Shipping | What Is a Flat Rack Container? Types, Sizes and Uses?

Shipping | What Is a Flat Rack Container? Types, Sizes and Uses?

Nowadays, Flat Rack is widely used in international shipping. This article will explain you what Flat Rack is and when to choose to use it.



What Is a Flat Rack Container?
Flat Rack, abbreviation 20FR, a flat rack is usually for the transportation or storage of cargo with unique dimensions. Flat racks only have sides on the short side of the container, the bulkheads, so the cargo can stick out the side of the container during transportation.

Flat racks most commonly come in 2 sizes: 20 feet and 40 feet. The choice depends on the size of the cargo. Usually the dimensions of these two types only differ in length. The width and height are often similar. More information about flat rack dimensions can be found on our website.

But they’re designed to carry heavier and more concentrated loads than standard containers. Up to 2,000kg for the 20ft variety and 4,000kg for 40ft.



Flat Rack Container Dimensions

Picture is from the Web

Types Of Flat Rack Shipping Containers
Besides the different sizes, you also get two types of flat rack container: Collapsible and Non-collapsible. Let’s take a look at the difference between the two now.

Picture is from the Web

Non-collapsible flat rack
Non-collapsible flat rack containers have fixed walls on their shorter ends. This makes them more structurally sound than collapsible flat racks. The only disadvantage of non-collapsible flat racks is that they take up a lot of space when not in use.
It’s time to weigh up the options and decide if collapsible or non-collapsible work best for your needs.

Collapsible flat rack
A collapsible flat rack has sides that can be collapsed so the empty container can be shipped more efficiently. 4 collapsible flat racks would take the same amount of space as 1 regular dry van container!



What Cargo Can Be Shipped In a Flat Rack Container?
As you know by now, flat racks can carry various types of cargo that standard containers cannot. From agricultural produce like sugarcane and grain to windmills, flat rack containers can transport them all, especially industrial goods. Let’s have a look at some of the most commonly shipped cargo:

Breakbulk goods Heavy machinery Transformers Boilers Tanks Construction equipment Cranes Pipes and tubes Turbines Automobiles Steel Glass

No matter what cargo you’re planning to ship, it’s important that it’s loaded properly so that there’s no pressure placed on the goods themselves. For this reason, it’s better to store your flat racks either at the top of the container stack or on the ground. This prevents accidental damage due to contact with other cargo or containers.

Now, you must be wondering: If three sides of the container are open, how does the cargo remain secure?

Flat racks come with lashing rings on the side rails, floor and corners. You can keep your goods in place by cross lashing or loop lashing them. Some containers even come with lashing winches, latching belts and stanchions to provide additional support and security for your cargo.



How Cargoes Should Be Binded On Flat Racks?
Due to the nature of oversized or overweight shipments, there are certain guidelines imposed by shipping lines under SOLAS (Convention of Safety of Life at Seas) regulations.
These guidelines stipulate how cargoes should be handled, secured, and stowed on flat racks prior to loading on any vessel for an overseas voyage in order to ensure safety.



A summary of these guidelines are listed as follows:

Stuffing: Cargo should be positioned on the flat-rack to ensure suitable weight distribution, both along length and width so that the main area of gravity is not too far “off-center.” Over-width cargo and respective blocking and bracing materials should not be stowed within 30 cm (12“) of the corner posts of a flat-rack as this prevents the flat-racks from being loaded under deck.

Welding: Any kind of welding, drilling holes, or the modifying of a flat-rack’s structure is strictly prohibited.

Weight distribution: As explained above, flat-racks are designed to carry heavier, more concentrated loads than standard equipment. The main strength of a flat-rack lies in the two bottom rails; therefore cargo must either rest on these rails or have weight transferred to the rails by cross timbers. Although a maximum payload is marked on each flat-rack, the maximum weight the unit can carry is also dependent on the length of the cargo resting on the rails. The maximum payload can only be utilized when the cargo is spread over the entire length of the flat-rack’s bottom rails. Only half of the payload is permitted for short cargo (i.e. resting on about 1m of length only.) Specific requirements and limitations may vary depending on the carrier.

Bedding: Any bedding must be laid out across the flat-rack and needs to reach the main girders. Heavy weights are not allowed to be solely placed on the wooden floor of the flat-rack. Cargo is to be positioned on the flat-rack with its center of gravity in the middle of the flat-rack, lengthwise and across.

Anti-slip material: Any contact of metal to metal should be avoided. Wood dunnage or similar anti-slip materials, such as rubber, should be placed between cargo surfaces that are made of metal material and the flat-rack bottom rails. Using anti-slip material with high friction decreases the number of lashings required.

Lashing: In general, all cargo must be secured by using materials which are suitable for the size, construction and weight of the load.
The following points should be observed at all times:
`Web lashings require edge protection on sharp corners.
`Different lashing materials, such as wires and web lashings, should be not mixed on the same cargo, at least for securing purposes in same lashing direction. Different materials have different elasticity and create unequal lashing forces.
`Turnbuckles and shackles should be secured, so that they do not spin open during the voyage.
`Manufacturer’s guidelines and limitations must be obeyed at all times.

Securing in length direction: Securing cargo in length direction can be achieved by blocking and bracing with timbers or by a lashing system. Timber bracing is more common when cargo is crated; the heavier the cargo, the stronger the bracing needs to be. (That’s why we ask our clients in many cases to identify if the cargo is packaged in some way so that we can determine the correct type and way of cargo lashing/securement on flat racks.) Blocking should be braced against corner posts. Unpacked cargoes with suitable lashing points can be secured in length direction more effectively with direct lashings and in such cases no further bracing is necessary.

Securing in transverse direction: For securing against transverse and tipping forces, the best recommended lashing method is securing with cross lashings. This requires lashing eyes on the cargo for direct lashing systems. The preferred lashing method for cargo without lashing eyes is the (half) loop lashing, also called “Clashing System”. Every lashing must be installed in pairs, with one half of the pair starting and returning to the same side. The other half of the pair starts and returns from the opposite side. As mentioned, lashing material manufacturer’s guidelines on safe work load limits must be followed at all times. Friction, or “over the top” lashings are not recommended as this system does not prevent transverse motion; they are however acceptable especially for extra-wide cases.



Conclusion
We, ShiWen Construction Machinery Co., are not only a supplier of used construction machinery, we also provide transportation services.
If you need, please feel free to contact us!