Production method of high precision profile steel for fork

Abstract

The invention discloses a method for producing high-precision profile steel used in a fork lift truck. A cold drawing method is used for the production. The process steps are as follows: hot-rolled profile steel with the cross section tolerance of plus 1-2mm and the length of 2-8m is taken as a blank; a hard alloy is used for preparing a die head by slow feeding wire cutting method; the size of the cross section of the head of the profile steel blank with the axial length of 100-250mm is reduced so as to pass through the inner hole of the die head; the head of the profile steel blank axially passes through the inner hole of the die head which is fixed on a guide rail of a chain-wheel wire drawing machine, and the drawing head of the wire drawing machine clamps the profile steel blank which passes through the die head; a motor of the chain-wheel wire drawing machine is started, and drives the drawing head by a gear box, a chain wheel and a drag chain to move linearly along the guide rail, the profile steel blank with the tolerance of plus 1-2mm is drawn for a plurality of times into finished profile steel with the tolerance of plus or minus 0.2mm. The method can ensure the high precision of the profile steel, and greatly reduce the production cost.

Description

technical field [0001] The invention relates to a production method of section steel, in particular to a production (processing) method of high-precision section steel for forklifts. Background technique [0002] Forklift section steel, such as I-shaped, C-shaped or J-shaped section steel, has high requirements for its precision due to the objective requirements of forklift quality. The most basic requirement for the tolerance of each part of the cross-section is ±1mm, while the strict tolerance standard to ensure the quality of the forklift is ±0.2mm, and the best is ±0.1mm (that is, the high-precision steel). [0003] However, this objective requirement has become a technical problem that domestic and foreign forklift manufacturers have been puzzled over the years: [0004] At present, the section steel for forklifts at home and abroad is produced by hot extrusion, that is, hot extrusion process, and hot rolling, that is, hot rolling process. Its accuracy can fully meet ...

AI Technical Summary

Problems solved by technology

[0004] At present, the section steel for forklifts at home and abroad is produced by hot extrusion, that is, hot extrusion process, and hot rolling, that is, hot rolling process. Its accuracy can fully meet the requirements of the high-precision profile steel required to ensure the quality of forklifts, that is, the tolerance standard of each part of the profile steel cross-section is ±0.1, but due to hot extrusion, expensive large-scale equipment is required (investment of several hundred million yuan) Therefore, the price of its section steel is very expensive. For example, the current price of the Italian company is about 40,000 yuan per ton, which makes it difficult for forklift manufacturers to bear the burden;

[0005] If the hot rolling method is used to produce steel for forklifts such as a large-scale hot rolling company in Germany, the price of the steel produced by the hot rolling method is much lower than the price of the steel produced by the hot extrusion method, such as the current German company The price is about 18,000 yuan per ton, but due to the uneven radial pressure of the hot rolling method, the tolerance of each part of the cross-section of the section steel barely meets the basic requirement of forklift production, which is ±1mm, which is far from being guaranteed. For the quality of forklifts, the high precision of section steel, that is, the tolerance standard is ±0.2mm, not to mention the requirement of ±0.1mm

Images