JB/T 6054-2001 Process preparation principles for cold extrusion parts
Some standard content:
JB/T 6054--
2001
Previous
Preface
Revision of Process Preparation Principles. During the revision, editorial revisions were made to the original standard. This standard is a revision of JB/T6054---1992 "Cold Extrusion Parts", and the following contents were modified.
1. Note the formulas as formula (1) and formula (2), and explain that the calculation of the maximum deformation degree is determined by formula (1), and the calculation of the minimum deformation degree is determined by formula (2).
2． The meaning of the equivalent carbon content and the adjacent deformation degree of carbon steel materials in Table 1 can be obtained by the insertion method. From the date of implementation of this standard, it will also replace JB/T6054--1992. Appendix A of this standard is a reminder appendix.
This standard is proposed and managed by the National Forging Standardization Technical Committee. This standard was drafted by: Shanghai Jiao Tong University. The main drafters of this standard: Ying Yinghong, Zhao Zhen, Wu Gongming. This standard was first released in May 1992, and this is the first revision. 157
1 Scope
Mechanical Industry Standard of the People's Republic of China
Technological design principle for cold forging partJB/T6054-2001||tt ||Replaces JB/T6054--1992
This standard specifies the process preparation principles of cold extrusion parts, including process plan, deformation process, main process parameters, rough preparation and selection of required equipment.
This standard is applicable to ferrous metals and non-ferrous metals. 2 Referenced standards
The provisions contained in the following standards constitute provisions of this standard by being quoted in this standard. At the time of publication, the editions indicated were valid. All standards will be revised. All parties using this standard should explore the possibility of using the latest version of the following standards, GB/T8541-1997 Forging terminology
JB3/T6541-1993 Cold extrusion parts shape and structural elements 3 code
2α-
One positive extrusion die mouth angle, (°); reverse extrusion punch cone angle, (\
L. One cold extrusion part has bad hair Length, mm;
D——gross diameter of cold extruded parts,mtm;
P——cold extrusion extrusion force,MN;
force-cold extrusion unit Extrusion force, kN/mm2; D - outer diameter of cold extruded parts, mm;
d, - inner diameter of cold extruded parts, mm;
F, -- deformation of cold extruded parts Front cross-sectional area, mm2; F, - cross-sectional area after deformation of cold extrusion parts, mm; Ef section reduction rate, %;
[e]
R
allowed Deformation degree, %;
Extrusion ratio;
4 preparation principles
4.1 Cold extrusion deformation method
SrFo
F.||tt| |×100%
F
R
F
Cold extrusion deformation methods can basically be divided into forward extrusion, reverse extrusion, compound extrusion and upsetting extrusion Composite extrusion. For extruded parts, it can be one or a combination of 158
2001.10-01 Approved by China Machinery Industry Federation
4.2 Determination of cold extrusion process plan
IB/T 6054-200
4.2.1 The single deformation amount of cold extrusion parts should be within the allowable deformation degree [e] range 4.2.2. In addition to complying with the original test of Article 4.2.1, the reverse extrusion certificate must also meet the requirements of Articles 4.2 and 4.3 of JB/T65411993. 4.2.3 The roughness of the forward extrusion parts shall meet L,/D≤5, and 4.2.4 composite. The allowable deformation degree of extrusion is calculated based on one-way extrusion, and its value can appropriately exceed the allowable deformation degree of simple forward extrusion or simple reverse extrusion
4.2.5 When upsetting composite extrusion parts are formed in one step. , the rough deformation resistance should be greater than the extrusion deformation resistance. Cold extrusion parts with a length-to-diameter ratio of 1../D.2.5.
4.2.6 that exceeds the allowable deformation level of the thick part can pass. Add process steps to achieve it. 4.2.7 Cold extrusion parts with special performance requirements should be considered in the preparation of the T process. 4.2.8 The production of cold extrusion parts can also be combined with other processing methods. The process step block diagram is shown in Figure 1
e
Figure 1 Cold extrusion deformation 1-step block diagram
4.3 Cold extrusion deformation T sequence preparation principle
4.3.1 Cold The design of the extrusion deformation process mainly depends on the deformation resistance of the cold extrusion material and the economical mold design. 4.3.2 The design of the cold extrusion deformation process must consider the dimensional accuracy, shape complexity and surface quality of the cold extrusion parts. As much as possible, the intermediate softening and surface treatment steps can be omitted by adding deformation steps. 4.3.3 The cold extrusion deformation process must select reasonable rough softening treatment and surface lubrication treatment. 4.3.4 The cold extrusion deformation process must consider the design, manufacturing, life, cost and other factors of the cold extrusion die. 4.3.5 The cold extrusion deformation process is formulated to achieve production mechanization and automation as much as possible. 4.4 Main principles for determining cold extrusion process parameters 4.4.1 Determination of deformation degree
159
JB/T 6054—2001
The allowable deformation degree of various materials is shown in Table 1 . 4.4.1.1
Table 1 Allowable deformation degree of cold extrusion
Material
Pure aluminum
Material
Aluminum-magnesium alloy. Red copper oxygen-free copper
Duralumin, brass, magnesium
Carbon steel (carbon content 0.15%)
Carbon content or equivalent carbon content 0.2%
Carbon content Or equivalent carbon content 0.43%
martensitic stainless steel
austenitic stainless steel
note
forward extrusion
98
95
70
70
60
55
50
45
Equivalent carbon content is low alloy structure The alloying elements in steel are converted into (: content. The middle value of 2 carbon steel is calculated using the interpolation method
Tet.
degree extrusion
98
90 | | tt | | G | | tt | | t | | tt | =1, when the unit extrusion force reaches 2500N/mm*, the maximum allowable deformation degree can be calculated according to the rough annealing hardness HB according to formula (1), and the minimum allowable deformation degree can be calculated by formula (2), En250)mx = ( 55 ~ 60) → 3. 2 V160HB (%)Et250min =(55 -~ 60) -- 4.46 V160HB(%)
4.4.1.2 The optimal deformation degree of anti-extrusion et is in the range of 40%~60% Inside. 4.4.1.3 The degree of positive extrusion deformation should be reasonably selected according to the cross-sectional area of ??the extruded part. When the cross-sectional area is small, the value can be larger, and vice versa, the value should be smaller.
4.4.1.4 When cold extrusion is performed at one position, the deformation degree of each station should be distributed as evenly as possible. 4.4.1.5 When producing large quantities of cold extruded parts, the selected E value should be appropriately small. 4.4.2 Determination principle of deformation force
In practical applications, nomogram is usually used to determine the deformation force. The nomograms of the deformation forces of the three main extrusion methods of ferrous metals are shown in Figures 2, 3, and 4. See Appendix A for examples.
4.4.2.1 Calculation of the extrusion force of composite extrusion parts. Under the condition that one end is closed, the extrusion force can be calculated according to the maximum degree of deformation. 4.4.2.2 Deformation force of upsetting extrusion parts. According to the maximum cross-section Calculation. 4.5 Principles for preparation of cold extruded parts rough
4.5.1 Extruded parts rough can be made of plates, bars, and wires according to the shape of the cold extruded parts and technical and economic requirements. 4.5.2 Materials can be hot-rolled or cold-drawn. Blanking can be done by sawing, cutting, shearing and blue brittle punching. When hot-rolled materials are blanked by punching, deburring and shaping procedures should be added. 4.5.3 Bars are cut by shearing. Generally, the length-to-diameter ratio of the blanks is 1/D1.0. 4.5.4 The diameter of the hair is D. It should be 0.05~0.20mm smaller than the inner diameter of the shearing die. 4.5.5 The rough hair should be softened and lubricated. 4.6 Principles for selecting cold extrusion equipment
Cold extrusion equipment mainly includes mechanical presses, hydraulic presses and cold extrusion presses. Cold extrusion presses should be given priority when conditions permit. The selected cold extrusion equipment should meet the following requirements:
4.6.1. When using a mechanical press, the force-stroke curve and energy of the equipment should meet the requirements for the force-stroke curve and deformation work of cold extrusion parts.
160wwW.bzxz.Net
JB/T6054-2001
Extrusion equipment must have good rigidity and slider guide accuracy. 4.6.2
Extrusion equipment should have a pre-extrusion device
4.6.3
250
2000
1500
Qa|| tt||1000
500
The maximum unit squeeze is 2a=180, /D
2500
Note:
2000
1500| | tt | ||3
Ignore the influence of deformation speed
N/mm
(1=/\*.081
200
1500||tt ||500
9
system
maximum extrusion force P
20
R=F/F
4.5||tt ||30
0.2 0.4 0.5 0.6 0.65 0.7
0.75
100
5.5
20
③
0
(2)
20
15
MIN
ma
in
o
15
mm
@
0.8
=FD/F
Figure 2 Forward extrusion cold extrusion bottom force nomogram of solid steel parts 0.825|| tt||0.85
20
10
161
Note:
NW
③
JB/T 6054 --2001
200
44
Maximum single extrusion force P (when L/D.1)
300 2500 20001500-1000~500N/m16| |tt||14
12
10
8
20
60
50
4||tt ||230 years
20-
%
g
ar
flesh attack
The extruded hair should be softened before deformation Processing, ④
11
2.5
La
f
.-.
0 0.2\0.5'0.6||tt| |1.1
1.0
Fu
Cai
0.91
Chopsticks
0.8
0.7
2 The rough hair should be surface treated and lubricated before deformation. 3 The influence of deformation speed can be ignored,
35
160
1.40
4.5
120
100
60B
5.5
R=F/Fl
Punch diameter d, mm
70
65
60
55
50-
745
401
+35
+30||tt| |+25
20
15.
+10-
5
0.7 0.75
E(Fo-F>/F
1.2
o. 6h
P
0.4
E/Do
Figure 3 Cold extrusion of steel reverse extrusion parts Linuo mold diagram 162
N/mm
3000
2500
hour
1a
2000
1500| |tt||1000
②
6.5
?
500
0
mm
90||tt ||70
160
s
.40
30
20
10
heart||tt| |L
0.80.825
0.85
?
Return aspect ratio Lu/Da
?
2500||tt ||@
Note:
2000
.5
2.
0
0.80.
1000| |tt||1500
Maximum unit extrusion force P, N/mm2
Maximum extrusion force MN
Extrusion roughness should be softened before deformation
2. The damaged hair should be surface treated and lubricated before deformation. 3 The influence of deformation speed can be ignored,
JB/T 6054--2001
N/mm
2250
2000
-1750||tt ||1500
1250
1000
1750
mm2
1800
1600
1400
(2
0=
1.2
1.4
.61.82.0
R= Fa/F
②||tt| |2, 4.9, 6.0. 10. 0
2.4.3.0
d
@
n50 48 46 44 42 40 38 36 34 32 30 Fleece ring diameter D .
I piece outer diameter D
Steel hollow part forward extrusion cold extrusion force nomogram Figure 4
26
20
05
20
25
T
rate
48
$50
a
m|| tt | | 163 | | tt | | JB/T6054.2001 | No. 30 steel, bristle diameter D=35mm, outer diameter of extrusion part D,=25mm, bristle hardness is 140HB. bristle ring aspect ratio La/D2.0, die mouth angle 2α=120°, use Nomo Determine the positive extrusion cold extrusion force and unit extrusion force of the solid part, check Figure 2D, D =35mm, D, =25mm, intersection point a, press the arrow to the intersection point h with HB=l40 in ②, and go to center 1. ./1) 2.0 intersects with point c, goes to point d where it intersects 2α-120° in ④, and intersects point e with D,-35mm in @, its modular coordinate is the maximum extrusion force P=1.25MN, and its ordinate is The maximum unit extrusion force is 1220N/mm2. The material of A2 is No. 30 steel, the diameter of the hair is D45mm, the inner diameter of the extruded part is dl-35mm, the length-to-diameter ratio of the hair is 1/D.0.6, the hardness of the hair is 140HB, and the reverse extrusion force and unit extrusion force are determined using a nomogram. . Check Figure 3D,D. =45mmd=35mm, intersection point a.? Check the correction coefficient c0.97 of L/D-0.6 in 2, 140HB in 2 intersects at point b, ③ intersects with the correction coefficient 0.97 at point c, ① intersects with D. 45mm intersection point d, its ordinate is the maximum extrusion force P2.30MN, and the abscissa is the maximum unit extrusion force 1450N/mm. The material of A3 is No. 30 steel, and the rough diameter is D. =38mm, the outer diameter of the positive extrusion part Dl=30mm, the inner diameter of the positive extrusion part dl-25mm. The hardness of the hair is 140HB, and the aspect ratio of the hair is L. /D-2.0. The entrance angle of the die is 2α-90°. Use the nomogram to determine the extrusion force and unit extrusion force. Check Figure 4 (D, D=38mm, D=30mm, d=25mm, intersect a and b\, parallel to the oblique line and intersect the ordinate, point a intersects the abscissa point b, point b' points downward along the arrow and Point a intersects with point 0 to the right and extends oc to point l where it intersects with the abscissa in ②. Follow the arrow to intersect with HB=140 at point e, and intersect g with the line 1/D=2.0 in ③ to the left. Point h is parallel to the oblique line and intersects 2α-90°. Its abscissa k is the maximum unit extrusion force = 1.45kN/mm2. In ④, k is connected to the origin point ok, and point u intersects ok at point i. The abscissa is the maximum extrusion force P=0.93MN, then p=1. 45 kN/mm2, P-0. 93 MN.
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