Sand Casting Manufacturing Technic
Generally it choose sand casting for large diameter butterfly valves. Here introduce the sand casting manufacturing technical procedures:
1. Pattern production. The pattern shall be produced according to technical drawing, showing all dimesions. It can wooden pattern for one pc products; it can be metal pattern for large quantities products. It include pair parts for one pattern. The pattern is produced by carving machine, manufactuering period 1~2 weeks.
2. Sand Box production. Put pair of patterns to sand box, fill box with enough sand, press the sand in box to assure stability of sand . Get pair of patterns out of sand box. Gather pair of patterns. These procedures are important for casting manufacturing.
3. Prepare to melte alloy material , assure the chemical components meet requirement of standard, to get the qualified liquid metal ( for cheical component and temperature ). We use electric furnace for environment protecting purpose.
4. Fill sand box with liquid metal. Pay attention fill not too quickly , assure fill sand box compleltel, without any empity. It’s dangerous to fill the liquid metal, coution danger.
5. After liquid metal in sand box solidified, clear the sand on surface of metal.
Polish surface of metal by machine, shutblast the matel to make casting have a better apperance.
6. Inspect the casting. In case any defect, need to repair or re-manufacture . If the casting pass the inspection, we take them to do valve production.
Above is brief introduction for sand casting manufacturing. Actually for smaller diameter butterfly valve, instead of sand casting, we use investment casting for better quality and apperence .
Valve casting is important for valve quality . ZFV keep to use good quality casting to assure valve quality, to seek long term business relations with customers.
Zhejiang Zhengfeng Valve.