Carbon steel castings for welded structures (GB/T7659-1987)

Carbon Steel Casting for Welded Structure(GB/T7659-1987)

Carbon steel casting is a manufacturing process of producing metal structures and parts by pouring molten ferrous or nonferrous metal into a mold. This process is prevalent in the construction industry as it provides a faster and more cost-efficient method of production compared to standard steel fabrication. The metal is melted, poured and cooled until it solidifies into a desired shape.

Carbon steel casting is often used in the production of welded structures such as construction frames, bridges and load-bearing beams. GB/T7659-1987 outlines the conditions that must be met by carbon steel casting used for welded structures. Generally, the surface of the casting must be clean, free from slag or blowholes and have adequate strength for welding. Any weld beads present should not exceed 0.3mm. The grain of the carbon steel should be evenly distributed throughout the casting and adherence to surface requirements is insisted on. In addition, the carbon steel castings are to be normalized after casting so as to reduce the tendency for the metal to become brittle or distorted during the welding process.

The mechanical properties of the carbon steel castings should also meet certain requirements, with different grades from 1 to 8 depending on the application and structure. The tensile strength and elongation before fracture should be determined according to the required user grade, as should the impact energy and energy absorption, although the latter two are usually dependent on the design of the welded structure.

In conclusion, G59/T7659-1987 covers the requirements for carbon steel casting used in welded structures. This standard is applicable to all types of carbon steel and related specifications, including grey cast iron and nodular cast iron. It is important to note that while castings may meet the requirements of this standard, they should still undergo testing in order to ensure optimal performance, especially since welding conditions affect the mechanical properties of carbon steel castings.

GB/T7659-1987 carbon steel castings for welding structures Introduction

GB/T7659-1987 carbon steel castings for welding structures is a national standard put forward by the State Quality Supervision and Inspection Bureau of China. It is used as a basis for quality inspection of welding structures such as steel frame structures and hydraulic engines.

GB/T7659-1987 carbon steel castings for welding structures mainly includes the control of mechanical properties, chemical content, dimensional accuracy and surface quality of carbon steel castings for welding structures, as well as the rules for accepting or refusing, storing and using carbon steel castings for welding structures.

GB/T7659-1987 carbon steel castings for welding structures mainly stipulates that the carbon steel castings for welding structures must conform to the relevant technical requirements. The properties of the castings must meet the requirements of GB/T692, GB/T1178, GB/T5100, ASTM A788 and other standards. The chemical content must conform to the requirements of GB/T3131 and relevant parts of GB/T1178.

GB/T7659-1987 carbon steel castings for welding structures are widely used in the manufacture of railway transportation, general equipment, ships and other industries, and play an important role in the safety and quality of these products. Therefore, it is necessary to strictly select and manufacture carbon steel castings for welding structures in accordance with the requirements of the specification.