Three-roller planetary rolling method for rolling brass tube

Abstract

The invention discloses a three-roller planetary rolling method for rolling a brass tube. The method is characterized by comprising the following steps of: making the head of a tube blank into a conical surface; selecting a mandril, wherein a unilateral gap L between the mandril and the internal wall of the tube blank is not greater than 2.5mm; before rolling the tube blank by using a three-roller planetary rolling machine, preheating the tube blank to the temperature of between 100 and 500 DEG C first and then feeding the preheated tube blank into the three-roller planetary rolling machine for rolling; spraying emulsified liquid on rollers when rolling, wherein the spraying intensity of the emulsified liquid is of between 0.025 and 0.045MPa; purging by using a purging device arranged at the entrance of the three-roller planetary rolling machine to prevent the emulsified liquid from refluxing so as to prevent the tube blank from contacting the emulsified liquid before entering a rolling region; and processing a tubing rolled out from the exit of the three-roller planetary rolling machine into a finished product by drawing. The method has the advantages that: the brass tube is preheated when rolling, so that the rolling temperature of the brass tube exceeds a medium temperature brittle range of between 400 and 600 DEG C when the brass tube is rolled, namely good quality of a rolled tube body is achieved because of avoiding the medium temperature brittle range.

Description

technical field [0001] The invention relates to a three-roller planetary rolling method for rolling a brass tube. Background technique [0002] Adding aluminum to brass significantly reduces the α-phase region, and when the aluminum content is high, the γ-phase will appear, which improves the strength and hardness of the alloy, but greatly reduces the plasticity of the alloy; the brass contains 22% to 24% Zn, 1.0% to 3.0% Al HAl77-2 aluminum brass not only has good processing performance, casting performance and high mechanical properties, but also has good thermal processing performance. [0003] Compared with copper, HAl77-2 aluminum brass has extremely low plasticity at 400°C to 600°C, and its elongation at around 500°C is less than 10%, which means there is a medium temperature brittle zone. Therefore, with the increase of rolling temperature and the intensification of deformation, in the temperature range of 400 ° C to 600 ° C, the brass tube is easy to crack during th...

AI Technical Summary

Problems solved by technology

But so far, there is no technology that can control the temperature of the tube billet during the rolling process to solve the cracking of the brass tube rolling and realize the three-roller planetary rolling of the brass tube

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