Two Differences Of Titanium Tubes
High production efficiency, short production process of welded titanium pipe. The length of the pipe is not limited, and it is suitable for the production of thin-walled pipes with relatively single specifications, varieties and grades and large batches. In recent years, there have been more than 80 welded pipes that have been built and prepared by state-owned enterprises and private enterprises, and the proportion of welded titanium pipes in titanium pipes will gradually increase. Titanium plates and titanium alloy thin-wall welded pipes are difficult to manufacture and are high-end products. With the breakthrough of domestic titanium strip production technology, China has successfully mass-produced titanium welded pipes.
The production process of titanium welded pipe is: titanium strip coil-slitting forming-welding-shaping and sizing-heat treatment-straightening-eddy current, ultrasonic testing-air tightness testing-finished welded pipe. Roller type continuous molding machine has many molding methods. For titanium welded pipes, the W bending forming method has good forming quality and is more suitable. The edge bending method is suitable for the production of welded pipes with a diameter greater than 200mm. The welding method of pipe seam mainly includes high-frequency welding and argon arc welding. Argon gas protection is required during welding and when the weld seam after welding is above 450T.
One is extrusion type called seamless titanium tube; the other is welding type called welded titanium tube. Extruded titanium pipes include cold rolled pipes, spinning pipes, and stretched pipes. Most of the titanium extrusion products belong to cold-processed pipe blanks, but also include some hot-extruded pipes, special-shaped parts, profiles and composite materials used as finished products. The minimum size of the pipe is 2mmx0.5mm in diameter. The maximum length of the high-precision ultra-long pure titanium seamless pipe can reach 15m. There are two methods to prepare titanium tube blanks: one is the drilling/piercing extrusion process, which has large metal loss, but the wall of the tube blank The thickness is uniform; the other is the cross-rolling piercing process, which has low metal consumption, but the thickness tolerance of the tube blank is large.
The hot extrusion of titanium plates and titanium alloys is carried out using an extruder. Using glass lubrication extrusion, the extrusion is larger than comparable encapsulation extrusion, titanium alloy profile glass lubrication P phase zone extrusion, the maximum extrusion ratio can reach 150, generally at a medium speed (50~120mm/extrusion. Titanium extrusion The pressure ratio is generally less than 30. I generally divide the titanium tube into two types. TC4 titanium alloy uses an extrusion ratio. The main lubricants used are grease, glass lubricant and metal coating. Glass lubrication extrusion is currently in the world The most advanced lubrication technology, but China's titanium pipe glass lubrication extrusion: the pressure has not yet reached the level of industrial application, the titanium alloy profile glass lubrication extrusion has achieved a breakthrough.
The coating lubrication is the coating of copper, mild steel or other metals on the outside of the blank. The metal cladding extrusion process is complicated, the cost is high, and the environmental pollution during the pickling process is serious. The extrusion die is generally preheated to 300~400 degrees. Under normal circumstances, the service life of each BE extrusion die is about 20 times. For profile extrusion, in order to improve the dimensional accuracy of thin-walled profiles and the wear resistance of tools and molds, the mold must be coated with zirconium dioxide coating by plasma method. When the specification is single and the batch is large, the oblique rolling piercing method can be used to produce tube blanks to obtain better technical and economic effects. There are two types of cross-rolling piercing methods: two-roll piercing and three-roll piercing.
