Cast iron castings

Cast iron castings made from molten iron are collectively referred to as cast iron parts. Due to various factors, defects such as porosity, pinholes, slag inclusions, cracks, and pits often occur.

Including appearance quality, internal quality, and usage quality. Appearance quality refers to the surface roughness, surface defects, dimensional deviation, shape deviation, and weight deviation of castings; Mainly refers to the metallographic structure of castings, as well as the presence of holes, cracks, inclusions, segregation, and other conditions inside castings; The quality of use refers to the working ability of cast iron parts under different conditions, including resistance to cold and heat, fatigue, shock absorption and other properties, as well as machinability, weldability and other process properties.

Due to various factors, cast iron castings often have defects such as porosity, pinholes, slag inclusions, cracks, and pits. The commonly used repair equipment includes argon arc welding machine, resistance welding machine, cold welding machine, etc. For casting defects with low quality and appearance requirements, welding machines with high heat generation such as argon arc welding machines can be used to repair them.

The quality of cast iron parts has a significant impact on the performance of mechanical products. For example, the dimensional stability of machine tool castings directly affects the accuracy and lifespan of the machine tool; The accuracy and surface roughness of the impeller, housing, and hydraulic components of various pumps directly affect the working efficiency, energy consumption, and cavitation development of pumps and hydraulic systems; The strength and resistance to cold and heat of copper castings such as cylinder blocks, cylinder heads, cylinder liners, piston rings, and exhaust pipes in internal combustion engines directly affect the working life of the engine.

The surface area carbon and wrinkling of iron parts are two forms of surface defects in cast iron parts. During the casting process of cast iron, the solid and liquid products from the gasification and decomposition of the foam plastic model accumulated on the surface of the casting to form orange peel shaped carbon defects, as well as the surface wrinkling defects of the casting due to the poor filling temperature of the liquid metal.