ISO tank containers or tanktainers as they are sometimes called are used for storage and/or transport of a range of chemicals, powders, foods, fuels, liquids, oils, gases and more.
Budget Shipping Containers now provides quality used ISO Tank Containers, all of which are professionally repaired, tested and calibrated by our experienced team of engineers.
There are many types of tank containers beside the standard tanktainers and these include electrically heated tanks, reefer tanks, lined tanks, baffled tanks to multi-compartment tanks and tanks suitable for gases. In this guide we aim to give you an idea of the types and ranges of tanks that are available and their common applications.
We source all our tanks direct from professional container tank companies and if they insist that the container isn’t to be used for shipping purposes, we can remove data plates and company logos from the tanks.
Typically, tank containers consist of a stainless steel vessel that is then surrounded by a layer of insulation, either Rockwool or glass wool, and (typically) a protective layer of Glass Reinforced Plastic (GPR) and an outer layer of either stainless steel or aluminium with the whole thing then being mounted in a steel frame. Its important to mention that the exact construction of one tank to the next can vary – often as they are designed and built for very specific uses.
These ISO container tanks have the same dimensions as a GP or general-purpose shipping container conforming to ISO 688, so they are 8ft wide and 8’ 6’’ in height and come in lengths of 10’, 20’, 30’’ 40’ and 45’. (Most commonly available in 20ft options) ISO tanks have different designs dependent on their usage and range from 9,000 to 27,00 litres in capacity.
In terms of structure, there are three structural types of tanktainer including:
Frame tank – the barrel load is supported in a structural frame and the barrel does not provide any strength to the container.
Beam tank – here, the barrel is supported by the end frames of the container and, in this case, the barrel is integral in the strength of the overall structure.
Collar tank – In this design, the barrel is supported by the end frames with a collar type SLL welded to the barrel end dome and the end frames.
In essence, the stronger the frame type, the heavier the tare weight of the tank, meaning a reduced product payload and if you have a container with top rails, the payload is further reduced. A Stronger container may allow you more or different handling options (for example being able to lift from the top corner castings) so for many tank enquiries we will have a quite detailed set of questions about how you intend to load and use your tank to ensure we get the right kit to fit your needs.
Heated containers utilise either steam or electrical heating systems with the system heating or cooling the products being transported by means of temperature transfer mediates including water, steam or electrical thermal elements. Heating is used to increase or decrease the fluidity of the product for easier loading and unloading. In all instances, the heating systems is enclosed by insulation and cladding.
Design and Safety Features of ISO Tank Containers
The tank shell is typically produced using either stainless steel or carbon steel with the shell thickness and pressure rating of the vessel being determined by the regulatory codes applied to it. In the cases of the T1 to T23 ISO tanks, the shell thickness will be between 3 to 10mm and the shell vessel must pass a minimum test pressure dependent on the tanks ‘T’ code. With the minimum test pressure being 1.5 times the Maximum Allowable Working Pressure.
For container inspection purposes, there is an opening on top of the unit (manhole) that is 500mm or larger in diameter and this is normally located in the manlid spill box. To ensure a good seal, the manlid is fitted with a gasket of either rubber or PTFE and where a ‘gas tight’ seal is required, the gasket will be made of an outer layer of PTFE that covers a nitrile rubber core.
To prevent an explosion caused by excess pressure, and vacuum-relief, the tank is fitted with a Pressure Relief Valve.
Bursting or frangible discs provide protection to the pressure relief valve from damage that may otherwise be caused by the effects of corrosive liquids.
Usually located in the rear spill box is the airline or vapour valve that is used to balance pressure between the inside and outside of the container and it could be used as a connection for a pressure discharge. This valve can also be used as a vapour return line in a ‘closed loop’ filling or discharge system to prevent fumes escaping in to the atmosphere.
The top discharge valve and siphon tube are typically located in the rear spill box and this can be used for top loading and unloading of cargo and the siphon tube is used top unloading of all cargo and the top loading of any highly flammable liquid.
The central and rear spill boxes are located on the top of the ISO container and they are there to retain any spills that may occur and are usually accessed by moving along the walkway on top of the tank. The walkway is produced from perforated aluminium plate and can only support two people.
The bottom discharge valve can be found to the rear of the tank and with the exception of the T1, t3 and T6 tank, all ISO tanks that are allowed to have a bottom discharge valve must have three serially mounted and mutually independent shut off devices that are fitted with the bottom valve assembly. These are typically a 3’’ internal valve or foot valve then a secondary valve, typically a 3’’ butterfly valve followed by the third shut-off device a 3’’ BSP threaded cap. The foot valve is located within the tank and is designed to remain intact even when the main external parts of the valve have been damaged or impacted on.
There will be at least one thermometer mounted to the cladding on the rear of the container for measuring the temperature of the external shell. For special cargo, the probe of the thermometer can extend in to the cargo via a thermowell.
Where flammable cargo is concerned, the unit must be earthed via the earthing point at the rear of the tank to a suitable grounding point.
The documentation box is usually mounted within the frame of the unit and can be used for holding Material Safety Data Sheets etc.
Also found on the rear of the tank is the containers data plate. This holds important data including:
Tank type and its serial number
Name of the owner
Name of manufacturer and the manufacturers serial number
Capacity, Tare weight, maximum permissible gross weight and the stacking weight
MAWP and test pressure
Regulatory approval information
Date of initial test, last and next 2.5 year and 5-year test
The data plate also contains the CSC safety approval data.
Types of ISO Tank Containers
There are various types of tanktainer including food-grade tanks which can only be loaded and used for food grade products. Then there’s the reefer or refrigerated tank that has the ability to cool products being transported through to the silo tank that’s used for the transport of grains and powders.
Other types of tank container include
The T1 ISO tank containers – used for wines and light liquids
The T4 ISO tank container – used for non-hazardous edible and no-edible oils
Through to the T75 ISO tank container that’s used for Cryogenic liquids
Lined tanks – used for the transport of either high purity of highly corrosive products
The above are just a few examples of what tanktainers are used for, and to give the reader an idea of the range of tanks that may be available in the marketplace. If you have any questions or require additional information about our range of ISO Tank Containers, please call or send an enquiry though our contact us page where you’ll find our contact form.