Manufacturing method of super duplex stainless steel single-stage double-suction centrifugal pump case

Abstract

The invention discloses a manufacturing method of a super duplex stainless steel single-stage double-suction centrifugal pump case in the technical field of casting of fluid conveying equipment. The manufacturing method comprises the steps of box opening and riser gas cutting. During box opening, a box is opened after casting of a cast piece is finished and a riser is solidified, the time when thecast piece is solidified and the body temperature is larger than 1000 DEG C is determined through simulation software, the time is the box opening time, and the box opening time is smaller than 1h. During riser gas cutting, a pouring gate, the riser and molding sand are removed after box opening, the temperature is monitored at the same time, when the temperature is reduced to 700 DEG C, the castpiece must enter a furnace to be heated, it is ensured that the cast piece temperature is larger than 600 DEG C in the sand shakeout and riser gas cutting process, after the pouring gate, the riser and the molding sand are cleaned up, the cast piece is directly put into the furnace for heat treatment, and the heat treatment temperature is 1060 DEG C. Compared with a cast piece manufactured through an existing conventional casting process, the product is free of cracks, and the percent of pass of the product reaches 96%.

Description

technical field [0001] The invention belongs to the technical field of casting of fluid conveying equipment, and relates to a manufacturing method of a super duplex stainless steel single-stage double-suction centrifugal pump casing, in particular to a manufacturing method of a super duplex stainless steel single-stage double-suction centrifugal pump casing. Background technique [0002] Centrifugal pumps are equipment used to transport slurry containing solid particles, and can be widely used in electric power, metallurgy, coal, building materials and other industries, such as hydraulic ash removal in thermal power plants, slurry transportation in metallurgical beneficiation plants, coal slurry and heavy medium transportation in coal washing plants Wait. [0003] The basic structure of the centrifugal pump is composed of six parts: impeller, pump casing, pump shaft, bearing, sealing ring and stuffing box. The pump casing of the centrifugal pump is processed by casting, incl...

AI Technical Summary

Problems solved by technology

The existence of harmful phases leads to extremely brittle products, which are prone to brittle cracks and lead to scrapping of castings

The material is highly sensitive to temperature, and the precipitation of harmful phases is particularly concentrated in the two temperature ranges of 600-800°C and 400-500°C, especially after the first temperature range of 600-800°C, in the second temperature range The temperature range of 400-500°C is particularly dangerous, and the tendency of brittleness is large. Therefore, the qualified rate of cast iron-chromium-nickel-molybdenum corrosion-resistant duplex stainless steel single-stage double-suction centrifugal pump casing with the existing casting process is only 10%.

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