JB/T 5109-2001 in English

1 Scope

This standard specifies technological parameters and specification for technological design of bending for sheet metal.

This standard is applicable to cold bending forming of sheet metal on the press machine.

2 Normative References

The following standards contain provisions which, through reference in this standard, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below.

GB/T 4863-1985 General Terminology of Machine-Building Technology
GB/T 13914-1992 Tolerance of Dimensions for Stampings
GB/T 13915-1992 Tolerance of Angles for Stampings
GB/T 13916-1992 Unnoted Tolerance of Shape and Position for Stampings
GB/T 15055-1994 Permissible Stamping Variations in Dimensions without Tolerance Indication

3 Structure Technology of Bending Parts

3.1 Bending radius

3.1.1 Marking of bending radius

In dimensioning of bending parts, fillet radius shall be indicated.

3.1.2 Minimum bending radius

The minimum bending radius is the fillet radius of bending parts when the outer fiber of workblank produces no crack.

The minimum bending radius is only applied when necessary, and the bending radius shall be appropriately increased in all other cases.

Foreword i
1 Scope
2 Normative References
3 Structure Technology of Bending Parts
4 Precision of Bending Parts
5 Calculation of Bending Force
6 Calculation of Developed Length for Bending Parts
Annex A (Normative) Calculation Formulae for Developed Length of Bending Parts
Annex B (Normative) Simplified Calculation Sheet of Bending at 90°