If the IP68 waterproof grade of castings is to be tested, the direct test method can be adopted for the air tightness tester equipment. The air tightness and waterproof test of castings must first customize a reasonable mold according to the shape characteristics of the castings to be tested. The mold must be able to well seal the interior of the product, and then the air tightness and waterproof test fixture of castings can be connected to the test port of the air tightness tester equipment, After the corresponding test parameters are set, the air tightness and waterproof test of castings can be started. The air tightness and waterproof test of castings can achieve rapid and accurate detection.
Due to the great process flexibility of machining, that is, a part can have many process arrangements, so the cost is certainly different. However, the supplier sometimes tells you a complex process to increase the price when quoting, while other simple processes will be used in actual production. Therefore, the purchaser's reading of drawings and knowledge of part processing determine your grasp of the cost, Therefore, the purchase of mechanical parts requires a comprehensive knowledge of machining.
Structural analysis method of Dalian castings
(1) In terms of design requirements, the parts in the machine can play the functions of support, accommodation, transmission, coordination, connection, installation and positioning, which is the basis for determining the main structure of the parts.
(2) From the aspect of process requirements, in order to make the blank manufacturing, processing, measurement, assembly and adjustment of parts smooth and convenient, the structures such as fillet, mold pulling slope and chamfer should be designed, which is the basis for determining the local structure of parts.
(3) From the perspective of practicality and aesthetics, it is not only required that the product can be used, but also required to be economical and beautiful. The structural shape should be considered from the perspective of aesthetics.
During centrifugal casting, the feeding conditions are improved due to the effect of centrifugal force, and the gas and non-metallic inclusions are also easy to be discharged from the liquid metal. Therefore, the structure of centrifugal casting is dense, and there are fewer defects such as shrinkage (shrinkage), porosity and inclusions; However, centrifugal casting also brings about casting defects such as hard material, internal and external sand and cloud spots.
The external chill is placed on the outer wall of the casting and placed in the molding sand. The chill is sprayed with paint. Generally, the chill can be separated from the casting during sand falling. Internal cooling iron is the part that needs to be cooled in the chill insert mold, so that the chill and the casting are fused into one. Internal cooling iron is mainly used in the production of heavy ferrous metal castings. The chilling effect of internal chill is much greater than that of external chill, so the dosage should be appropriate.
