Tank containers: construction, types and applications

Main structural components

The central component is a vessel secured within a space frame. The frame transfers transport loads to the corner fittings and protects the vessel during normal handling operations.

Depending on the application, the unit may include insulation, an outer shell, access platforms, protective covers and specialised valves. The exact configuration is determined by the design and cargo category.

Why there are different types

Liquids, liquefied gases and cryogenic media impose different requirements on a tank. Some applications primarily require chemical compatibility and leak-tightness; others focus on pressure containment or minimising heat ingress.

A type designation is therefore more than a model name. It relates to the regulatory category and operating conditions of the specific transport unit.

Why a container frame is needed

A standardised frame ensures compatibility with container infrastructure: terminals, railway wagons, road chassis and container ships. Lifting, stacking, securing and transport loads pass through the frame structure and corner fittings.

GOST 31314.3-2006 treats a tank container as a transport unit whose vessel and frame must jointly withstand the specified service loads. Vessel strength therefore cannot be assessed separately from its attachment to the frame and the behaviour of the complete structure during handling.

What determines reliability?

Reliability depends on the condition of the vessel, frame, supports, valves, connections and protective elements. Insulated designs also require an intact insulation system without damage that could increase heat ingress.

Strength verification requirements include calculations and the tests prescribed by the standard. Following the 2020 amendment, GOST 31314.3 includes a separate longitudinal dynamic test simulating impact loads in railway operations. This highlights that transport suitability depends on the dynamic behaviour of the complete structure.

Periodic inspection and maintenance follow the manufacturer’s documentation and the rules applicable to the specific cargo and tank type. Successful type testing does not replace in-service inspection of each unit.

What GOST 31314.3-2006 confirms

GOST 31314.3-2006, harmonised with ISO 1496-3, establishes specifications and test methods for Series 1 tank containers. Its purpose is to confirm that the transport unit withstands loads arising during standard container operations and transport.

The standard covers the interaction of the frame, vessel and attachments. For the customer, matching ISO container dimensions alone does not establish transport suitability: the design must complete the specified strength verification programme.

• strength of the load-bearing frame and corner areas during container handling;
• performance of vessel-to-frame attachments under combined loads;
• resistance to longitudinal dynamic loads relevant to railway transport;
• suitability for the specific cargo category, assessed together with ADR/RID/UN transport rules.

Sespel’s industrial experience

Sespel’s range includes tank containers for different cargo groups, from chemicals to cryogenic media. In practice, differences in use affect not only the T designation, but also working pressure, capacity, valves and vessel design.

For example, the C11L26RS specification describes a 20-foot T11 tank container with a 26,000-litre capacity for liquids, while the C75D43RS is a 40-foot T75 with a 43,300-litre inner vessel designed for cryogenic temperatures. Both model specifications also list Russian Maritime Register of Shipping certification.

Developing the technical specification

To select the correct design, the manufacturer needs product properties, required capacity, temperature conditions, mass limits and logistics requirements. More precise input reduces the risk of a unit that fits dimensionally but is unsuitable for its intended use.

For specialised and dangerous goods, the solution must always be checked against current regulations. Type selection cannot be based solely on capacity or visual similarity.

Input required for regulatory compliance

The specification must cover more than capacity. Regulatory selection requires exact product identification, transport classification, density, operating and limiting temperatures, partial or saturation pressure, filling and discharge requirements, and seal and valve materials.

The logistics scheme must also be defined: rail, road, sea, climatic regions, permitted gross mass and infrastructure constraints. Together, these determine the vessel, frame, valves and mandatory tests.