1 Scope
This part specifies proof torque class, proof torque value and test method of wing nut applicable to national standard.
2 Proof Torque Class and Proof Torque Value
The proof torque class of wing nut is composed of a Roman numeral, which is only a code not expresses class difference. It's applicable to wing nut specified by national standard.
The proof torque of wing nut shall be in accordance with those specified in Table 1. Where test is conducted under normal temperature according to the method specified in Chapter 4, the thread of wing nut shall be free from thread-off or fracture and the wing part shall also be free from obvious deformation; after removing torque, nut shall be capable of being screwed out by hands or it shall be loosened by wrench but shall not exceed half thread. During test, if bolt is damaged, the test is invalid.
Foreword i
1 Scope
2 Proof Torque Class and Proof Torque Value
3 Test Methods
