Cast iron manhole cover is not the heavier the better the quality, its two main parameters are hardness and toughness. In general, the higher the hardness, the better the quality, but the hardness is higher and the toughness is better. This is a good cover. When designing, in addition to determining the geometric shape and size of the cast iron well cover according to the working conditions and the properties of the metal material, the rationality of the design must be considered from the perspective of the casting alloy and the casting process characteristics. What are the factors affecting the quality of cast iron manhole covers?

1. Technical planning of cast iron manhole covers. When planning, in addition to determining the working conditions and properties of the metal materials, the shape and size of the cast iron covers, but also from the point of view of the forging alloy and forging technical characteristics to consider the rationality of the plan, that is, a significant scale effect And coagulation, shortening, stress and other questions to prevent or reduce the occurrence of segregation, deformation, cracking and other defects in the composition of cast iron manhole cover.

2. Reasonable forging technology is required, that is, according to the construction of cast iron manhole cover, the size and size of the cast iron, the characteristics of the forged alloy and the production conditions, the appropriate type and appearance, the core making method, and the reasonable setting of forging ribs, cold iron, riser And pouring system, etc., to ensure the quality of cast iron manhole covers.

3, is the quality of raw materials for forging. Ductile iron manhole covers are used as shaft parts, such as crankshafts and connecting rods of diesel engines, which require high strength and require a combination of mechanical properties with good resistance. The cast iron manhole covers are quenched and tempered.