1、This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 by Navistar, Inc. AUGUST 2009 Page 1 of 5 NAVISTAR, INC. Engineering Standard Parts NUMBER: ESP-CM-1
2、.101-GS TITLE: Machine Screws General Specifications Metric Series - (Noun Code 7450) CURRENT ISSUE DATE: August 2009 WRITTEN/REVIEWED BY: Corporate Technical Standards APPROVED BY: Corporate Technical Standards SUPERSEDES ISSUE OF: May 2007 PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CURRE
3、NT REVISION Change Notice: Added reference to the German Institute of Standardization standard 7985. Replaced International Truck and Engine Corporation with Navistar, Inc. per corporate directive. GENERAL: For purposes of this standard, the generic term “machine screws“ has been adopted as applying
4、 to products normally threaded to the head in smaller nominal sizes and made of low carbon steel. This specification contains the essentials of the following standards: International Organization for Standardization: ISO 898/1, 965/2, 4757, 7045, 7046, 7047, 7721 British Standards Institute: BS 4183
5、 German Institute of Standardization: DIN 965, 966, 7985 American Society of Mechanical Engineers: B18.6.7M The inclusion of dimensional data is not intended to imply that all the screws described are stock production sizes. Inch dimensioned standard machine screws may be found in ESP-C-1.101-GS. PR
6、EFERRED PARTS POLICY: Preferred parts are so designated to reduce variety of parts and assure maximum availability, interchangeability, and cost savings. Material: Class 4.8 Finish: Zinc Trivalent (ZN6A) and Phosphate Coating (PHC) Nominal Sizes and Lengths: See table following. Copyright Navistar I
7、nternational Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-CM-1.101-GS TITLE: Machine Screws General Specifications CURRENT ISSUE DATE: August 2009 This document is restricted and may not be sent ou
8、tside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 by Navistar, Inc. AUGUST 2009 Page 2 of 5 Dimensions in millimeters: Nominal Screw Length Nominal Screw Size M3 M3.5 M4 M5 M6 M8 M10 M12* 5 x x 6 x x
9、x 8 x x x x x 10 x x x x x x 12 x x x x x x x 14 x x x x x x x 16 x x x x x x x 20 x x x x x x x 25 x x x x x x x x 30 x x x x x x x x 35 x x x x x x x 40 x x x x x x 45 x x x x x 50 x x x x x 55 x x x x 60 x x x x 65 x x x 70 x x x 75 x x x 80 x x x 85 x x 90 x x 100 x x 110 x 120 x * Hexagon washe
10、r head machine screws only. Heavy top line is first length for countersunk screws. Dotted line is first length for headed screws. BEARING SURFACE: The bearing surface of flat bearing surface type machine screw heads will be at right angles to the axis of the screw shank within two (2) degrees. ECCEN
11、TRICITY: Heads will not be eccentric with the machine screw bodies by more than three percent of the maximum head diameters or the maximum width across flats. Recess will not be eccentric with machine screw bodies by more than six percent of the maximum body diameter or 0.25 mm whichever is greater.
12、 Eccentricity is defined as one-half of the full indicator movement (FIM). GEOMETRY OF HEXAGON HEADS: The dimensions across the flats of the head will be measured at the point of maximum material, and the taper of the sides of the hexagon (the angle between one side and the axis) will not exceed two
13、 (2) degrees. A slight rounding of all edges and corners of the hexagon surfaces is permissible. For heads formed with an integral washer, the radius at the junction of the sides of the hexagon and the top surface of the washer will not exceed the values given in ESP-CM-8.101-PP. Copyright Navistar
14、International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-CM-1.101-GS TITLE: Machine Screws General Specifications CURRENT ISSUE DATE: August 2009 This document is restricted and may not be sent o
15、utside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 by Navistar, Inc. AUGUST 2009 Page 3 of 5 GAGING FOR LACK OF FILL: The rounding due to lack of fill on all six corners of the hexagon will be reasona
16、bly uniform. The dimension across the corners of the head will be such that it will be accepted by a ring gage as shown in ESP-CM-8.101-PP. The ring gage will be placed on the top only for hexagon washer head screws, and the head will protrude by an amount equal to or greater than the value given in
17、 ESP-CM-8.101-PP. DEPTH OF RECESS: The depth of recess will be measured parallel to the axis of the screw for the intersection of the maximum diameter of the recess with the head surface to the bottom of the recess. Recess penetrating gauging depth values are included in the dimensional tables and t
18、he method of gaging and specifications for gages will be in accordance with ISO 4757. TOLERANCE ON LENGTH: The length of screw will be measured, parallel to the axis of screw, from the extreme point to the plane of the bearing surface for screws having flat bearing surface type heads, and to the int
19、ersection of the top surface of head with the head diameter for screws having countersunk-type heads. Nominal Screw Length Tolerance on Length, mm Up to 3 mm, inclusive +/- 0.2 Over 3 to10mm , inclusive +/- 0.3 Over 10 to 16 mm, inclusive +/- 0.4 Over 16 to 50mm, inclusive +/- 0.5 Over 50 mm +/- 1.0
20、 THREADS: Thread form, diameters, and associated pitches are in accordance with ISO recommendations for coarse pitch series. Threads will be made to the tolerances of the medium class of fit (6g) external threads for plain or unplated screws as shown in ISO 965/2 - General Purpose Metric Screw Threa
21、ds. LENGTH OF THREAD: For screws having nominal lengths equal to or shorter than listed in Column “L“ of the table following, the full thread will extend close to the head within limits specified in Column “A.“ Screws of longer nominal lengths will have a minimum length of full-formed threads as spe
22、cified in Column “B.“ Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-CM-1.101-GS TITLE: Machine Screws General Specifications CURRENT ISSUE DATE: August 2009 This doc
23、ument is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 by Navistar, Inc. AUGUST 2009 Page 4 of 5 Tolerance of Length Dimensions in millimeters: Nominal Size L A Ma
24、x Unthreaded Length Under Head B Min Full Form Thread Length Nominal Length M3 30 1 25 M3.5 50 1.2 38 M4 50 1.4 38 M5 50 1.6 38 M6 50 2 38 MS 50 2.5 38 M10 50 3 38 BODY DIAMETER: The diameter of the body of machine screws will be within the limits specified in the table below: Dimensions in millimet
25、ers: Nominal Body Diameter Screw Size and Thread Pitch Max Min M3 x 0.5 3 2.58 M3.5 x 0.6 3.5 3.00 M4 x 0.7 4 3.43 M5 x 0.8 5 4.36 M6 x 1 6 5.25 M8 x 1.25 8 7.04 M10 x 1.5 10 8.86 M12 x 1.75 12 10.68 ENDS OF SCREWS: When screws are made with rolled threads, the lead formed at the end of the screw by
26、 the rolling operation will be regarded as providing the necessary chamfer, no other machining operation being necessary, and the end will be reasonably square with the axis of the screw threads. The first two threads will not be full threads and should not be used for load-carrying purposes. When s
27、crews are made with cut threads, the ends will be finished with a (nominal) 45 degree chamfer, the depth slightly exceeding the depth of thread. MATERIAL AND MECHANICAL PROPERTIES: Steel machine screws will be manufactured to ISO Class 4.8 with the characteristics listed in the following table. 5.8
28、material is acceptable ISO ISO Required Characteristics Class 4.8 Class 5.8 * Tensile Strength, min MPa 420 520 (psi) 60 900 75 400 Hardness, min (Rockwell) B71 B82 max (Rockwell) B95 B95 Stress Under Proof Load, MPa* 310 380 (psi) 45 000 55 100 * Acceptable alternate material. * * Allowable permane
29、nt extension will be 12.5 micrometer. Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-CM-1.101-GS TITLE: Machine Screws General Specifications CURRENT ISSUE DATE: Augu
30、st 2009 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2009 by Navistar, Inc. AUGUST 2009 Page 5 of 5 NON-PREFERRED MATERIAL: Material Code Material Typ
31、e Material Specification Remarks SST-304* Stainless Steel, Type 18-8 CEMS A-37 Used for decorative exterior applications. Excellent corrosion resistance. Nonmagnetic. SST-410* Stainless Steel, Type 410 CEMS A-37 Higher strength/hardness obtained through heat treatment. Moderate corrosion resistance.
32、 Magnetic. * Stainless steels will be passivated per ESP-A-1.301. FINISHES: Screws will be furnished plain, plated or coated in accordance with the International Engineering Material Specification and class listed below: Zinc Trivalent on steel (ZN6A) - CEMS G-20, Class 6A. Phosphate Coating (PHC) -
33、 CEMS G-1, Class B2. Black Oxide (BLO) - Standard with Manufacturer. RESTRICTED CHEMICAL SUBSTANCES: Effective January 1, 2007, all product supplied to the requirements of this specification must comply with the requirements of the CEMS B-50 specification. WORKMANSHIP: Screws will be free from burrs, slivers and seams which might affect their serviceability. Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
