Clean stainless steel precision castings by:
1. Dry test cleaning: Dry test cleaning includes friction cleaning and shot blasting, rust removal and shot blasting cleaning. The friction cleaning efficiency is low and the actual effect is not very good. Also known as dry shadow practice, it refers to shot blasting for rust removal and shot blasting. Shot blasting is to use compressed gas as a driving force to make the steel ball spray to the surface of the product workpiece at a faster speed to clean the dirt on the surface of the workpiece. Shot blasting is relatively flexible, and it is a more reliable shot blasting and derusting filling. The shot blasting machine is used to spray steel balls and clean the surface impurities of the workpiece.
2. Wet cleaning: Electro-hydraulic sand cleaning is to clean the shell under the action of the pressure of the electrical equipment. fluid power. In the whole process of precision casting, because the vibration frequencies of surface dirt and metal are different, the purpose of sand cleaning is achieved.
Cleaning methods and stress influencing factors of stainless steel castings
In the whole process of pouring, the stress caused by pouring is mainly thermal stress, change stress and mechanical hindering stress. This pressure value is greater than the strength of the metal at this temperature, and casting will cause cracks. During the whole casting process, the mechanical hindrance stress usually disappears after falling sand, which is a temporary stress. The stress is mostly thermal stress and change stress. The factors influencing the stress are as follows.
1. The problem of metal properties.
The larger the metal elastic mold, the greater its stress; for example, the stress of steel castings, white iron, and ductile iron is greater than that of gray cast iron, one of which is related to the elastic mold of the metal. The casting stress is positively correlated with the free-line expansion coefficient of the aluminum alloy. Under the condition that other standards remain unchanged, the stress of martensitic stainless steel is 50% larger than that of metallographic stainless steel, because the α value is large. The thermal conductivity of the aluminum alloy can affect the temperature difference between the thick and thin parts of the workpiece. In the same situation, the thermal conductivity of aluminum alloy is smaller than that of carbon steel, so when other standards are the same, alloy steel has a lot of stress.
2. The characteristics of the mold.
The greater the heat storage rate of the mold, the faster the cooling speed, the greater the temperature difference between the inside and the outside, and the greater the stress caused. When sand casting, metal molds are easier to cause greater stress than sand.
3. Casting standards.
Increasing the pouring temperature is equal to increasing the mold temperature, delaying the cooling speed, so that the temperature of each part of the workpiece tends to be the same, thereby reducing the stress.
4 Cast construction.
The greater the wall thickness difference, the greater the temperature difference between the thick and thick walls, and the greater the heat energy caused.
The cleaning methods and stress influencing factors of stainless steel castings are shared here first. There may be shortcomings. You can also ask me for feedback and improve together. Of course, you are also welcome to visit the factory for on-site guidance and progress together. The company mainly produces castings made of materials: Stainless steel, stainless iron, steel castings, alloy steel, special alloy steel, high-nickel alloy ductile iron, ductile iron, etc., with three production lines of silica sol process, composite process and water glass process, equipped with machining center and full CNC finishing equipment , The production of various finishing hardware.Fenghua Xinke Precision Casting Co., Ltd is a enterprise specializing in the manufacturing of Silica Sol Castings,Lost Wax Investment Castings,Coated Sand Castings and finished products in stainless steel,carbon steel and low alloy steel. Our company is a world class manufacturer and supplier of investment castings with silica sol or water glass process in China. We both have our own steel casting foundry and CNC machining factory,which enable us to supply both precision castings and finished products with an annual production capacity of over 20,000 tons. As OEM Agricultural Casting Manufacturers and Custom Construction Machinery Casting Factory, our products cover a wide range of industries including train & railway, automobile & truck, construction machinery, mining machinery, forklift, agricultural machinery, shipbuilding, petroleum machinery, construction, valve and pumps, electric machine ,hardware, power equipment and so on. We are capable to custom Forklift Casting according to customers’ drawings or samples.