Internal combustion engine supercharger box: jointly developed by GE company of the United States and CRRC, and undertaken by our company.
Material: special heat-resistant alloy cast iron, weight 360kg.
The product has strict performance requirements, and the casting body and cast attached test bar must meet the following requirements: tensile strength（ σ b) : 230-300mpa, hardness (HB): 190-220. The internal structure is complex, and the overall dimension is 700 * 700 * 400mm. It is mainly composed of high-temperature gas cavity, cooling water cavity and oil cavity. Each cavity has different shapes and is nested with each other. The wall thickness between the cavities is large and thin, which is very different from the overall dimension. In addition, the internal and external surfaces of the whole casting are not allowed to have any form of welding repair. The finished products need to conduct 0.6MPa air pressure test for each cavity respectively, and no leakage and bubbling are allowed. In addition, the machining geometric tolerance is only 0.009. At present, it meets the driving mileage of millions of kilometers without replacement. The annual supply volume is 500 sets.
Sand casting is a metal forming process. First, a three-dimensional sand mold is formed, and then the molten metal is poured into the cavity of the sand mold for solidification. After the metal parts are cooled and formed, remove the sand shell. Some sand castings need post processing after casting. Sand casting can produce all kinds of metal materials, including cast iron, special alloy steel and so on. Sand casting is an economical and highly efficient technology, which can flexibly adapt to the requirements of size and structural design. Sand castings usually need secondary processing to improve the accuracy of products.
QT500-7, HT250, RTQSi4Mo.
Marine diesel engine supercharger, train internal combustion engine supercharger, pumps, such as: GE, EMD, CRRC, Kesby, You Island, etc.