Short-flow high-efficiency production method for white brass alloy pipes

Abstract

The invention relates to a short-flow high-efficiency production method for white brass alloy pipes, belonging to the field of metal materials. In the method, a white brass pipe produced by virtue of a hot-cold-combined casting-mould horizontal continuous casting process is used as a blank; in a straight white brass pipe production process, the pipe blank is directly subjected to cold rolling with the total deformation amount of 50-90% and the single-pass deformation amount of not more than 20-25%; in a white brass coiled pipe production process, the pipe blank is subjected to the cold rolling deformation with the total deformation amount of not more than 50-70% and the single-pass deformation amount of not more than 20-25%, low-temperature recovery annealing is carried out at the temperature of 300-550 DEG C for 1-2 hours after the rolling is completed, an annealing protection atmosphere is formed by 2% of H2 and the balance of N2, and the annealed coiled pipe is bound to be subjected to once finishing in a serial continuous drawing way or triple continuous drawing before coil drawing; and in a subsequent coil drawing process, an average pass lengthening coefficient is 1.2-1.5, and the coil drawing speed is 1-1,000m/min. Compared with the traditional casting and rolling drawing method for producing the white brass pipes, the method provided by the invention has the advantages of short process flow, obviously decreased annealing frequency and low annealing temperature, and is beneficial to energy conservation and production efficiency improvement.

Description

technical field [0001] The invention belongs to the field of metal materials, and relates to a short-process and high-efficiency preparation method for white copper pipes, in particular to a short-process preparation method for thin-walled white copper straight pipes and coil pipes. Background technique [0002] The production of white copper alloy pipes at home and abroad mainly adopts the pipe-making process of "semi-continuous casting solid ingot-hot extruded tube billet-cold rolling-drawing" (referred to as extrusion-rolling method). , plus peeling, pickling, intermediate annealing and other processes, the total processing procedure is as many as more than 20 passes [see: Guo Li, Li Yaoqun, Condenser Tube Production Technology, P.30-32, Metallurgical Industry Press, 2007 ], leading to a series of problems such as long process flow, high energy consumption, low yield and high cost. [0003] The use of advanced short-flow process to produce cupronickel alloy pipes has bec...

AI Technical Summary

Problems solved by technology

Since the inner and outer surfaces of the continuous casting billet are prone to defects such as orange peel, segregation, microcracks, and wrinkles, the inner and outer surfaces must be milled before the subsequent processing of the billet. On the one hand, it increases the process and reduces the yield. On the other hand, defects on the inner surface of the tube blank (such as inner surface wrinkles) can only be brushed and milled (polished) with a wire brush, which is difficult to effectively eliminate and is brought into subsequent processing procedures, which seriously affects the quality of the product

In addition, the ordinary horizontal continuous casting billet is a well-developed radial columnar grain structure with low density, which is not conducive to the axial extension deformation of subsequent cold working (rolling, drawing)

[0005] Adopt the production method of "preparation of small-diameter thin-walled tube billet by continuous directional solidification - straight drawing or coil drawing" [see: Xie Jianxin et al., Short-process preparation process of copper and copper alloy precision pipes, Chinese invention patent, ZL200710065281.9, 2009- 06-10], high-quality pipes with continuous columnar crystal structure can be prepared, but the diameter and wall thickness of the prepared pipes are small, and the continuous casting speed is slow, which is only suitable for small batch production of high-quality white copper pipes, and it is difficult to meet large Large-scale industrial production needs