Design For Hot Forging-1.docx

14

594

Chapter 14

596

Chapter 14

Chapter 14

598

FIG. 14.4 Steel forging for sample calculations.

For this part the flash parameters can be obtained from Eqs, 14.1 and 14.2.

602 TABLE 14.3

Chapter 14 Draft Allowances for Forgings

Materials Steels Aluminum alloys Titanium alloys Ni-based alloys

Hammer dies External Internal 5-7° 7-10°

Press dies External Internal 3-5° 5-7°

605

p/l.

(b)

FIG. 14.9 606

Typical blocker cross sections compared to the finish forging cross sections,

Chapter 14

FIG. 14.10 Forging sequence design for a connecting rod. (a) Mass distribution stages,

610

Chapter 14

626

Chapter 14

Forging Data: Forging Shape Complexity Factor, Fft Second Digit 0

1

<=1.5 1.0 2 1.05

0.9

2

1.25

0.75

1.3

0.7

3 1.0

2

1.05 3

>1.5and<=3.0

3

2 1.0

2

1.0

1.25

0.75

3

0.9

1.3 3

0.7

Chapter 14

628 Forging Data: Forging Shape Complexity Factor, Fjc

Second Digit

<=2.0 1.05

>2.0 and <= 5.0 0.9

1.15

0.85

0 4 1.25

5

0.65 1.35

1 4

5

0.6

Design for Hot Forging

635

Example: For the sample part the following data are available: Number of surface patches, Ns, is 7 and therefore Ms = 7/78.6 = 0.089. The average

640

Chapter 14

where Apb is the punch block area, given by I/plt W^ and Flck is a lock factor equal to 0.06 unless the die split line is cranked, in which case the factor is 0.065.

Design for Hot Forging

641

14.14.2 Billet Heating Costs The costs for heating the billet or bar end to the appropriate forging temperature can be estimated by determining the energy costs for heating. These can be

642

Chapter 14