A method for size control of large thin-walled cylinder castings

Abstract

The casting technology for steel castings of the present invention particularly relates to a method for controlling the size of large thin-walled cylinder castings. The method includes the steps of: taking the centerline of the cylinder body of the large thin-walled cylinder castings as a reference line for parting; Preset shrinkage seams between the exhaust pipe of the profiled surface and the cylinder block; preset shrinkage seams on the left and right parted cylinders respectively; preset process corrections on the inner side of the pipe wall of the exhaust pipe; respectively on the left and right sides The preset process correction amount on the side wall of the gantry; 3D hollow sand cores are set in the sand molds of the exhaust pipes on the left and right sides respectively. The invention overcomes the problem of unqualified casting size caused by the traditional production process, and solves the problem of free shrinkage of the pipe wall by using the method of size shrinkage joints; the 3D hollow sand box is placed in the sand core, so as to improve the receding property of the sand core and ensure the smoothness of the pipe wall. Free shrinkage; effective casting solves the problem that the center of the tube wall becomes longer in the shrinking length direction; and solves the problem of the design sticking amount of the tube wall in the length direction.

Description

technical field [0001] The invention relates to a casting technology for steel castings, in particular to the control of the size of a large-scale thin-walled cylinder casting. Background technique [0002] The cylinder block is the outer cylinder part of the oil and gas, steam turbine and other industries. Its general structure is a uniform-wall cylinder block and a thin-walled tube wall structure. The cylinder block structure includes an exhaust pipe and a cylinder block, which has the characteristics of thin-walled and super-long structure. However, for large, ultra-long, thin-walled cylinder castings, the shrinkage of the castings is hindered by the sand core inside the exhaust pipe, resulting in a longer distance between the center of the pipe wall and the side length of the overall casting of the pipe wall than the theoretical size. [0003] In the production process of thin-walled and super-long cylinder castings, due to the large length and size of the tube wall core...

AI Technical Summary

Problems solved by technology

[0004] The invention overcomes the problem of unqualified casting size caused by the traditional production process, provides a method for controlling the size of large thin-walled cylinder castings, and uses the method of size shrinkage joints to solve the problem of free shrinkage of the pipe wall; at the same time, a 3D hollow sand box is designed Put it in the sand core to improve the concession of the sand core and ensure the free shrinkage of the pipe wall

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