Patent ID: 11958454
Assignee: SANOH INDUSTRIAL CO., LTD.
Field: Mechanical elements (Mechanical engineering)
Classification: CPC B  F | IPC B  F

Claim 1:
2. The tube fitting of claim 1, wherein when, in a case in which a testing member corresponding to the mating member and a testing tube with a same outer diameter as the tube and having a testing ringlike portion corresponding to the ring-shaped portion are prepared and a fastening test including a fastening operation for fastening the tube fitting to the testing member with a predetermined tightening torque in a state in which the tube fitting is in contact with the testing ringlike portion and a disconnect operation for loosening the tube fitting after the fastening operation to disconnect the testing tube is repeated n times (where 1<n<6), a maximum axial force occurring in a first fastening test is defined as an initial axial force F1 in kN, a maximum axial force occurring in an n-th fastening test is defined as an n-th axial force Fn in kN, and a value obtained by −(Fn−F1)/(n−1) is defined as an axial force decrease rate α [kN/test round], 0<α<1.75 is true.