S355JR coil is a common low-alloy high-strength structural steel widely used in construction, bridges, ships, vehicles, and other fields. Its common thickness specifications range from 5-350mm.

The thickness specifications of S355JR coil are determined based on its application and required material properties. Generally, in the construction field, the thickness of S355JR coil typically ranges between 6-100mm, while in fields such as bridges, ships, and vehicles, the thickness may be greater.

It is important to note that the thickness specifications of S355JR coil are not uniform; different specifications are suitable for different applications and purposes. Therefore, when selecting the thickness specifications of S355JR coil, it is necessary to choose based on specific usage requirements and design considerations.

Additionally, the mechanical properties and chemical composition of S355JR coil also vary depending on its thickness specifications. Generally, as thickness increases, the strength and hardness of S355JR coil gradually improve, while plasticity and toughness gradually decrease. Therefore, when selecting the thickness specifications of S355JR coil, the requirements for its mechanical properties and chemical composition must also be considered.

In summary, the common thickness specifications of S355JR coil are 5-350mm, but the specific thickness specifications need to be determined based on the application and required material properties. At the same time, the requirements for its mechanical properties and chemical composition must also be taken into account.