PURPOSE: To obtain the smooth flowing of fluid, to increase the resistance to the inner pressure and to easily and surely realize a method capable of integrally forming a throttle joint pipe with compression by using the joint pipe integrally compressive-forming a pipe wall having thick thickness being a metallic material.

CONSTITUTION: The seamless throttle joint pipe 1 integrally compressive-forming a throttle opening pipe part 2 and a enlarged opening pipe part 3 having the thick thickness with a metallic material is constituted. Further, the metal plate having the thick thickness is made to be a vessel-like base body and successively, the center of the bottom part in the base body is once pressed inward to make a projecting part and the projecting part is drawn outward and compressive-formed to a bulging part, and the tip part of the projecting part is cut and the whole base body is compressive-formed.