Preparation method of titanium alloy seamless pipe

Abstract

The invention provides a preparation method of a titanium alloy seamless pipe. The preparation method comprises the following steps: step 1, smelting titanium sponge and intermediate alloy for multiple times to obtain a titanium alloy cast ingot; step 2, heating the titanium alloy cast ingot obtained by smelting, carrying out drawing forging, and carrying out multi-heating-number upsetting and drawing above the transformation temperature of the titanium alloy and below the transformation temperature of the titanium alloy in a staggered manner to obtain a titanium alloy bar blank; step 3, punching a through hole in a titanium alloy bar, and performing boring to obtain a titanium alloy hollow bar blank; step 4, coating the inner surface and the outer surface of the heated titanium alloy hollow rod blank with lubricating agent, and then extruding the titanium alloy hollow rod blank to obtain a titanium alloy extruded pipe blank; step 5, performing one-time forming precision forging on thetitanium alloy extruded pipe blank to obtain a precision forging finished pipe blank; and step 6, conducting straightening and machining after overall heat treatment to obtain the titanium alloy seamless pipe. The titanium alloy seamless pipe manufactured by the preparation method has the advantages of being adjustable in pipe outer diameter and shape, high in size precision, high in structural uniformity and the like.

Description

technical field [0001] The invention relates to the technical field of titanium alloy production, and in particular to a method for preparing a titanium alloy seamless pipe with high structural uniformity by means of extrusion combined with precision forging. Background technique [0002] With the application of titanium and titanium alloys, the demand for titanium and titanium alloy seamless pipes currently used in ships, marine engineering, and marine exploration instruments has increased. The titanium alloy seamless pipes are mainly used in their working conditions. Equipment or components in harsh environments, such as the shell of an oil field logging instrument that needs to be placed thousands of meters underwater, must withstand high pressure, and must also withstand seawater and marine biological corrosion; Shells of deep ocean exploration instruments, pipelines with high pressure and corrosive media, etc. [0003] In the prior art, the manufacture of titanium allo...

AI Technical Summary

Problems solved by technology

[0004] Cross rolling piercing + hot continuous rolling process can realize piercing and forming at one time, low cost, relatively small consumption of titanium metal and tools, but high deformation temperature, severe deformation, difficult to control surface quality and material structure properties; at the same time, thermal tension The use of mandrelless empty rolling for diameter reduction will cause the inner surface of the seamless pipe to be polygonal, the outer surface is damaged and the inner surface is not round, so that the hot-rolled seamless pipe needs a large amount of surface grinding before delivery to meet the use requirements and dimensional accuracy

The extrusion process is used to prepare seamless pipes. Due to the drilling of the round bar billet and the extrusion process, the consumption of metal and tools will increase, which will increase the production cost of titanium alloy seamless pipes. Due to the extrusion lubrication problem, the inside and outside of the pipe The surface is prone to uneven deformation such as scratches, bulging, and pits; at the same time, the deformation of the inner and outer diameters of the pipe is inconsistent, and there is a deviation in the grain size. The size is limited by the extrusion die, and the inner and outer diameters cannot be adjusted.