1、 ENGINEERING STANDARDS Test Procedure SUPERCEDED EDS-T-7150 Method of Decarburized Depth Measurement for Bolt This standard may be applied only for current projects. It is Superceded for all future projects and replaced by ISO 898-1. .0C8 AA?i 8 4G - Note: 8 E:48t G8 =97 FF7 957%L+ , FG P-P Program
2、.Bd# ISO 898-1 ) $4=F7 957F$ . Copyright 2011 General Motors Company All Rights Reserved July 2011 Originating Department: GM Korea Engineering Standards Page 1 of 5 Version : 4 1 Scope Note: Nothing in this standard supersedes applicable laws and regulations. Note: In the event of conflict between
3、the Korean and English language, the Korean language shall take precedence. 1.1 Purpose. This standard aims at evaluating the product quality by measuring the decarburized depth of thread deteriorating the fastening force which is the major function of the bolt and influencing the fatigue strength.
4、1.2 Applicability. This standard specifies the decarburized depth measurement for external thread parts such as bolts and machine screws. This standard shall apply mainly to the mechanical strength class 8.8 or more of the external thread parts. 2 References Note: Only the latest approved standards
5、are applicable unless otherwise specified. 2.1 External Standards/Specifications. ISO 898/1 ISO 6507 KS B 0201 KS B 0204 KS B 0233 2.2 GM Standards/Specifications. None 2.3 Additional References. None 3 Resources 3.1 Test Piece. 3.1.1 Test piece shall be manufactured by fixing the external thread pa
6、rts to the attachment position by a clamp, fixing to the mount of the thermosetting plastics (bakelite or phenol powder) or molding by a epoxy resin. 1 P7 :0 : ., E:48 6&F !7$ :4-8! 9I8x $4=F 3L 6$ . :0 : F67t 7568 18 88x 7 , F6* 72T8p) F$ . 1.1 +95 . 8 8t .0C8 :07d#8 =)Y8x 94F4A+ Fp)I$7 75F8x -,?#
7、!1.8 AA?i 8* ?U9IF8p)4 , 9PE8 E:8x D4Fd 88F8$ . 1.2 957-88 . 8 E:48t .0C! 88t !1 &% 3L!1 .E8 !1. AA?i 8 ?U9I4G 7 957F$ . $ 3L!1 .E8 d95 I$ .8t 8.8 &%= 817 957F$ . 2 4) E:4 / :0 : C-H +d%P 9I8 6# F 48 07 38%P E:48x 957F$ . 2.1 17 E:4 / . ISO 898/1 ISO 6507 KS B 0201 KS B 0204 KS B 0233 2.2 GM E:4 / .
8、 None 2.3 dA E:4 / . None 3 4G 88 3.1 4G D . 3.1.1 4G D 9P88t 3L!1 .E8x .=.7 A(F8 D# 7( G2e F(3D%9P (-8A (8C D# D“ D7$ ) *7C) 9IF$ . Gl*8?* 87F7 +& (Molding)F7 $ %P$ . GM KOREA ENGINEERING STANDARDS EDS-T-7150 Copyright 2011 General Motors Company All Rights Reserved July 2011 Page 2 of 5 Version :
9、4 3.1.2 The thread part of the fixed external thread parts shall be sectioned in longitudinal direction so that the axis is included. At this time, it shall be cautious not to be discolored for the sectioned surface due to friction heat. 3.1.2 9I%P 3L!1 .E8 !1.* 4 8 E F%L$) l8-F8p) 92 3P 81 , 3L8 17
10、8p)# 2 1P 818 4G D8x 4G F6 F$ . 4 4G 92F8x +9F6 F$ . Figure 2: Hardness Measuring Points Examining Height of Non-decarburized Area / ,* 2: /xAA.8 “8* 91F# $8 ?U9I9D Remark: H1 is the thread height(f) of external thread, E is the maximum height of non-decarburized area and the values of H, and E(mini
11、mum) at pitch of 0.5 ) 4 shall be indicated in Table 1. Note 2: Cut height of underroot of external thread shall be H/6. Here, H = 0.866025P. / /x : ,* 37 862P H18t 3L!18 $4 4=7 862P8 !118 “8 (1)8+ , E# /xAA.8 “8 (2 )8 , Fp? (P)4 0.5 - 4mm7 862P H1 -C E(2 )F8x E 17 E4F74$ . :0 2: 3L!1 -E8 92 )8 F Sc
12、rew Pitch (P) / !18 Fp? (P) 0.5 0.6 0.7 0.8 1 1.25 1.5 H1 0.307 0.368 0.429 0.491 0.613 0.767 0.920 E Strength / I$ . 8.8 9.8 0.154 0.184 0.215 0.245 0.307 0.384 0.460 10.9 0.205 0.245 0.286 0.327 0.409 0.511 0.613 12.9 0.230 0.276 0.322 0.368 0.460 0.575 0.690 GM KOREA ENGINEERING STANDARDS EDS-T-7
13、150 Copyright 2011 General Motors Company All Rights Reserved July 2011 Page 4 of 5 Version : 4 Screw Pitch (P) / !18 Fp? (P) 1.75 2 2.5 3 3.5 4 H1 1.074 1.227 1.534 1.840 2.147 2.454 E Strength / I$ . 8.8 9.8 0.537 0.614 0.767 0.920 1.074 1.227 10.9 0.716 0.818 1.023 1.227 1.431 1.636 12.9 0.806 0.
14、920 1.151 1.380 1.610 1.841 5 Data 5.1 Evaluations. The measured value of total decarburized depth (G) and height (E) of non-decarburized height (E) shall meet the value specified in the drawing or related standard (material standard). 5.2 Indication. For the total decarburized depth (G) and height
15、(E) of non-decarburized area, the mean value measured at 3 or more portions shall be recorded. 6 Safety This standard may involve hazardous materials, operations, and equipment. This standard does not propose to address all the safety problems associated with its use. It is the responsibility of the
16、 user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. 7 Notes 7.1 Glossary. Decarburized Layer: The surface layer(including thread part) where the carbon content is reduced in comparison with base metal by
17、hot working or heat treating. Partial Decarburized Depth: Distance from the surface of the decarburized depth to the position where the difference in chemical (structure) or physical properties (hardness) between the decarburized depth and the base metal is no longer determinable (I of Figure 3). To
18、tal Decarburized Depth: Distance from the surface to the position where is made of structure having different property from the base structure, i.e ferrite formed by decarburization (G of Figure 3). Specific Residual Carbon Ratio Decarburized Depth: Decarburization depth specified by residual carbon
19、 ratio Distance from the surface to the position where the residual carbon ratio has a specified value (the residual carbon ratio per carbon content of the base metal). 5 4G $8Bd 5.1 D4 . 98 AA?i 8 (G) -C /x AA.8 “8 (E)8 ?U9IF8t $+ D# 4) (8: )7 9I%P F8x +9F6 F$ . 5.2 E4 . 98 AA?i 8 (G) -C /x AA.8 “8
20、 (E)# 3.88 81 ?U9IF7 DF8x d8F$ . 6 6|987 $4F 7 9 ., E:48t 88G ,p: , 86 , 8/x &%8x E FF 3L 8$ . ., E:48t 87 $4F 170 4)%P +& 6|98 ,l9P8 F8x 9P4F:# 6#$ . &d(2P 17 987 95FF 6|980 I 1B* 9DF , -18 9PF 728 957 7 .* 9IF# 8t ., E:4 1788 =y8 1F8$ . 7 768 9I8 7.1 98,l 76 . AA?i : 288 7(8 4)4! .0C8 989 G 7(=*4
21、, E?i. (!1. E F )8 A2 “$4 2: 8 “$.($ D2%P . . . AA?i : AA?i E+8p).Bd AA?i0 2:$4 4=7 862P8 18 “8 H1 -C E(2 ) F8t E 1 =l9 . 7.2 Acronyms, Abbreviations, and Symbols. Not applicable. 8 Coding System This standard shall be referenced in other documents, drawings, etc., as follows: Test to EDS-T-7150 9 R
22、elease and Revisions This standard was originated in April 1994. It was first approved by Engineering Standard Committee in April 1994. It was first published in April 1994. 7.2 66 -C dGl . F$-1F 68 . 8 Ed - $* ,l2P! $+ &%72P ., E:48 87%T &# $80 M8 EdF$ . Test to EDS-T-7150 9 9P9I -C P9I 8)Y ., E:48
23、t 1994 “x 4 87 E:4 -Gl4 .7 %L6 , d3TE:41,h7 8F 1994“x 487 38%L6$ . ., E:48t 1994“x 487 ) 9P9I / -PF%L6$ . Issue / P9I8)Y Publication Date / 38 88 Description (Organization) / 9PP9I76 (:04.2P ) 4 JUL 2011 Apply new Engineering Standard Template. Superceded (Corrosion / Metallurgical Material Lab Team) / 4 d3TE:4 64 957 . F9I957 =* (28*4G D4 )
