JB/T 9177-1999 JB/T 9177-1999 Structural elements of steel die forgings JB/T9177-1999 Standard download decompression password: www.bzxz.net

JB/T 9177--1999
This standard is a revision of JB/Z295-87 "Technology and Structural Elements of Steel Die Forgings". Compared with JB/Z295-87, the main technical content of this standard has been changed as follows: 1) The name of the standard has been changed from "Technology and Structural Elements of Steel Die Forgings" to "Structural Elements of Steel Die Forgings". 2) The contents that are identical to G13/T12361--1990 "General Technical Conditions for Steel Die Forgings" and GB/T12362-1990 "Tolerances and Machining Allowances for Steel Die Forgings" have been deleted. 3) Add 4.1\Round corner radius of contraction section, multi-step section, gear spoke and crankshaft (DIN75231986 version) 4) The original 3.6 "minimum bottom thickness and rib width of different cross-sectional shapes" was changed to 4.2 "minimum bottom thickness" and 4.3 "minimum wall thickness, rib width and rib end fillet radius (DIN7523-1986 version).
5) The original 3.7.1. The minimum punching diameter of forgings was $25mm, which was changed to 3.4.1 and 20mm. This standard replaces JI3/Z295-87 from the date of implementation. This standard is proposed and managed by the National Forging Standardization Technical Committee. The responsible drafting unit of this standard: Shanghai Automobile Forging General Plant. The main drafters of this standard: Hu Jiuxi, Shu Xingchang 337
1 Scope
Mechanical Industry Standards of the People's Republic of China
Steel Die Forgings
Structural Elements
Structural main factors for steel die forgingsJB/T 9177 ---1999
Replaces JB/7.295-87
This standard specifies the design parameters and die forging dimension marking and measurement methods for "contracted section, multi-step section, gear spoke, and crankshaft groove fillet radius", "minimum bottom thickness", "minimum wall thickness, rib width and rib end fillet radius", "minimum punching diameter, blind hole and skin thickness" and "minimum web thickness" of steel hot die forgings. This standard is applicable to steel hot die forgings (hereinafter referred to as forgings) produced on die forging hammers, hot die forging presses, screw presses and flat forging machines. 2 Definitions
This standard adopts the following definitions.
2.1 Internal groove fillet
Points to the center of the forging. The radius of the inner fillet of the forging is called the inner groove fillet (rA in Figure 1). 2.2 External groove fillet
The radius of the inner fillet of the forging pointing to the flash is called the outer groove fillet (r in Figure 1). 2.3 Unrestricted web (open web)
The web in which the metal can flow more freely toward the flash during the forging process is called an unrestricted web (Figure 7) 2.4 Restricted web (closed web)
The web that is completely surrounded by ribs, or although not completely surrounded, has a smaller opening, is called a restricted web (Figure 8). 3 Structural elements
3.1 Groove fillet radius of contraction section, multi-step section, gear spoke, and crankshaft Contraction section [Figure la)], multi-step section [ Figure 1b], gear spokes [Figure 1c], crankshaft [Figure 1d], the minimum inner and outer groove radius r^, according to the height of the boss, respectively refer to Table 1 and Table 2 to determine, State Machinery Industry Bureau approved 1999-06-24 338
2000-01-01 implementation
Height of the boss
JB/T91771999
Table 1 Inner groove radius r
Maximum diameter or height of forgings
Note: The values ​​in brackets are not used as much as possible due to the high technical cost. 63
18(10)
16(10)
20(12)
18(12)
22(11)
28(16)
16(10)
20(14)
25(16)
32(18)
16(10)
20(12)
25(16)
32(18)
Height of shoulder
JB/T91771999
Table 2 External groove radius
Maximum diameter or height of forging
18(10)
Note: The values ​​in brackets are not used as much as possible due to higher technical costs. 3.2
Minimum bottom thickness
20(12)
25(16)
The minimum bottom thickness dimension Ss (Fig. 2) is determined by referring to Table 3 for diameter and width. Table 3 Minimum bottom thickness SB
Rotationally symmetric
Diameter d
16(11)
22(16)
32(22)
Width b4
18(16)
22(14)
28(18)
36(22)
Asymmetrical
2.5(1.5)2.5(1.5)
Note: The data in brackets are not used as much as possible due to the high technical cost. da
dr= Vd-
20 (12) ||tt | )
18(13)bzxz.net
20(12)
25(16)
32(20)
40(25)
63(32)
16(11)
22(16)
22(16)
25(18)
32(22)
3.3 Minimum wall thickness, rib width and rib end fillet radius JB/T 9177-1999
Figure 2 (End)
d, - Vk, -ds
The minimum wall thickness SW, rib width SR and rib end fillet radius 7xk (Figure 3) shall be determined by referring to Table 4 according to the wall height hw and rib height hs. )
JB/T91771999
Table 4 Minimum wall thickness Sw, rib width SR and rib end fillet radius rRK Wall height or rib height (hw or h)
Note: The data in brackets are not used as much as possible due to the high technical cost. 3.4 Minimum punching diameter, blind hole and skin thickness 3.4.1 The minimum punching diameter of forgings is 20mm (Figure 4). Wall thickness
20(12)
32(20)
20(12)
Deepness of one-way blind hole: When L=B, II/B≤0.7: When L>B,,H/B≤1.0 (Figure 5). 3.4.2
3.4.3 Depth of two-way blind hole: Determined according to the one-way sound hole (Figure 6). 3.4.4 Continuous skin thickness
The continuous skin thickness shall not be less than the minimum web thickness t2. See Table 5 and Figure 8. 3.5 Minimum web thickness
The minimum web thickness shall be determined by referring to Table 5 (Figures 7 and 8) based on the projected area of ​​the forging on the parting surface. 342
Radius of fillet at rib end
10（6)
Projected area of ​​forging on parting surface
>25～50
>50～100
>100～200
200～400
>400～800
>800～1000
≥1 000～1250
≥1 250～1 600
>1 600～2 000
>2 000～2500
JB/T 91771999
Table 5 Minimum thickness of web
Unrestricted web
Note: The t and t in the table are allowed to be changed according to the equipment and process conditions. Restricted web
4 Forging dimension marking and measurement method
JB/T9177—1999
Dimension marking and measurement method perpendicular to the parting surface 4.1
Dimensions of forgings perpendicular to the parting surface, their marking and measurement methods are the same as those of general parts. 4.2 Dimension marking and measurement method parallel to the parting surface Unless otherwise specified, the dimensions of the forging parallel to the parting surface shall be marked according to the theoretical intersection (Figure 9). The position of this intersection on the forging is determined by moving a distance (×r). The coefficient table values ​​are determined according to Table 6, where α or β is the die forging slope (measured in angle). 0
α or β
1°00m
1°30″
10°00
12°001
15°00
Table 6 Coefficient value table
or 6=B+90°
α+90°
Note, k=1-i-cote,
where 9=
A is enlarged
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.