Forming process of titanium tee pipe fittings

For common titanium tee pipe fittings, because of its small diameter and thin wall, and require parts to withstand high pressure, casting method to manufacture not only casting difficult and its quality can not be guaranteed. If two straight pipes are welded, because the weld is the space intersecting line of two cylinders, the cutting and welding operation are difficult to grasp, and the part size is small, can only be welded from the outside, and the inner wall welding quality is not easy to maintain. Even if casting and welding can complete their shape manufacturing, because they inevitably have porosity slag inclusion in the process, this and process defects are not allowed to exist for medium and high pressure pipelines.

Technical personnel have thought of using die forging or radial extrusion process to make T solid bad material first, and then horizontal and vertical drilling methods, but the experimental results show that the quality of titanium tee pipe fittings is not easy to maintain, in addition, this process has many processing procedures, large equipment required, low utilization of metal materials shortcomings.

Finally, it is decided to use the straight tube extrusion forming, the blank filled with packing into the mold cavity, the upper and lower molds close the mold, and then use the same diameter and size of the pipe rod (2 pieces), from both sides of the same speed to push, the titanium tube in the mold cavity under the pressure of both ends must produce plastic deformation; Upsetting or extruding along the radial hole of the die.

Because the tube has been filled with incompressible filler, the upsetting deformation is impossible, so the straight tube is extruded from the radial hole opened on the mold with the filler under the action of pressure. In order to prevent the extruded radial pipe from bursting under the internal pressure of the packing, an ejector rod is installed in the radial hole of the mold, and sufficient compressive stress is applied to the extruded radial branch pipe.

When the extruded branch pipe reaches the size requirement, the required titanium tee pipe can be obtained by opening the die and removing the filler. Practice shows that the wall thickness of the extruded tee pipe is the same in three directions, the upsetting deformation is small, and the height of the extruded part is 2 ~ 3 times of the pipe diameter. In addition, because the filler and titanium tube move synchronously in the mold cavity, there is no mechanical scratch on the inner wall of the pipe fitting, and the size and quality meet the requirements of the drawing.