Co-operating organizations
Foreword
Scope
Section one: Dimensional tolerances for steel drop and
               press forgings
1 General remarks - drop and press forgings
1.1 Scope of Section one
1.2 Tolerance grades
1.3 Special tolerances
2 Information required in determining tolerances
         - drop and press forgings
3 Categories of tolerances - drop and press
         forgings
3.1 Scope of categories
3.2 Definition of categories
3.2.1 First group of tolerances
3.2 1.1 Length, width and height tolerances
3.2.1.2 Mismatch tolerances
3.2.1.3 Residual flash (and trimmed flat) tolerances
3.2.1.4 Pierced hole tolerances
3.2.2 Second group of tolerances
3.2.2.1 Thickness tolerances
3.2.2.2 Ejector mark tolerances
3.2.3 Third group of tolerances
3.2.3.1 Straightness and flatness tolerances
3.2.3.2 Tolerances for centre-to-centre dimensions
3.2.4 Other categories of tolerances
3.2.4.1 Fillet and edge radii tolerances
3.2.4.2 Burr tolerances
3.2.4.3 Surface tolerances
3.2.4.4 Tolerances on draft angle surfaces
3.2.4.5 Eccentricity tolerances for deep holes
3.2.4.6 Tolerances for unforged stock
3.2.4.7 Tolerances for deformation of sheared ends
4 Use of tables
4.1 Tables 1 and 2 or 7 and 8. Tolerances for
         length, width and height, residual flash (and
         trimmed flat), and mismatch
4.2 Tables 3 and 4 or 9 and 10. Tolerances for
         thickness and ejector marks
4.3 Tables 5 and 11. Tolerances for straightness
         and flatness; tolerances for centre-to-centre
         dimensions
4.4 Tables 6 and 12. Tolerances for fillet and edge
         radii; tolerances for burrs
5 Design procedure - drop and press forgings
5.1 Information required by the forger
5.2 Preparation of forging drawings
5.3 Indication of dimensions on forging drawings
5.4 Indication of tolerances on forging drawings
5.5 Importance of forging drawing
Appendix
A Deviations of form - drop and press forgings
Section two: Dimensional tolerances for steel upset
               forgings made on horizotal forging
               machines
6 General remarks - upset forgings
6.1 Scope of Section two
6.2 Special tolerances
7 Definitions and principles of application -
         upset forgings
7.1 Definition of an upset portion of a forging
7.2 Application of tolerances to double-ended upset
         forgings
7.3 Definition of unforged stock
8 Information required in determining tolerances
         - upset forgings
9 Categories of tolerances - upset forgings
9.1 Scope of categories
9.2 Definition of categories
9.2.1 First group of tolerances
9.2.1.1 Diameter tolerances
9.2.1.2 Tolerances on step dimensions
9.2.1.3 Length tolerances
9.2.1.4 Tolerances for mismatch and eccentricity
9.2.1.5 Tolerances for local deviations from original
         bar stock diameter
9.2.1.6 Residual flash and trimmed flat tolerances
9.2.1.7 Tolerances on internal dimensions including
         diameters of holes
9.2.2 Second group of tolerances
9.2.2.1 Thickness tolerances
9.2.3 Third group of tolerances
9.2.3.1 Straightness and flatness tolerances
9.2.3.2 Tolerances for centre-to-centre dimensions
9.2.4 Other categories of tolerances
9.2.4.1 Fillet and edge radii tolerances
9.2.4.2 Tolerances for parting line fins and trimming
         burrs
9.2.4.3 Eccentricity tolerances for deep holes
9.2.4.4 Tolerances for deformation of sheared ends
9.2.4.5 Surface tolerances
9.2.4.6 Tolerances on draft angle surfaces
10 Use of tables - upset forgings
10.1 Tables 1 and 7. Tolerances for diameter,
         length, residual flash (and trimmed flat),
         mismatch and eccentricity
10.2 Tables 3 and 9. Tolerances for thickness
10.3 Tables 5 and 11. Tolerances for straightness
         and flatness; tolerances for centre-to-centre
         dimensions
10.4 Tables 6 and 12. Tolerances for fillet and edge
         radii; tolerances for parting line fins and
         trimming burrs
11 Design procedure - upset forgings
11.1 General
11.2 Indication of tolerances on drawings for upset
         forgings
Appendix
B Deviations of form - upset forgings
Section three: Tables of tolerances for use when
               specifying in metric units
1 Length, width, height, mismatch, residual flash
         and trimmed flat of drop, press and upset
         forgings (normal tolerances)
2 Length, width and height of drop and press
         forgings (normal tolerances)
3 Thickness for drop, press and upset forgings
         and ejector marks for drop and press forgings
         (normal tolerances)
4 Thickness and ejector marks for drop and press
         forgings (close tolerances)
5 Straightness, flatness and centre-to-centre
         dimensions for drop, press and upset forgings
6 Fillet, edge radii and burrs for drop, press
         and upset forgings
Section four: Tables of tolerances for use when
               specifying in inch units
7 Length, width, height, mismatch, residual flash
         and trimmed flat of drop, press and upset
         forgings (normal tolerances)
8 Length, width and height of drop and press
         forgings (normal tolerances)
9 Thickness for drop, press and upset forgings
         and ejector marks for drop and press forgings
         (normal tolerances)
10 Thickness and ejector marks for drop and press
         forgings (close tolerances)
11 Straightness, flatness and centre-to-centre
         dimensions for drop, press and upset forgings
12 Fillet, edge radii and burrs for drop, press
         and upset forgings
Section five: Quantity tolerances for steel drop and
               press forgings and for upset forgings
               made on horizontal forging machines
12 Quantity tolerances