It mainly includes appearance quality, internal quality use quality. Appearance quality refers to the surface roughness, surface defect, size deviation, shape deviation weight deviation of the casting; internal quality mainly refers to the chemical composition, physical properties, mechanical properties, metallographic structure of the casting, as well as the holes, cracks, inclusions, segregation other conditions existing in the casting; service quality refers to the working durability of the casting under different conditions, including wear resistance corrosion resistance , cold heat shock resistance, fatigue, shock absorption other properties, as well as cutting, weldability other technological properties.

The quality of cylinder accessories factory has a great influence on the performance of mechanical products. For example, the wear resistance dimensional stability of machine tool castings directly affect the precision maintenance life of machine tools; the size of impellers, casings inner cavities of hydraulic components of various pumps, the accuracy surface roughness of molding lines, directly affect the working efficiency, energy consumption cavitation development of pumps hydraulic systems; the casting of cylinder block, cylinder head, cylinder sleeve, piston ring exhaust pipe of internal combustion engines The strength heat resistance of the engine directly affect the working life of the engine.

There are many factors that affect the quality of castings. The first is the design process of castings. In order to avoid reduce the component segregation, deformation opening of the castings, it is necessary to consider the rationality of the design the aspects of carbon steel casting price, casting alloy casting process characteristics, i.e. obvious size effect, solidification, shrinkage stress, in addition to determining the geometry size of the castings according to the working conditions metal material properties Crack other defects. The second is to have a reasonable casting process. According to the structure, weight size of the casting, the characteristics of the casting alloy the production conditions, the proper parting surface, molding core making methods are selected, the casting reinforcement, chill, riser pouring system are reasonably set. To ensure the quality of castings. The third is the quality of raw materials for casting. The quality of metal furnace burden, refractory material, fuel, flux, modifier, casting sand, molding sand binder, coating other materials are up to standard, which will cause defects such as porosity, pinhole, slag inclusion, sand sticking, etc. in the casting, which will affect the appearance quality internal quality of the casting. In serious cases, the casting will be scrapped. The fourth is process operation. It is necessary to formulate reasonable process operation procedures, improve the technical level of workers, make the process procedures correctly implemented. The fourth is the price of the three-way pipe lost foam ductile iron casting.

In the quotation of three-way pipeline EPC ductile iron castings, the quality of castings should be controlled inspected. First of all, it is necessary to formulate process rules technical conditions raw materials, auxiliary materials to control inspection of each specific product. Each process shall be controlled inspected in strict accordance with the process rules technical conditions. Quality inspection of finished castings. It is necessary to equip reasonable testing methods appropriate testing personnel. Generally, for the appearance quality of the casting, the surface roughness of the casting can be judged by comparing the sample blocks; the surface micro cracks can be inspected by coloring method magnetic particle method. The internal quality of castings can be checked judged by audio frequency, ultrasonic, eddy current, X-ray y-ray.

The defects of sand casting are: cold shut, insufficient pouring, air hole, sand sticking, sand inclusion, sand hole, expanding sand, etc.

The liquid metal will stop flowing before the cavity is filled, which will cause the casting to have insufficient pouring cold insulation defects. When the casting is poured enough, the complete shape of the casting will be obtained; in cold shut, although the complete shape of the casting can be obtained, the mechanical properties of the casting will be seriously damaged due to the incomplete fusion joints.