Method for improving quality of inner surface of titanium alloy seamless steel tube

Abstract

The invention provides a method for improving the quality of the inner surface of a titanium alloy seamless steel tube. The method comprises the following steps that a glass powder lubricating agent is prepared and wrapped into a cylinder with the height being 70 mm and the bottom area diameter being 50 mm through aluminum foil paper, and the outer surface of the cylinder is wrapped with asbestos cloth; a centering hole is punched; piercing is conducted; the glass powder lubricating agent prepared in the first step is injected into the centering hole of a titanium alloy seamless steel tube blank after the blank is discharged out of a circular furnace, and a cross-rolling piercing unit is started for piercing rolling of the titanium alloy seamless steel tube; and after piercing is completed, the high-temperature titanium alloy tube is subjected to continuous rolling, sizing and straightening, and the final finished titanium alloy seamless steel tube is formed. The method for improving the quality of the inner surface of the titanium alloy seamless steel tube has the beneficial effects that the problem that the top of a cross-rolling piercer for hot-rolling piercing of the titanium alloy seamless steel tube is prone to adhesion and caking, and consequentially defects on the inner surfaces of the oil tube are increased is solved, the warping rate of the inner surface of the finished oil tube is decreased to 10%, the inward folding defect rate is decreased by 50%, the production cost is reduced, and the delivery time of finished products is shortened by one time.

Description

technical field [0001] The invention relates to the thermal processing technology of titanium alloy pipes, and in particular provides a method for improving the inner surface quality of titanium alloy seamless pipes when producing titanium alloy seamless pipes. Background technique [0002] Titanium alloy has the characteristics of lower thermal conductivity than ordinary carbon steel, slow heat dissipation, difficult metal processing at high temperature, and narrow temperature range during hot processing. Traditionally, cold extrusion molding is used, but the cost is high and the yield is low. In order to reduce production costs, titanium alloy seamless pipes can adopt hot perforation + continuous rolling + sizing rolling process, but due to their poor high temperature plasticity, they are easy to be stuck by perforated plugs, resulting in excessive loss of production tools, and sticking titanium Alloy plugs can easily scratch the inner surface of the steel pipe. According...

AI Technical Summary

Problems solved by technology

[0002] Titanium alloy has the characteristics of lower thermal conductivity than ordinary carbon steel, slow heat dissipation, difficulty in metal processing at high temperature, and narrow temperature range during hot processing. Traditionally, cold extrusion molding is used, but the cost is high and the yield is low.

In order to reduce production costs, titanium alloy seamless pipes can adopt hot perforation + continuous rolling + sizing rolling process, but due to their poor high temperature plasticity, they are easy to be stuck by perforated plugs, resulting in excessive loss of production tools, and sticking titanium The alloy head is very easy to scratch the inner surface of the steel pipe

According to on-site statistics, when rolling titanium alloy oil pipes, without any lubrication measures, the scarring of the plug will lead to different degrees of defects such as folding, warping, cracks and other defects on the inner surface of the produced oil pipes, which greatly increases Subsequent modulus repairs are limited, and serious defects will make the entire oil pipe scrapped, increasing production costs and labor intensity