When producing racks by cold rotary forging, the top punch and the rack teeth definitely intervene and thus the top punch has to be amended, which makes the technical designing processes difficult and complex (Han et al., 2016, “Cold Orbital Forging of Gear Rack,” Int. J. Mech. Sci., 117(10), pp. 227–242). In this study, a novel cold rotary forging method of producing racks is put forward to avoid the interventions between the top punch and the racks. Thus, the top punch need not be amended and the technical designing processes correspondingly become simple. In light of this presented method, a novel idea for cold rotary forging of producing multiple racks using one set of punch is motivated. The concrete researches are as follows: First, the mathematical models are developed and three kinds of key forging conditions in cold rotary forging of racks are calculated to avoid the interventions between the top punch and the racks. The first one is the condition that the top punch and the rack teeth do not intervene. The second one is the condition that the top punch and cylindrical surfaces of racks do not intervene. The third one is the condition that the top punch can be successfully constructed. On the basis of these three kinds of key forging conditions, the workpiece is optimized and the cold rotary forging processes of racks with constant and variable transmission ratio are examined using finite element (FE) simulations. The experimental researches are also conducted. The results show that for both racks with constant and variable transmission ratio, the obtained key forging conditions are effective and the presented cold rotary forging principles of producing multiple racks using one set of punch are feasible.

References

References
1.
Marciniak
,
Z.
,
1970
, “
A Rocking-Die Technique for Cold-Forming Operations
,”
Mech. Prod. Eng.
,
117
(11), pp.
792
797
.
2.
Zhang
,
M.
,
1984
, “
Calculating Force and Energy During Rotating Forging
,”
Third International Conference on Rotary Metalworking Processes
, Kyoto, Japan, Sept. 8–10, pp.
115
124
.
3.
Oudin
,
J.
,
Ravalard
,
Y.
,
Verwaerde
,
G.
, and
Gelin
,
J. C.
,
1985
, “
Force, Torque and Plastic Flow Analysis in Rotary Upsetting of Ring Shaped Billets
,”
Int. J. Mech. Sci.
,
27
(
11–12
), pp.
761
780
.
4.
Hawkyard
,
J. B.
, and
Smith
,
C. P.
,
1988
, “
The Influence of Elastic Die Distortion on Forming Force in Rotary Forging
,”
Int. J. Mech. Sci.
,
30
(
8
), pp.
533
542
.
5.
Pshenishnyuk
,
A. S.
, and
Hawkyard
,
J. B.
,
1989
, “
Critical Forming Force in Rotary Forging and the Application of Tungsten Carbide Dies
,”
Int. J. Mech. Sci.
,
31
(
6
), pp.
471
476
.
6.
Hawkyard
,
J. B.
,
Gurnani
,
C. K. S.
, and
Johnson
,
W.
,
1977
, “
Pressure-Distribution Measurements in Rotary Forging
,”
J. Mech. Eng. Sci.
,
19
(
4
), pp.
135
142
.
7.
Pei
,
X. H.
,
Zhou
,
D. C.
, and
Wang
,
Z. R.
,
1982
, “
Some Basic Problems of the Rotary Forging and Its Application
,”
Second International Conference on Rotary Metalworking Processes
(ROMP), Stratford-Upon-Avon, UK, Oct. 6–8, pp.
81
90
.
8.
Han
,
X. H.
, and
Hua
,
L.
,
2013
, “
3D FE Modelling of Contact Pressure Response in Cold Rotary Forging
,”
Tribol. Int.
,
57
, pp.
115
123
.
9.
Oh
,
H. K.
, and
Choi
,
S.
,
1997
, “
A Study on Center Thinning in the Rotary Forging of a Circular Plate
,”
J. Mater. Process. Technol.
,
66
(
1–3
), pp.
101
106
.
10.
Liu
,
G.
,
Yuan
,
S. J.
,
Wang
,
Z. R.
, and
Zhou
,
D. C.
,
2004
, “
Explanation of the Mushroom Effect in the Rotary Forging of a Cylinder
,”
J. Mater. Process. Technol.
,
151
(
1–3
), pp.
178
182
.
11.
Appleton
,
E.
, and
Slater
,
R. A. C.
,
1973
, “
Effects of Upper Platen Configuration in the Rotary Forging Process and Rotary Forging Into a Contoured Lower Platen
,”
Int. J. Mach. Tool Des. Res.
,
13
(
1
), pp.
43
62
.
12.
Standring
,
P. M.
,
Moon
,
J. R.
, and
Appleton
,
E.
,
1980
, “
Plastic Deformation Produced During Indentation Phase of Rotary Forging
,”
Met. Technol.
,
7
(
1
), pp.
159
166
.
13.
Nakane
,
T.
,
Kobayashi
,
M.
, and
Nakamura
,
K.
,
1982
, “
Deformation Behaviour in Simultaneous Backward Extrusion-Upsetting by Rotary Forging
,”
Second International Conference on Rotary Metalworking Processes
, Stratford-Upon-Avon, UK, Oct. 6–8, pp.
59
71
.
14.
Wang
,
G. C.
,
Zhao
,
G. Q.
,
Jia
,
Y. X.
, and
Yang
,
Y.
,
2000
, “
Densification Laws and Properties of Sintered Powder Compacts in Rotary Forging Process
,”
Trans. Nonferrous Met. Soc. China
,
10
(1), pp.
84
87
.http://www.ysxbcn.com/paper/paper_14562.html
15.
Wang
,
G. C.
, and
Zhao
,
G. Q.
,
2002
, “
Simulation and Analysis of Rotary Forging a Ring Workpiece Using Finite Element Method
,”
Finite Elem. Anal. Des.
,
38
(
12
), pp.
1151
1164
.
16.
Nowak
,
J.
,
Madej
,
L.
,
Ziolkiewicz
,
S.
,
Plewinski
,
A.
,
Grosman
,
F.
, and
Pietrzyk
,
M.
,
2008
, “
Recent Development in Orbital Forging Technology
,”
Int. J. Mater. Form
,
1
(
Suppl. 1
), pp.
387
390
.
17.
Han
,
X. H.
, and
Hua
,
L.
,
2009
, “
Plastic Deformation Behaviors of Cold Rotary Forging Under Different Contact Patterns by 3D Elastic-Plastic FE Method
,”
Mater. Trans.
,
50
(
8
), pp.
1949
1958
.
18.
Liu
,
G.
,
Yuan
,
S. J.
, and
Zhang
,
M. X.
,
2001
, “
Numerical Analysis on Rotary Forging Mechanism of a Flange
,”
J. Mater. Sci. Technol.
,
17
(1), pp.
129
130
.
19.
Yuan
,
S. J.
,
Wang
,
X. H.
,
Liu
,
G.
, and
Zhou
,
D. C.
,
1998
, “
The Precision Forming of Pin Parts by Cold-Drawing and Rotary-Forging
,”
J. Mater. Process. Technol.
,
86
(1–3), pp.
252
256
.
20.
Sheu
,
J. J.
, and
Yu
,
C. H.
,
2007
, “
The Cold Orbital Forging Die and Process Design of a Hollow-Ring Gear Part
,”
35th International MATADOR Conference
, Taipei, Taiwan, July, pp.
111
114
.
21.
Deng
,
X. B.
,
Hua
,
L.
,
Han
,
X. H.
, and
Song
,
Y. L.
,
2011
, “
Numerical and Experimental Investigation of Cold Rotary Forging of a 20CrMnTi Alloy Spur Bevel Gear
,”
Mater. Des.
,
32
(
3
), pp.
1376
1389
.
22.
Samołyk
,
G.
,
2014
, “
Numerical Investigation of Producing a Ti6Al4V Alloy Jaw Coupling Sleeve-Disk by Orbital Forging
,”
Metalurgija
,
53
(4), pp.
497
500
.https://hrcak.srce.hr/122172
23.
Calmano
,
S.
,
Hesse
,
D.
,
Hoppe
,
F.
,
Traidl
,
P.
,
Sinz
,
J.
, and
Groche
,
P.
,
2015
, “
Orbital Forming of Flange Parts Under Uncertainty
,”
Appl. Mech. Mater.
,
807
, pp.
121
129
.
24.
Han
,
X. H.
,
Dong
,
L. Y.
,
Hua
,
L.
, and
Zhuang
,
W. H.
,
2016
, “
Microstructure and Texture Evolution in Cold Rotary Forging of Spur Bevel Gears of 20CrMnTi Alloy Steel
,”
J. Mater. Eng. Perform.
,
25
(
3
), pp.
1182
1190
.
25.
Munshi
,
M.
,
Shah
,
K.
,
Cho
,
H.
, and
Altan
,
T.
,
2005
, “
Finite Element Analysis of Orbital Forming Used in Spindle/Inner Ring Assembly
,” 11th International Conference on Technology of Plasticity (
ICTP
), Nagoya, Japan, Oct. 19–24.http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.654.6865&rep=rep1&type=pdf
26.
Nam
,
C. H.
,
Lee
,
M. C.
,
Eom
,
J. G.
,
Choi
,
M. H.
, and
Joun
,
M. S.
,
2014
, “
Finite Element Analysis Model of Rotary Forging for Assembling Wheel Hub Bearing Assembly
,”
Procedia Eng.
,
81
, pp.
2475
2480
.
27.
Qu
,
J.
, and
Zhang
,
G. J.
,
2016
, “
Determination of Motion Equation of Rivet Head During Shaft Riveting Assembly Process for Wheel Hub Bearing Units
,”
ASME J. Manuf. Sci. Eng.
,
138
(
4
), p.
041006
.
28.
Grosman
,
F.
,
Madej
,
Ł.
,
Ziółkiewicz
,
S.
, and
Nowak
,
J.
,
2012
, “
Experimental and Numerical Investigation on Development of New Incremental Forming Process
,”
J. Mater. Process. Technol.
,
212
(
11
), pp.
2200
2209
.
29.
Merklein
,
M.
,
Plettke
,
R.
, and
Opel
,
S.
,
2012
, “
Orbital Forming of Tailored Blanks From Sheet Metal
,”
CIRP Ann. Manuf. Technol.
,
61
(
1
), pp.
263
266
.
30.
Merklein
,
M.
,
Lechner
,
M.
,
Gröbel
,
D.
,
Löffler
,
M.
,
Schneider
,
T.
,
Schulte
,
R.
, and
Hildenbrand
,
P.
,
2016
, “
Innovative Approaches for Controlling the Material Flow in Sheet-Bulk Metal Forming Processes
,”
Manuf. Rev.
,
3
, p.
2
.
31.
Han
,
X. H.
,
Jin
,
Q.
, and
Hua
,
L.
,
2017
, “
Research on Cold Orbital Forming of Complex Sheet Metal of Aluminum Alloy
,”
ASME J. Manuf. Sci. Eng.
,
139
(
6
), p.
061013
.
32.
Han
,
X. H.
,
Hua
,
L.
,
Zhuang
,
W. H.
, and
Zhang
,
X. C.
,
2014
, “
Process Design and Control in Cold Rotary Forging of Non-Rotary Gear Parts
,”
J. Mater. Process. Technol.
,
214
(
11
), pp.
2402
2416
.
33.
Han
,
X. H.
,
Zhang
,
X. C.
, and
Hua
,
L.
,
2016
, “
Calculation Method for Rocking Die Motion Track in Cold Orbital Forging
,”
ASME J. Manuf. Sci. Eng.
,
138
(
1
), p.
014501
.
34.
Han
,
X. H.
,
Hu
,
Y. X.
, and
Hua
,
L.
,
2016
, “
Cold Orbital Forging of Gear Rack
,”
Int. J. Mech. Sci.
,
117
, pp.
227
242
.
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