A vermicular graphite cast iron scroll and its production process

Abstract

The invention discloses a vermicular graphite cast iron scroll plate and a production process thereof. The plate is prepared by casting vermicular graphite cast iron, a raw material for the plate comprises the following components of, by mass: 3.6%-4.0% of C, 1.6%-2.0% of Si, 0.4%-0.8% of Mn, 0%-0.25% of P, 0.01%-0.04% of S, 0.20-0.6% of Cu, 0.04-0.08% of Sn, 0.10%-0.3% of Cr and the balance Fe and accompanying impurities. According to the vermicular graphite cast iron scroll plate, in the raw material production process, 0.30%-0.40% of a modification treating agent is adopted to control the creep rate of the graphite form to be 20%-60%, the mechanical performance of the scroll plate is greatly improved, the tensile strength is larger than or equal to 450N / mm<2>, the yield strength is larger than or equal to 315N / mm<2>, the elongation rate is less than or equal to 3%, and the hardness range is HB200-HB250, and the durability life test is up to 2600 hours.

Description

technical field [0001] The invention relates to a vermicular graphite cast iron scroll and a production process thereof, belonging to the technical field of graphite cast iron. Background technique [0002] Common gray cast iron is used as the raw material for air conditioners in shopping malls and public transport, refrigeration for food preservation and refrigeration compressor core parts for cold chain transportation on the market. However, when the gray cast iron scroll disk used in the refrigeration system is applied to the heat pump scroll compressor under the high temperature difference condition, the problem of scroll fracture due to insufficient mechanical strength will occur under severe working conditions. , its mechanical strength cannot meet the needs of use. [0003] According to the morphology of graphite, gray cast iron can be divided into: ordinary gray cast iron, nodular cast iron, malleable cast iron and vermicular graphite cast iron. The graphite of ordi...

AI Technical Summary

Problems solved by technology

The working temperature of the refrigeration compressor is in the working range of -10°C to 60°C; the heat pump compressor is mainly used for heating and heating in winter in the north, and the working temperature is in the working range of -30°C to 90°C; the heat pump compressor The scroll disk, the core part, needs to withstand a working temperature difference as high as 120°C, but the scroll disk used for refrigeration compressors on the market can only withstand a working temperature difference of 70°C

As mentioned above, in the working environment with high temperature difference and harsh working conditions, the scroll made of ordinary gray cast iron may have the risk of fracture due to insufficient mechanical strength

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