Stainless steel is a metal that has a lot of applications when it comes to manufacturing various parts for different types of machines and equipment. Stainless steel has strength, durability, wear resistance, and especially outstanding corrosion resistance in a wide range of environments. Stainless Steel is a large family of alloys that contain a variety of elements, primarily iron with chromium and nickel, but may also contain molybdenum, manganese, silicon, vanadium and numerous others. This variety of compositions allows customers to choose an alloy meeting the particular needs of their product.
Gamma Foundries can meet the most challenging and stringent requirements for customers casting needs. We have the required professional personnel and equipment to produce quality work and expertise.
Stainless steel production through sand casting has the following steps in its process:
- Preparation of the Mold: Initially the mold is made which is a structure that has a cavity inside which is the shape of the part to be made. This is usually made of sand held together with a chemical binder or a combination of sand, clay, and water-packed together… In addition, extra components known as cores may need to be produced to create openings and passages in the casting.
- Assembly: After the components are ready, they need to be assembled. The two halves of the mold are opened up, the sand surface may require a coating to provide the required finish. The next step is to carefully assemble the cores in the mold and secure them in position. The top half of the mold is then placed in position and the mold is ready to pour.
- Melting and Pouring: While the mold was being assembled the melting team was preparing the metal. The foundry lab prepares the “charge” which is the ingredients for the particular alloy required. The furnace operator then charge the furnace with this batch of material and melt this, raising the temperature to the ideal temperature for the alloy and part. Once at temperature, the furnace is emptied into a ladle and the pourers carefully fill the mold from the ladle.
- Cooling: Now the mold along with the material inside is left to cool down. Depending on the alloy and size of the casting this could be a couple of hours or a few days. Opening a mold too early can be detrimental to getting the properties required as cooling a casting too fast prevents the required grain structure from forming.
- Finishing: After the mold with the casting still inside has cooled sufficiently the mold is broken open and the casting is carefully removed. The sand from the mold is then processed through a reclaimer ready to be used for more molds. The casting at this point still has the gating system attached, this is the channels and extra material needed to fill the mold effectively. This excess metal cut off and sent back to the melting department. The casting is then shot blasted to clean off any remaining sand and remove any grinding marks.
- Inspection & Testing: Castings all receive a close visual inspection for possible defects. In addition, depending on the customer requirement, they may undergo pressure testing, liquid penetrant test, radiography or other tests. When the casting was being poured some of the metal was poured into a coupon for chemical analysis and a test bar mold to confirm that the foundry did achieve the required properties that were specified.
Sand casting companies and foundries have achieved greater heights in quality and precision with this methodology of giving intricate shapes to stainless steel.
