Efficient and high-quality inner hole machining method for ultra-large-cylinder-diameter cold drawn pipe

Abstract

The invention discloses an efficient and high-quality inner hole machining method for an ultra-large-cylinder-diameter cold drawn pipe, and belongs to the technical field of machining. The efficient and high-quality inner hole machining method for the ultra-large-cylinder-diameter cold drawn pipe comprises the steps that cold drawing is conducted, the allowance of an inner hole is 1.5-2 mm, and local jumping is smaller than or equal to 1.5 mm; straightening is conducted, and the overall-length curvature is smaller than or equal to 0.5 mm; rough turning is conducted, a 15-degree taper is adopted for a top disc of a machine tool workpiece, and the inner hole of the cold drawn pipe serves as the standard; boring is conducted; the workpiece rotates, a tool does not rotate, and the roundness of the inner hole of the cold drawn pipe is smaller than or equal to 0.2; annealing is conducted; the temperature of the cold drawn pipe is increased to 400 DEG C along with a furnace, and heat preservation is conducted for 2 hours; scraping and roll finishing are conducted; and the inner hole of the cold drawn pipe is machined at a time through a scraping and roll combined tool, and the scraping and roll combined tool comprises a semi-finish boring tool, a finish boring tool and a rolling tool. The efficient and high-quality inner hole machining method for the ultra-large-cylinder-diameter cold drawn pipe is suitable for machining the inner hole of the cold drawn pipe with the diameter being phi 300 mm, the machining procedures can be reduced, the production cost can be reduced, and the machining efficiency can be improved; and the quality of the machined inner hole is high, the straightness of the whole hole is smaller than or equal to 0.1, the roundness is smaller than or equal to 0.02, and it is guaranteed that the roughness is Ra0.2.

Description

technical field [0001] The invention relates to the technical field of mechanical processing, in particular to an efficient and high-quality inner hole processing method for a super-large bore cold-drawn pipe. Background technique [0002] At present, hydraulic cylinders with super large bores are used more and more in the manufacturing fields of construction machinery, aerospace machinery, petroleum machinery and mining machinery. Cold-drawn tubes for hydraulic cylinders play an increasingly important role in my country's hydraulic industry. The quality requirements are getting higher and higher, so the processing allowance of the cold-drawn tube has a great influence on the final utilization rate of the product, processing efficiency and production cost. [0003] In the existing technology, the machining process of the inner hole of the ultra-large-diameter cold-drawn tube is a two-step process of boring and honing. This process scheme has low efficiency. It takes more than...

AI Technical Summary

Problems solved by technology

[0004] The boring and rolling technology cannot be used. The main bottleneck problem is that the roundness of the inner hole of the ultra-large-diameter cold-drawn tube after boring and rolling is greater than 0.2mm, and the roundness of the general inner hole after processing is required to be 0.02-0.03mm;

[0005] Secondly, the straightness is poor, generally the whole body is above 0.7mm, which is far beyond the design requirements and cannot be used;

[0006] Boring can remove the allowance and preliminarily shape the inner hole. Honing and rolling mainly carry out inner hole finishing to improve roughness and precision, but the processing efficiency is low and the processing cost is high;