Forming Technology of Titanium Tee Fittings

For common titanium tee fittings, because of their small diameter and thin wall, the parts are required to withstand high pressure. It is not only difficult to manufacture by casting method, but also its quality cannot be guaranteed.

If two straight pipes are welded and formed, because the weld is a space intersecting line between two cylinders, it is difficult to control the blanking and welding operations. Moreover, the size of the parts is small and can only be welded from the outside, and the welding quality of the inner wall is difficult to maintain. 

Even if casting and welding can complete its shape manufacturing, because they inevitably have pores and slag inclusions in the process, this and process defects are not allowed to exist for medium and high pressure pipelines.

Technicians had envisaged using die forging or radial extrusion process to first make T-shaped solid bad material, and then drill horizontally and vertically respectively, but the experimental results show that the quality of titanium tee pipe fittings is not easy to maintain, in addition, This process has the disadvantages of many processing steps, large equipment required, and low utilization rate of metal materials.

After that, it is decided to use a straight tube and extrude it, put the straight tube blank filled with filler into the mold cavity, close the upper and lower molds tightly, and then use the same size as the pipe diameter. The side is pushed at the same speed, and the titanium tube in the die cavity must be plastically deformed under the pressure at both ends; upsetting or extrusion along the radial hole of the die.

Because the tube is filled with incompressible fillers, upsetting deformation is impossible. Therefore, the straight tube is extruded from the radial hole opened on the die together with the filler under pressure. In order to prevent the extruded radial tube Under the action of the internal pressure of the filler, it bursts, and a mandrel is installed in the radial hole of the die to apply sufficient compressive stress to the extruded radial branch pipe.

When the extruded branch pipe meets the size requirements, open the mold and take out the parts, clean out the filler, and then the required titanium three-way pipe fittings can be obtained. Practice shows that the extruded three-way pipe fittings have the same wall thickness in three directions, and the upsetting deformation is small. , the height of the extruded part is 2 to 3 times the diameter of the pipe; in addition, because the filler and the titanium pipe move synchronously in the mold cavity, the inner wall of the pipe fittings has no mechanical scratches, and the size and quality meet the requirements of the drawings.