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Low-alloy steel plates are commonly used in low-temperature pressure vessels to meet their service requirements. GB 3531–83 defines the requirements of low-alloy steel plates for such vessels.
The standard specifies the composition, properties and delivery requirements of the low-alloy steel plates used in the manufacture of low-temperature pressure vessels. The steel grades covered in this standard (grades 16MnDR, 09MnNiDR, 15MnNiDR, etc.) are intended for use in the manufacture of vessels designed for low-temperature service.
The material supplied according to the standard must be subjected to normalizing, quenching and tempering, or normalized and tempered treatment. The maximum thickness of such materials should not exceed 40 mm. The properties of components of low-alloy steel plates grade 16MnDR are given in the chemical composition section. The mechanical properties specified for these plates are tensile strength, yield strength and elongation. These mechanical properties must meet the specified requirements for various grades in the standard.
Delivery lengths of the plates should preferably be as long as possible and should not be shorter than 2000 mm. The end of the plates should be square and even, without burrs. The surfaces of the plates should be flat, without ridges or unevenness. The standard also specifies defects on the plate surface, such as rust, cracks, surface defects, etc., that are not allowed. The manufacturer should also provide test certificates to confirm the conformance of the plates to the standard requirements.
In conclusion, GB3531–83 is an important standard covering the requirements of low-alloy steel plates used in low-temperature pressure vessels. It defines the requirements of the compositions, properties, delivery lengths and other technical requirements of the steel plates. The material supplied according to the standard must be subjected to normalizing, quenching and tempering, or normalized and tempered treatment and compliance with all the requirements of the standard assures good quality of the plates for use in low-temperature pressure vessels.
