in a standard shipping container when full.

ISO tanks can be used in the transportation of both hazardous and non-hazardous liquids while flexitanks can only be used to transport and non hazardous liquids.

Advantages of flexitanks

Great availability

Flexitanks are available for use without the need to clean and ship them to where they are needed. ISO tanks, on the other hand, have to be cleaned to avoid cross-contamination between different consignments of liquid. The process of cleaning and shipping the container to the point where it is required reduces the availability of the container and increases delays in transportation.

Special equipment not required

The process of loading and unloading liquids from a flexitank only requires a pump or a compressor and a suction hose. ISO tanks require expensive and heavy-duty machinery like cranes to load and offload the tanks from the transporting trailers.

Increased shipping capacity

Flexitanks have an increased liquid capacity of up to 24,000 liters while being held in a standard shipping container which translates to more than 50% more transportation capacity the liquids transported in bottled consignments and around 40% increase in shipping capacity than liquids transported in drum consignments.

For the businessman, this translates to a more efficient way of transporting more cargo and reduces the capacity required for transportation which leads to higher margins in the business.

Lower cost of transportation than other bulk transportation mechanisms

Other forms of bulk liquid transportation like ISO tanks come with external costs like the cost of cleaning up the container between shipments to prevent cross-contamination and the cost of acquiring the ISO tank which is more expensive than the purchase of a flexitank. We can also incur rental costs if the business only requires the ISO tank for one-time usage. We also need specialized equipment for moving as water is a requirement that is not necessary while using flexitanks.

Disadvantages of flexitanks

Damage to the container

The liquid contained in a flexitank will exert massive pressure on the walls of the shipping container and lead to the formation and bulging of the container leading to loss of the container if it is permanently damaged.

Potential leakage

The material from which the flexitank is made from, polypropylene is pliable and can be punctured during the transportation process leading to rupture of the wall and leakage of the full contents of the flexitank. This will lead to loss of the cargo and the additional expense of cleaning of the spillage.

Other benefits of bulk liquid transportation with flexitanks

An improvement in the bottom line

Bulk liquid transportation provides the benefits of the economies of large scale operation. Transportation of liquids in smaller containers like drums leads to exponentially higher costs because of the handling costs of smaller units which increases as the number of units increases. For example, the movement of drums from one point to another will require more labor hours and specialized equipment. This is an expense can be avoided if the entire consignment is held in a large container like a flexitank.

Optimal inventory management

The use of flexitanks eliminates the need for intermediate storage while awaiting the availability of a suitable transportation mechanism because flexitanks are readily available. The reduced handling that comes with using flex turns over as hotels or drums also leads to improved productivity and worker safety particularly in dangerous operations like off-loading and loading of the drums or bottles.

Improved Warehouse utilization

Because flexitanks can be safely held in standard shipping containers it leverages existing Warehouse space and does not require additional space which would come at great expense to the business.

Talk to Techno Group USA today and we’ll help you to streamline your bulk liquid transportation projects.

Author: miamiseo