1、INTERNATIONAL TRUCK AND ENGINE CORPORATION Engineering Standard Parts NUMBER: ESP-C-1.101-GS TITLE: Machine Screws General Specifications (Noun Code 7450) CURRENT ISSUE DATE: May 2007 WRITTEN/REVIEWED BY: Corporate Technical Standards APPROVED BY: Corporate Technical StandardsSUPERSEDES ISSUE OF: Ja
2、nuary 2006PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CURRENT REVISION Change Notice: Changed 304-SST to SST-304. Changed 410-SST to SST-410. Removed Cadmium (CAD) finish option. Removed Cadmium with Chromate (CDD) finish option. Replaced Zinc with Chromate (ZND) finish option with Zinc Tri
3、valent, Class 6A, (ZN6A) finish option. GENERAL: This standard conforms essentially with the American National Standard B-18.6.3 for various types of slotted and recessed head machine screws. Truss Head, Round Head and Binding Head Machine Screws are not preferred for new design and should be replac
4、ed in new design by Pan Head Machine Screws. PREFERRED PARTS POLICY: Preferred parts are so designated to reduce variety of parts and assure maximum availability, interchangeability and cost savings in volume buying. Head Types: Flat, Oval, Pan, Hex Drive: Cross Recess, ANSI Type 1, (Phillips), and
5、Hex Diameters: 6, 8, 10, 1/4, 5/16, 3/8 Threads: Coarse Finishes: Zinc with Chromate (ZND), Phosphate Coated (PHC) Lengths: As shown below: SERVICE PARTS SUBSTITUTION POLICY: In the event that engineering does not indicate a “Do not substitute“ in engineering specifications, the following substituti
6、ons may be implemented in service. This policy is the result of a proposal circulated April 20, 1981, and subsequently approved by engineering departments worldwide. This document is restricted and may not be sent outside International Truck and Engine Corporation or reproduced without permission fr
7、om Corporate Technical Standards. Suppliers are required to assume all patent liability. 2007 by International Truck and Engine Corporation. MAY 2007 Page 1 of 6 Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitte
8、d without license from IHS-,-,-NUMBER: ESP-C-1.101-GS TITLE: Machine Screws General Specifications CURRENT ISSUE DATE: May 2007 This document is restricted and may not be sent outside International Truck and Engine Corporation or reproduced without permission from Corporate Technical Standards. Supp
9、liers are required to assume all patent liability. 2007 by International Truck and Engine Corporation. MAY 2007 Page 2 of 6 Flat Head Machine Screws To Be Replaced Service ReplacementSlotted or Cross Recess, plain (PLN) finish Zinc with chromate (ZN6A) cross recess or (ZN6A) slotted (if cross recess
10、 is not set up for service. Slotted, phosphate coated (PHC) finish Cross Recess, phosphate coated (PHC) finish Slotted, zinc with chromate (ZN6A) finish Cross Recess, zinc with chromate (ZN6A) finish Pan Head Machine Screws To Be Replaced Service ReplacementSlotted or Cross Recess, plain (PLN) finis
11、h Zinc with chromate (ZN6A) cross recess or (ZN6A) slotted (if cross recess is not set up for service. Slotted, phosphate coated (PHC) finish Cross Recess, phosphate coated (PHC) finish Slotted, zinc with chromate (ZN6A) finish Cross Recess, zinc with chromate (ZN6A) finish Fillister Head Machine Sc
12、rewsTo Be Replaced Service ReplacementSlotted or Cross Recess, plain (PLN) finish Zinc with chromate (ZN6A) cross recess or (ZN6A) slotted (if cross recess is not set up for service. Slotted, zinc with chromate (ZN6A) finish Cross Recess, zinc with chromate (ZN6A) finish Round Head Machine Screws To
13、 Be Replaced Service ReplacementSlotted, plain finish Pan head, cross recess, zinc dichromate (ZN6A) finish or slotted (if cross recess is not set up for service). BEARING SURFACE: The bearing surface of flat bearing surface type machine screw heads will be at right angles to the axis of the screw s
14、hank within 2 degrees. ECCENTRICITY: Heads will not be eccentric with the machine screw bodies by more than 3 percent of the maximum head diameters. Slots will not be eccentric with machine screw bodies by more than 6 percent of the maximum body diameter of .010 inch whichever is greater. Eccentrici
15、ty is defined as one-half of the full indicator movement (FIM). HEAD HEIGHT: All dimensions pertaining to head height specified in the dimensional tables will be measured parallel to the axis of screw and those relating to the top of head will represent a metal to metal measurement. In other words,
16、any truncation of rounded head contours due to the slot or recess will not be considered part of the head height. Total or overall head heights will be measured from the top of the head to the plane of the bearing surface for flat bearing surface type heads, to the plane of the undercut for undercut
17、 countersunk heads, nd to the junction of conical bearing surface with the basic screw diameter for countersunk heads. aHead side heights will be measured from the intersection of the top surface of head with the head diameter to the plane of the bearing surface for flat bearing surface type heads,
18、to the plane of the undercut for undercut countersunk heads, and to the junction of conical bearing surface with the basic crew diameter for countersunk heads. sCopyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted
19、 without license from IHS-,-,-NUMBER: ESP-C-1.101-GS TITLE: Machine Screws General Specifications CURRENT ISSUE DATE: May 2007 This document is restricted and may not be sent outside International Truck and Engine Corporation or reproduced without permission from Corporate Technical Standards. Suppl
20、iers are required to assume all patent liability. 2007 by International Truck and Engine Corporation. MAY 2007 Page 3 of 6 On countersunk heads, the junction of conical bearing surface with the basic screw diameter may not necessarily be the same as the actual junction of head with shank and the hea
21、d height delineating the conical bearing surface is a reference dimension. PROTUSION OF HEAD: Except for the 0 and 1 size undercut heads, suitability of flat head screws for application in countersinks may be determined by checking the “T“ dimension in a protrusion gage. Protrusion gages will have a
22、 hardness of not less than Rockwell C60. Sharpness of gaging edge will be that which is obtained by lapping the hole and the top surface of the gage. Variation in gaging diameter from the value given in the table will require proportional correction of protrusion gaging values. SLOT DEPTH: The depth
23、 of slot in slotted head screws will be measured parallel to the axis of screw from the top of the head to the intersection of the bottom of the slot with the head surface or bearing surface. DEPTH OF RECESS: The depth of recess will be measured parallel to the axis of the screw from the intersectio
24、n of the maximum diameter of the recess with the head surface to the bottom of the recess. Recess penetration gaging depth values are included in the dimensional tables and the method of gaging and specifications for gages are covered in ESP-C-90.101-GS. Nominal Screw Size 0 1/4 thru thru Nominal Sc
25、rew Length 12 3/4 Tolerance on Length Up to 1/2 in, Incl -.02 -.03 Over 1/2 to 1 in, Incl -.03 -.03 Over 1 to 2 in, Incl -.06 -.06 Over 2 in -.09 -.09 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 h
26、aving flat bearing surface type heads, and to the intersection of the top surface of head with the head diameter for screws having countersunk type heads. THREADS: Threads will be Unified Standard, Class 2A, UNC or UNF series or UNRC or UNRF series with radius root, optional with manufacturer. Class
27、 2A limits will apply to plain finish (unplated or uncoated) screws and to plated or coated screws before plating or coating. For screws with additive finish the maximum diameters of Class 2A may be exceeded by the amount of the allowance, that is, the basic diameters (the Class 2A maximum diameters
28、 plus the allowance) will apply to plated or coated screws after plating or coating. The major diameter of plated or coated screws may approach, but will not be less than the Class 2A minimum limit. LENGTH OF THREAD: Sizes No. 5 and Smaller. Screws of nominal lengths equal to 3 diameters and shorter
29、 will have full form threads extending to within one pitch (thread) of the bearing surface of the head, or closer, if practicable. Nominal lengths greater than 3 diameters, up to and including 1-1/8 inch, will have full form threads extending to within two pitches (threads) of the bearing surface of
30、 the head, or closer if Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-C-1.101-GS TITLE: Machine Screws General Specifications CURRENT ISSUE DATE: May 2007 This docum
31、ent is restricted and may not be sent outside International Truck and Engine Corporation or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2007 by International Truck and Engine Corporation. MAY 2007 Page 4 of 6 practicable. S
32、crews of longer normal lengths will, unless otherwise specified, have a minimum length of full form thread of 1.00 inch. Sizes No. 6 and Larger. Screws of nominal lengths equal to 3 diameters and shorter will have full form threads extending to within one pitch (thread) of the bearing surface of the
33、 head, or closer, if practicable. Nominal lengths greater than 3 diameters, up to and including 2 inch, will have full form threads extending to within two pitches (threads) of the bearing surface of the head, or closer if practicable. Screws of longer nominal lengths will, unless otherwise specifie
34、d, have a minimum length of full form thread of 1.50 inch. DIAMETER OF BODY: The diameter of body on machine screws will not be less than the Class 2A thread minimum pitch diameter no greater than the basic major diameter of the thread. MATERIAL: Material Code Material Type Material Specification Re
35、marks CST Carbon steel SAE 1010-1020 BRS Brass, Alloy C36000 CEMS C-3 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 trea
36、tment. Moderate corrosion resistance. Magnetic. * Stainless steels will be passivated per ESP-A-1.301. FINISHES: As designated by part number, screws will be furnished plain, plated or coated in accordance with the INTERNATIONAL CEMS and class listed below: Zinc Trivalent, Class 6A (ZN6A) - G-20, Cl
37、ass 6A. Phosphate Coating (PHC) - G-1, Class B2. Chromium Bright (CRB) - G-19, Part III, Class 3 CRB or Class 5 CRB as dictated by threads per inch. Chromium Dull (CRD) - G-19, Part III, Class 3 CRD or Class 5 CRD as dictated by threads per inch. Nickel Bright (NIB) - G-19, Part III, Class 3 NIB, or
38、 Class 5 NIB as dictated by threads per inch. Nickel Dull (NID) - G-19, Part III, Class 3 NID or Class 5 NID as dictated by threads per inch. Black Enamel (BLE) - Standard with manufacturer. Black Oxide (BLO) - Standard with manufacturer. Blued (BLU) - Standard with manufacturer. SHORT LENGTH SCREWS
39、: As shown in Table 1, Flat or Oval head screws having lengths equal to or less than the length listed will have head undercut by an amount which reduces the head height to 70 percent of “E.” A corresponding reduction will also apply to slotted or recess depths. Radius dimensions shown will also app
40、ly. Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-C-1.101-GS TITLE: Machine Screws General Specifications CURRENT ISSUE DATE: May 2007 This document is restricted an
41、d may not be sent outside International Truck and Engine Corporation or reproduced without permission from TABLE 1 - DIMENSIONS FOR UNDERCUT HEAD Dimensions in inches: E1R1FLAT HEAD OVAL HEAD H1M1H1M1Head Height Radius Slot DepthCross Recess Depth Cross Recess Depth Slot Depth Cross Recess Depth Cro
42、ss Recess Diameter Nominal Size Nominal Screw Length Equal to or Less Than Max Min Max Max Min Max Min Max Min Max Min Max Min Min Max0 1/8 .025 .018 .009 .011 .007 .043 .027 .069 .056 .028 .022 .045 .027 .074 .0611 1/8 .031 .023 .011 .014 .009 .051 .035 .077 .064 .034 .027 .048 .030 .077 .0642 1/8
43、.036 .028 .013 .016 .011 .056 .040 .095 .082 .040 .033 .069 .052 .112 .0993 1/8 .042 .033 .015 .019 .012 .063 .047 .102 .089 .047 .038 .081 .064 .124 .1114 3/16 .047 .038 .017 .022 .014 .078 .062 .117 .103 .053 .043 .094 .077 .136 .1235 3/16 .053 .043 .019 .024 .016 .089 .073 .128 .115 .059 .048 .08
44、5 .061 .158 .1456 3/16 .059 .048 .021 .027 .017 .078 .055 .146 .133 .065 .053 .105 .080 .178 .1658 1/4 .070 .058 .025 .032 .021 .106 .083 .174 .161 .078 .064 .119 .095 .192 .17910 5/16 .081 .068 .028 .037 .024 .121 .098 .189 .176 .090 .074 .137 .113 .209 .19612 3/8 .092 .078 .032 .043 .028 .121 .098
45、 .233 .220 .103 .085 .152 .128 .270 .2571/4 7/16 .107 .092 .038 .050 .032 .136 .113 .250 .237 .119 .098 .173 .148 .290 .2775/16 1/2 .134 .116 .047 .062 .041 .168 .146 .317 .304 .149 .124 .226 .202 .381 .3683/8 9/16 .161 .140 .056 .075 .049 .216 .194 .365 .352 .179 .149 .245 .221 .400 .3877/16 5/8 .1
46、56 .133 .066 .072 .045 .245 .223 .393 .380 .184 .154 .257 .233 .410 .3971/2 3/4 .156 .130 .075 .072 .046 .261 .242 .409 .396 .204 .169 .269 .245 .422 .409POINTS: Machine screws are regularly supplied with a plain sheared end, not pointed. However, for specific applications and under separate part nu
47、mber, screws up to certain lengths may be obtained with header points, see Table 2. Pointing of longer lengths will require machining. Corporate Technical Standards. Suppliers are required to assume all patent liability. 2007 by International Truck and Engine Corporation. MAY 2007 Page 5 of 6 Copyri
48、ght Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-C-1.101-GS TITLE: Machine Screws General Specifications CURRENT ISSUE DATE: May 2007 This document is restricted and may not
49、be sent outside International Truck and Engine Corporation or reproduced without permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2007 by International Truck and Engine Corporation. MAY 2007 Page 6 of 6 TABLE 2 DIMENSIONS FOR HEADER POINTS Dimensions in inches: P C P C Point Diameter Nom Screw Length Point Diameter Nom Screw Length Nominal Size Threads Per Inch Max Min Max Nomina
