A niobium tube forming process, belongs to the field of precious metal seamless steel tube processing and manufacturing, overcome the traditional process heating time is long, temperature control is not accurate, low yield defects. Including the following production steps: 1. 2. Play? 50 hole; 3. Finish the outer surface and end face of the car; 4. The inside and outside surfaces are coated with water glass; 5. Induction furnace heating; 6. Spray glass powder on inner and outer surfaces; 7. Hot expanding hole; 8. Induction furnace heating; 9. Spray glass powder on inner and outer surfaces; 10. Extrusion molding; 11. Straightening; 12. Surface sandblasting, flat head, size inspection, ultrasonic inspection after packaging. The method of glass powder protection in this process can greatly shorten the heating time from 6 to 10 hours to about 5 minutes, and can directly measure the temperature of the billet, so that the process control is easier, and the yield of finished material is increased from 60 to 75% to more than 80%.
Because of its small neutron capture cross section and high thermal conductivity and strength, niobium is used as nuclear fuel cladding material, nuclear fuel additive and heat exchanger structural material in atomic reactors. Nb in the traditional extrusion process, material in the material, hit 080~160 through hole, sealed by copper sheath, resistance furnace or annular furnace preheating, induction furnace heating, and then directly into the extruder extrusion molding. Heating time 6~10 hours, the yield of 60~75%.
If improved for the use of glass powder protection process, it can be W to shorten the heating time, from 6 to 10 hours to about 5 minutes, W can directly measure the temperature of the material, so that the process control is easier, the rate of finished material from 60 to 75% before W to 80%W.
Induction heating: primary induction furnace target temperature of 950~1100°C, secondary induction target temperature of 1050~1100°C. 2 hot reaming: the size of the reaming cone is 135mm. Vp68/2886 and EG6807S1I are used for lubrication of the outer surface of the smooth material. Yang 059] 3. 3, extrusion parameters: extrusion ratio is 7.2, after extrusion, the pipe length is 6m.
