JB/T 6541-1993 Shape and Structural Elements of Cold Extruded Parts JB/T6541-1993 Standard download and decompression password: www.bzxz.net

Machinery Industry Standard of the People's Republic of China
Cold extrusion parts
Subject content and scope of application
Shape and structural elements
This standard specifies the conditions that cold extrusion parts should follow Shape and structural elements. This standard applies to ferrous and non-ferrous metal cold extruded parts. 2Code
··Inner surface fillet radius of cold extrusion parts.mm; r,r.
R, R:...--Outer surface fillet radius of cold extrusion parts, mim:2α —Forward extrusion die mouth angle, ()
β--Reverse extrusion punch cone angle, (\); S
wall thickness of extruded parts, mm; ||tt| |Flange thickness or bottom thickness of extruded parts, mm;
h extruded parts with skin thickness, mm,
t,
D,
extruded parts Inner diameter, mm:
Outer diameter of extruded parts, mm;
Du---hair diameter, mm;
L-hair length, mm
L The length of the extruded part of the forward extrusion part, the depth of the hole of the reverse extrusion cup part, mmt --- the depth of the cavity of the extrusion part, mm.
3 Classification of cold extruded parts
3.1 Classification of cold extruded parts by shape
Condensation symmetry;
a.
b. Simple axisymmetric and asymmetric shapes:
c. Profiles with grooves, teeth and other shapes. 3.2 Cold extrusion parts are classified by process
3.2.1 The forward extrusion process is mainly divided into forward extrusion of solid parts (see Figure 1) and forward extrusion of hollow parts (see Figure 2). An example of the shape of a forward extrusion solid part is shown in Figure 3, and an example of the shape of a forward extrusion hollow part is shown in Figure 4. 3.2.2 The reverse extrusion T process is mainly divided into cup-shaped part reverse extrusion (see Figure 5) and cup-rod reverse extrusion pressure (see Figure 6). See the picture for an example of the shape of the reverse extrusion part? .
The Ministry of Machinery Industry of the People's Republic of China approved JB/T 6541 .93 on 1993-07-01
Implemented on 1994-07-01
175
176||tt| |Nai die
Concave die
Figure 1 Positive extrusion of solid parts
.93
IB/T 6541 --
Mold||tt| |shop
Picture 2 Positive extrusion of hollow parts
China middle w medium
Picture 3 Example of positive extrusion shape of solid parts
Fig. 4 Positive extrusion shape of hollow parts Example
Punch
Work piece
Concave algae
Lower punch
Figure 5 Cup-shaped part reverse extrusion
Figure (cup - Rod back extrusion
Punch mold
.Parts
A moldwwW.bzxz.Net
Lower punch
JB/T 6541-93
中080M国
Figure 7 Example of reverse extrusion part shape
3.2.3 The composite extrusion process is mainly divided into cup-cup composite extrusion (see Figure 8), cup-rod composite extrusion (See Figure 9), cup-rod composite extrusion (see Figure 10), etc.
composite extrusion part shape examples are shown in Figure 11. Punch mold
workpiece
concave mold.
Lower punch
Picture 8 cup-cup composite extrusion
Mold
pieces
-concave die
Lower punch
Picture 9 Cup - Rod Composite Extrusion Bottom
Punch
Mold
Workpiece
Lower Punch
Picture 10 Rod- Composite extrusion of rods
Zhongyoushu
Shattered by
h
Figure 11 Example of composite extrusion shape
3.2.4 Upsetting process It consists of upsetting and extrusion composites (see Figure 12). An example of the shape of a sensitive extrusion part is shown in Figure 13
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4 Structural elements of cold extrusion parts
4.1 Determine the structural elements. - General principles
a.
h.
,
d.
e.
f.
JB/T 6541-93
Figure 12 Upsetting and extrusion composite forming
Punch die
Concave die
Workpiece
Lower punch
Push pin
Mother in center
Figure 13 Example of shape of extruded parts
The structure of cold extruded parts must use the deformation characteristics of cold extrusion.T process to achieve as little cutting as possible Add T.; The structure of cold extruded parts must consider the changes in physical and mechanical properties caused by the deformation characteristics of the cold extrusion process: the structure of cold extruded parts must ensure sufficient die life; the structure of cold extruded parts must ensure forming and die life. Under the conditions, the forming steps should be minimized; the structure of cold extruded parts should consider the factors affecting the material and its subsequent heat treatment process: asymmetrically shaped cold extruded parts can be merged into symmetrical shapes for extrusion. 4.2 Length-to-diameter ratio of the cup-shaped reverse extrusion part
The aspect ratio L/d1 of the inner hole of the cup-shaped reverse extrusion part is shown in Table 1. Table 1 Aspect ratio of the inner hole of cup-shaped reverse extrusion parts
Material
Material
Ioid.
Pure
Aluminum
4.3 The ratio h/S of the bottom thickness and wall thickness of cup-shaped reverse extrusion parts is shown in Table 2. Copper
Copper alloy
Table 2 Bottom thickness and wall thickness ratio of cup-shaped reverse extrusion parts
Material
h/s
Material||tt ||Pure
Aluminum
0.5
4.4 The forward extrusion die mouth angle is 2α, and the reverse extrusion is called the die cone angle β. Copper and its alloys
1.0|| tt||Steel
2.5
1. The design of 2
2α angle should consider the rationality of the structure and the extrusion force per unit area. Generally, the normal extrusion mold door angle 2 is 90°-120° reverse extrusion shop 178
JB/T 6541--93
The die cone angle β is 7°~~9°. In special cases, it can be a flat-bottomed punch, and its intersection The interface should have rounded corners. 4.5 The position and thickness of the skin of composite extrusion parts. Under normal circumstances, the skin position of cup-cup extrusion parts should be placed in the middle (see Figure 14a), and the skin position of flat extrusion parts should be located at the human end (see Figure 14a). Ketu 14b).
The skin thickness is greater than or equal to the wall thickness S.
Door
Figure 14 Composite extrusion parts with skin position
4.6 Inner corner radius and outer corner radius of cold extrusion parts External corner radius R and inner The fillet radius is generally the same as the fillet radius of the part. In special cases, it can be appropriately increased in order to facilitate the metal flow (see Figure 15). It should be noted that the distance between the two fillets cannot be less than the fillet radius R of the positive wall thickness extrusion part, which is generally 3~10mm, and R2 is 0.5~1.5mm, see Figure 16. R2 | tt||D
Figure 16 Positive extrusion fillet radius
The depth 1 of the cavity should be less than the diameter d. When there is a cavity, the location of the cavity should be set at the symmetrical center of the part (see Figure 17). Figure 17 Pocket depth and location
Additional notes:
This standard is proposed by the National Forging Standardization Technical Committee. This standard is under the jurisdiction of the Beijing Mechanical and Electrical Research Institute of the Ministry of Machinery Industry. This standard is drafted by Beijing Institute of Mechanical and Electrical Engineering, Tianjin University, and Shanghai Jiao Tong University. The drafters of this standard are Li Chuanjin, Wang Yaozu, and Wu Gongming. 180
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