1、The Engineering Society SURFACE VEHICLE IhA =For Advancing Mobility -Land Sea Air and SiDace, /NTENAT/ONLw STANDARD 400 Commonwealth Drive, Warrendale, PA 15096-0001 Submitted for recognition as an American National Standard Metric Thread Rolling Screws I =J1237 Issued 1978-06 Revised 2001 -03 Super
2、seding JI237 AUGI 996 foreword-This document has also changed to comply with the SAE Technical Standards Board format. The footnotes in the tables are listed consecutively. i. Scope-This SAE Standard covers requirements for metric thread rolling screws suitable for use in general engineering applica
3、tions. 1 .I Requirements for three material-process options are stated: a. Screws (in sizes M2 x 0.4 thru MI2 x 1.75) manufactured from low carbon steel, carburized, and tempered. These screws are designated SAE JI237 Type 2 0. b. Screws (in sizes M2 x 0.4 thru MI2 x 1.75) manufactured from medium c
4、arbon alloy steel, heat treated to achieve properties comparable to SAE JI199 class 9.8 screws, and additionally, with the point selectively hardened. These screws are designated SAE JI237 Type 9 0. c. Screws (in sizes M5 x 0.8 thru MI2 x 1.75) manufactured from medium carbon alloy steel, heat treat
5、ed to achieve properties comparable to SAE JI199 class 10.9 screws, and additionally, with the point selectively hardened. These screws are designated SAE JI237 Type 10 0. 1.2 When SAE JI237 is specified without Type designation, either Type 2 or Type 9 may be supplied. NOTE-The performance requirem
6、ents covered in this document apply only to the combination of laboratory conditions described in the testing procedures. If other conditions are encountered in an actual service application (such as different materials, thicknesses, hole sizes, etc.), values shown herein for drive torque, torque-to
7、-clamp load, and proof torque may require adjustment. 2. References 2.1 Applicable Publications-The following publications form a part of this specification to the extent specified herein. Unless otherwise specified, the latest issue of SAE publications shall apply. 2.1 .I SAE PUBLICATIONS-Available
8、 from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001. SAE J121-Decarburization in Hardened and Tempered Unified Threaded Fasteners SAE J423-Methods of Measuring Case Depth SAE J864-Surface Hardness Testing and Files SAE JI 199-Mechanical and Material Requirements for Metric Externally Thread
9、ed Steel Fasteners SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringem
10、ent arising therefrom, is the sole responsibility of the user.“ SAE reviews each technical report at least every five years at which time it may be reaffirmed, revised, or cancelled. SAE invites your written comments and suggestions TO PLACE A DOCUMENT ORDER: +I (724) 776-4970 FAX: +I (724) 776-0790
11、 SAE WEB ADDRESS http:/www.sae.org Copyright 2001 Society of Automotive Engineers, Inc. All rights reserved. Printed in U.S.A. Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE JI237 Revised MAR200
12、1 2.1.2 ASTM PUBLICATION-Available from ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959. ASTM F 606M-Standard Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners, Washers, and Rivets 2.1.3 MILITARY DOCUMENT-Available from DODSSP, Subsc
13、ription Services Desk, Building 4D, 700 Robbins Avenue, Philadelphia, PA 191 11-5094. MIL-STD-105D 3. Requirements 3.1 3.1.1 Material and Process Requirements-Type 2 MATERIAL AND CHEMISTRY-Type 2 screws shall be made from cold heading quality, killed steel wire conforming to the chemical composition
14、 requirements in Table 1 : TABLE I-TYPE 2 -CHEMICAL COMPOSITION REQUIREMENTS- COMPOSITION LIMITS(), % BY MASS Carbon Carbon Manganese Manganese Analysis Min Max Min Max Cast or Heat 0.15 0.25 0.70 1.65 Product 0.13 0.27 0.64 1.71 1. Boron permitted in the range of 0.0005 to 0.003. 3.1.2 HEAT TREATME
15、NT-Type 2 screws shall be heat treated in a continuous carbonitriding or gas carburizing system. Cyaniding systems may be approved by the purchaser when it is shown that a continuous flow (no batch) quenching process which consistently produces uniform case and core hardnesses is employed. TEMPERING
16、 TEMPERATURES-MinimUm tempering temperatures shall be 340 “C. 3.1.3 3.2 3.2.1 Material and Process Requirements-Types 9 and 1 O MATERIAL AND CHEMISTRY-Unless otherwise specified by purchaser, Type 9 and 10 screws shall be made from cold heading quality, killed alloy steel wire conforming to the chem
17、ical composition requirements (SAE 4037) in Table 2: TABLE 2-TYPES 9 AND 10 -CHEMICAL COMPOSITION REQUIREMENTS Cast or Heat Analysis % by Mass Product Analysis % by Mass Carbon Manganese Phosphorus Sulfur Silicon Molvbdenum 0.35-0.40 O. 70-0.90 0.035 max 0.040 max O. 15-0.30 0.20-0.30 0.33-0.42 0.67
18、-0.93 0.040 max 0.045 max 0.1 3-0.32 0.1 8-0.32 3.2.2 HEAT TREATMENT-Type 9 and 10 screws shall be heat treated in a continuous non-carburizing system operated under fine grain practice, oil quenched, and tempered at a minimum tempering temperature of 460 “C for Type 9 and 425 “C for Type 1 O 0. -2-
19、 Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE JI237 Revised MAR2001 3.2.3 Lead threads on type 9 and 10 shall be induction hardened to achieve a minimum hardness equivalent to 45 RC (Rockwell
20、C45) on 1 to 3 full threads and one or more lead threads, as shown in Figure 1. (File test according to SAE J864.) 2 to 3-1 /2 PITCH TAPER LENGTH I I- 0.2 mm BELOW ROOT OF 1- MAX M* = REQUIRED HARDENED AREA SHALL ENCOM- PASS FIRST FULL THREAD = PERMISSIBLE HARDENED AND TRANSI- TION ZONE MAY EXTEND T
21、O ENCOMPASS SECOND AND THIRD FULL FORM THREAD NOTE TO USER-Wen rlecting Iongth of Typ. 9 o and 10 o scmw for my application, one objective should be location of the induction hardened zone beyond the nut anchorage, or a minimum of six full form threads in the threaded hole. FIGURE I-INDUCTION HARDEN
22、ED LEAD THREADS 3.3 Finish-Screws shall be cadmium or zinc electroplated with a coating thickness of 5 to 10 pm, or have a zinc phosphate and oil coating as specified by the purchaser. Unless otherwise specified, screws may be provided with an additional supplementary lubricant as necessary to meet
23、the performance requirements. Other finishes are available, however, and it is the intent of this document that the mechanical and performance requirements shall apply only to those screws having one of the three finishes specified previously. When other finishes are required, the purchaser and manu
24、facturer may agree on performance values other than those of 3.7. Electroplated screws shall be baked within the temperature range 190 to 230 “C within 1 h after plating to avoid hydrogen embrittlement. Parts must be maintained at temperature for 4 h. In cases where screws are plated or coated follo
25、wing delivery to the purchaser (or where plating or coating of screws is otherwise under the control of the purchaser) the screw producer shall not be responsible for failures of the screw to meet mechanical or performance requirements due to plating or coating. 3.4 Dimensional Requirements 3.4.1 HE
26、AD DIMENSIONS-Standard head styles for thread rolling screws are flat countersunk, oval countersunk, pan, hex, hex washer, and hex flange head. Flat countersunk, oval countersunk, and pan head screws are available slotted or with Type 1 or Type IA cross recess drives. Head, slot, and cross recess di
27、mensions shall be specified by purchaser. -3- Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE JI237 Revised MAR2001 3.4.2 THREAD AND POINT DIMENSIONS-Thread and point dimensions shall conform to
28、those given in Table 3. Threads shall conform to a 60-degree basic thread form. Threads are not subject to thread gaging. Details of point configuration shall be optional with the manufacturer providing all specified dimensions are maintained and screws meet the performance requirements of this docu
29、ment. TABLE 3-THREAD AND POINT DIMENSIONS OF THREAD ROLLING SCREWS() L L Min Practical Nominal C CP Min Practical Nominal Screw P Dia of Circumscribing Nominal Screw Length and Major Point Circumscribing Circle Point Point Screw Length Flat and Thread Dia(2) Dia(2) (Point)(3) Length Length Pan, Hex,
30、 Oval Ctsk Pitch Max Max Max Max Max(4) Mid5) Hex Washer Heads Heads - 1.4 0.8 4 M2.5 x0.45 2.50 2.1 2.57 2.13 1.6 0.9 4 M3 x0.5 3.00 2.5 3.07 2.58 1.8 1 .o 5 M2 x0.4 2.00 1.6 - M3.5 x0.6 3.50 2.9 3.58 2.99 2.1 1.2 6 M4 x0.7 4.00 3.4 4.08 3.40 2.4 1.4 8 M5 x0.8 5.00 4.4 5.09 4.31 2.8 1.6 8 M6x1 6.00
31、 5.3 6.10 5.12 3.5 2.0 10 5 6 8 8 10 10 12 M8 x 1.25 8.00 7.1 8.13 6.92 4.4 2.5 10 16 M10x1.5 10.00 9.0 10.15 8.69 5.2 3.0 13 16 M12x 1.75 12.00 10.5 12.18 10.48 6.1 3.5 16 20 1. 2. 3. 4. 5. 3.4.3 All dimensions are millimeters. These dimensions are applicable to types of screws where periphery of t
32、he thread approximates a circle. These dimensions are applicable to types of screws where some portions of the periphery of the thread are farther from the screw axis than others (lobular, triroundular, etc.). These values are equal to 3.5 times the pitch distance rounded off to 1 decimal place. The
33、se values are equal to 2 times the pitch distance rounded off to 1 decimal place. THREAD LENGTH-FOT screws of nominal lengths within the ranges listed under column Y of Table 4, the full form threads shall extend close to the head such that the specified thread major diameter limits are maintained t
34、o within the respective Y distance from the underside of the head, or closer if practicable. See Figure 2. Screws of longer nominal lengths, unless otherwise specified by the purchaser, shall lave a minimum length of full form thread as specified in column LT. t-ty FIGURE 2-UNTHREADED LENGTH -4- Cop
35、yright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SAE JI237 Revised MAR2001 TABLE 4-FULL FORM THREAD LENGTH AND UNTHREADED LENGTHS() LT Full Form Thread Nominal Length Screw for Size Nominal and Screw Thr
36、ead Lengths Pitch Than Y Unthreaded Length Under Head LT for Full Form Nominal Thread Screw Length Lengths Mid2) CThan Y Unthreaded Length Under Head Y for Unthreaded Nominal Length Screw Under Head Lengths Max(3) Than Y Unthreaded Length Under Head for Y Nominal Unthreaded Screw Length Lengths Unde
37、r Head Than Max(4) M2 x 0.4 M2.5 x 0.45 M3 x 0.5 M3.5 x 0.6 M4 x 0.7 M5 x 0.8 M6x1 M8 x 1.25 MI0 x 1.5 MI2 x 1.75 16 20 25 30 35 40 45 45 45 50 12.0 15.0 18.0 21 .o 24.0 30.0 38.0 38.0 38.0 38.0 6 8 9 10 12 15 18 24 30 36 0.40 0.45 0.50 0.60 0.70 0.80 1 .o0 1.25 1.50 1.75 6 8 9 10 12 15 18 24 30 36
38、16 20 25 30 35 40 45 45 45 50 0.8 0.9 1 .o 1.2 1.4 1.6 2.0 2.5 3.0 3.5 1. All dimensions are millimeters. 2. Tabulated values through 5 mm size are equal to 6 times basic screw diameter rounded to nearest millimeter. 3. Tabulated values are equal to 1 times thread pitch. 4. Tabulated values are equa
39、l to 2 times thread pitch. 3.5 Mechanical Requirements-Type 2 Screws 3.5.1 HARDNESS 3.5.1.1 3.5.1.2 3.5.1.3 Core Hardness-Type 2 screws shall have a core hardness of 28-38 RC (Rockwell C) when tested as specified in 4.1. Core hardness shall not exceed maximum shown and preferably should be no higher
40、 than 36 RC (Rockwell C) on electroplated parts. Case Hardness-Type 2 screws shall have a case hardness of 45 RC (Rockwell C), minimum, when tested as specified in 4.2. Tofal Case Depfh-Type 2 screws shall have a total case depth conforming to Table 5, when tested as specified in 4.3. TABLE 5-TYPE 2
41、 -TOTAL CASE DEPTH Nominal Size Total Case Total Case Depth, mm Depth, mm Min Max 2 through 3.5 0.05 0.18 4 and 5 0.10 0.23 6 through 12 0.13 0.28 -5- Copyright SAE International Provided by IHS under license with SAENot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
42、SAE JI237 Revised MAR2001 3.5.2 TENSILE STRENGTH-Type 2 screws with hex head, hex washer head, and hex flange head, which have lengths equal to or longer than 12 mm or 3 times the nominal screw diameter, whichever is longer, shall have tensile strengths not less than those specified in Table 6, when
43、 tested in accordance with 4.4. Screws with shorter lengths or screws with other head styles which are weaker than the threaded section are not subject to tensile testing. TABLE 6-MECHANICAL REQUIREMENTS FOR TYPE 2 THREAD ROLLING SCREWS Basic Dia Min Min and Tensile Torsional Thread Pitch Strength S
44、trength (millimeters) kN N.m M2 x 0.4 1.9 0.7 M2.5 x 0.45 3.15 1.2 M3 x 0.5 4.68 2.2 M3.5 x 0.6 6.3 3.5 M4 x 0.7 8.17 5.2 M5 x 0.8 13.2 10.5 M6x1 18.7 17.7 M8 x 1.25 34.0 43.0 MI0 x 1.5 53.9 87.0 MI2 x 1.75 78.4 152.0 3.5.3 TORSIONAL STRENGTH-Type 2 screws shall not fail with the application of a to
45、rque less than the torsional strength torque specified in Table 6 when tested in accordance with 4.5. 3.5.4 DUCTILITY-Heads of screws shall not separate from the shank when a permanent deformation of 7 degrees is induced between the plane of the under head bearing surface and a plane normal to the a
46、xis of the screw, when tested in accordance with 4.8. 3.6 Mechanical Requirements-Type 9 and 10 Screws 3.6.1 I Type 9 and 10 screws shall conform to the mechanical requirements specified in Table 7 when tested according to wedge tensile and hardness procedures published in ASTM F 606M. TABLE 7-MECHA
47、NICAL REQUIREMENTS TYPE 9 AND 10 SCREWS Wedge Tensile Strength (Stress) Surface Hardness Product Hardness Type MPa(1)(2) Rockwell 15N, max Rckwell() 9. 900 min (4) C27-36 10 . 1040 min (4) c33-39 1. Wedge tensile strength values for full size products are specified in Table 8. Wedge tensile strength
48、s are applicable only to screws which have lengths equal to or longer than 12 mm or 3 times the nominal diame- ter, whichever is longer. Screws with shorter lengths or screws with head styles which are weaker than the threaded section are not subject to wedge tensile testing. 2. Tensile wedge angles
49、: 6 degrees when screws are threaded one diameter or closer to the head; 10 degrees on all others. 3. Minimum product hardness values applicable to screws not subject to tensile tests, and these hardness requirements exclude induction hardened zone 3.2.3 (Figure 1). 4. Surface hardness shall not exceed product hardness by more 3 points Rockwell C equivalent, and in the case of Type 10 shall also not exceed Rockwell 15N 80, except as noted in 3.2.3 (Figure 1). -6- Copyright S
