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. 2008 by Navistar, Inc. MAY 2008 Page 1 of 6 NAVISTAR, INC. Engineering Standard Parts NUMBER: ESP-C-29.10
2、1-GS TITLE: Flanged 12- Point Screws General Specifications (Noun Code 7450)CURRENT ISSUE DATE: May 2008 WRITTEN/REVIEWED BY: Corporate Technical Standards APPROVED BY: Corporate Technical StandardsSUPERSEDES ISSUE OF: August 2006PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CURRENT REVISION
3、Change Notice: Zinc Trivalent plus Sealer (ZN8F) finished specification changed to Zinc Aluminum Clear (ZACLR) finish specification. Replaced International Truck and Engine Corporation with Navistar, Inc. per corporate directive.GENERAL: This standard conforms essentially with the SAE J58 Standard f
4、or Flanged 12-Point crews, with the notable exception of material. SPREFERRED PARTS POLICY: Preferred parts are so designated to reduce variety of parts and ssure maximum availability, interchangeability and cost savings in volume buying. aFinishes: Phosphate Coated (PHC) Material: International Typ
5、e 9 Threads: Unified Coarse Diameters: 1/4, 5/16, 3/8, 1/2, 5/8, 3/4, 1, 1-1/4, and 1-1/2 Lengths: All diameters - 1/4 inch increments thru inches. 1/4 and 5/16 diameters 1/2 inch increments - 4 thru 7 inches 1 inch increments - over 7 inches 3/8 thru 1-1/2 diameters 1/2 inch increments - 4 thru 9 i
6、nches 1 inch increments - over 9 inches SERVICE PARTS SUBSTITUTION POLICY: In the event that engineering does not indicate a “Do not substitute“ in engineering specifications, the following substitutions may be implemented in service. This policy is the result of a proposal circulated April 20, 1981
7、, and subsequently approved by engineering departments worldwide. Flanged 12-Point Screws To Be Replaced Service ReplacementPlain (PLN) Finish Phosphate Coated (PHC) Finish TOP OF HEAD: The top of head may be full form or indented at the option of the manufacturer. If full form, the top of head will
8、 be chamfered or rounded with the diameter of chamfer circle or start of rounding being equal to the specified maximum width across flats within a tolerance of -15%. If the top f head is indented, the periphery may be rounded. oCORNER FILL: The rounding due to lack of fill at all 12 corners of the h
9、ead will be reasonably uniform and the width across corners of the head be such that when a sharp ring, having an inside diameter equal to the “T“ dimension and a thickness within the limits for “A“ specified in dimensional table, is placed on the top of the head, normal to the screw axis, the head
10、may enter but will not protrude hrough the gage. tWRENCHING HEIGHT: The wrenching height will be measured, parallel to the axis of screw, from the intersection of the top contour of flange with any corner of head to the top of the head. Copyright Navistar International Corporation Provided by IHS un
11、der license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-C-29.101-GS TITLE: Flanged 12 Point Screws General Specifications CURRENT ISSUE DATE: May 2008 This document is restricted and may not be sent outside Navistar, Inc. or reproduced wi
12、thout permission from Corporate Technical Standards. Suppliers are required to assume all patent liability. 2008 by Navistar, Inc. MAY 2008 Page 2 of 6 BEARING SURFACE: The outer periphery may be rounded or chamfered to the extent permitted by “X,“ as measured on the bearing face. The plane of the b
13、earing face will be perpendicular to the axis of screw within the runout limit specified in dimensional table. Measurement of runout will be made as close to the periphery of bearing face as possible while the screw is held in a collet or other gripping device at a distance equal to one screw diamet
14、er from the underside of the head. LENGTH: The length of the screw (L) will be measured on a line parallel to the axis, from the plane of the bearing surface under the head, to the plane of the flat of the point. The tolerances for length are as follows: 0 7/16 7/8 Nominal Screw Size thru thru thru
15、3/8 3/4 1-1/2 Nominal Screw Length, in Tolerance on LengthUp to 1, incl -.03 -.03 -.05 Over 1 to 2-1/2, incl -.04 -.06 -.10 Over 2-1/2 to 6, incl -.06 -.08 -.14 Over 6 -.12 -.12 -.20 BODY DIAMETER: On screws threaded full length, the diameter of the screw under the head will not be less than the spe
16、cified minimum pitch diameter of the thread. THREADS: Unified coarse or fine series (UNC or UNF), Class 3A limits will apply. LENGTH OF THREAD: The length of thread on screws will be controlled by grip length LG max and the body length LB min as set forth in the following: Grip Gaging Length - LG ma
17、x is the distance, measured parallel to the axis of screw, from the underside of head to the face of a noncounterbored or nonchamfered standard GO thread ring gage assembled by hand as far as the thread will permit. It represents the minimum design grip length and will be used as the criterion for i
18、nspection and for determining thread availability when selecting screw lengths even though usable threads may extend beyond this point. Values for LG max applicable to common nominal screw lengths are shown in Table 1. For screws having nominal lengths which fall between those tabulated in Table 1,
19、the LG max value hown for the next shorter tabulated nominal length and respective screw size will apply. sFor screws having nominal lengths longer than those specified in Table 1 for the respective screw size, the LG max value will be determined by subtracting the LT value from the nominal screw le
20、ngth. For screws having shorter nominal lengths than those specified in Table 1 for the respective screw size, the complete (full form) thread, as measured with a thread ring gage, will extend to within two threads (pitches) of the bearing face for sizes up to and including 5/8 in, and as close to t
21、he head as practicable for larger sizes. Body Length - LB min is the distance, measured parallel to the axis of screw, from the underside of the head to the last scratch of thread or the top of extrusion angle. The minimum body length for any screw length will be equal to the maximum grip length min
22、us the transition thread length (LB min = LG max - max). It will be used as a criterion for inspection. YCopyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-C-29.101-GS TI
23、TLE: Flanged 12 Point Screws General Specifications CURRENT ISSUE DATE: May 2008 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. 2008 by Navistar, Inc. M
24、AY 2008 Page 3 of 6 Basic Thread Length - LT is a reference dimension, intended for calculation purposes only, which epresents the distance from the extreme end of the screw to the last complete (full form) thread. rTransition Thread Length - Y max is a reference dimension, interviewed for calculati
25、on purposes only, which represents the length of incomplete threads and the tolerance on grip length. Point - The point will be flat and chamfered from a diameter approximately .016 inch below the minor iameter of thread to produce a length of point equivalent to 1/2 to 1-1/2 threads (pitches). dInc
26、omplete Thread Diameter - The major diameter of incomplete thread will not exceed the actual major diameter of the full form thread. Thread Runout - The total runout between thread, body, and head of screws will be such that screw may be assembled for a minimum of two full turns into the threaded ho
27、le of a concentricity sleeve gage s shown below. aTABLE 1 - MAXIMUM GAGING LENGTHS (LG ) Dimensions in inches: Nominal Nominal Size Length 1/4 5/16 3/8 7/16 1/2 9/16 5/8 3/4 7/8 1 1-1/8 1-1/4 1-3/8 1-1/2 1-1/2 .500 - - - - - - 1-3/4 .500 .625 .500 - - - - -2 1.000 .625 .500 .625 - - - 2-1/4 1.000 1.
28、125 1.000 .625 .750 .750 - 2-1/2 1.500 1.125 1.000 1.125 .750 .750 .750 - - -2-3/4 1.500 1.625 1.500 1.125 .750 .750 .750 - - - 3 2.000 1.625 1.500 1.625 1.500 1.500 .750 1.000 - - - 3-1/4 2.000 2.125 2.000 1.625 1.500 1.500 1.500 1.000 1.000 - - 3-1/2 2.500 2.125 2.000 2.125 1.500 1.500 1.500 1.000
29、 1.000 1.000 - - - - 3-3/4 2.500 2.625 2.500 2.125 2.250 2.250 1.500 1.000 1.000 1.000 1.000 - - - 4 3.000 2.625 2.500 2.625 2.250 2.250 2.250 2.000 1.000 1.000 1.000 1.000 - - 4-1/4 3.000 3.125 3.000 2.625 2.250 2.250 2.250 2.000 1.000 1.000 1.000 1.000 1.000 - 4-1/2 3.500 3.125 3.000 3.125 3.000 3
30、.000 2.250 2.000 2.000 2.000 1.000 1.000 1.000 1.000 4-3/4 3.500 3.625 3.500 3.125 3.000 3.000 3.000 2.000 2.000 2.000 2.000 1.000 1.000 1.000 5 4.000 3.625 3.500 3.625 3.000 3.000 3.000 3.000 2.000 2.000 2.000 2.000 1.000 1.000 5-1/4 - 4.125 4.000 3.625 3.750 3.750 3.000 3.000 3.000 2.000 2.000 2.0
31、00 2.000 1.000 5-1/2 - 4.125 4.000 4.125 3.750 3.750 3.750 3.000 3.000 3.000 2.000 2.000 2.000 2.000 5-3/4 - 4.625 4.500 4.125 3.750 3.750 3.750 3.000 3.000 3.000 3.000 2.000 2.000 2.000 6 - 4.625 4.500 4.625 4.500 4.500 3.750 4.000 3.000 3.000 3.000 3.000 2.000 2.000 6-1/4 - 5.125 5.000 4.625 4.500
32、 4.500 4.500 4.000 4.000 3.000 3.000 3.000 3.000 2.000 6-1/2 - 5.125 5.000 5.125 4.500 4.500 4.500 4.000 4.000 4.000 3.000 3.000 3.000 3.000 6-3/4 - - 5.500 5.125 5.250 5.250 4.500 4.000 4.000 4.000 4.000 3.000 3.000 3.000 7 - - 5.500 5.625 5.250 5.250 5.250 5.000 4.000 4.000 4.000 4.000 3.000 3.000
33、 7-1/4 - - 6.000 5.625 5.250 5.250 5.250 5.000 5.000 4.000 4.000 4.000 4.000 3.000 7-1/2 - - - 6.125 6.000 6.000 5.250 5.000 5.000 5.000 4.000 4.000 4.000 4.000 7-3/4 - - - 6.125 6.000 6.000 6.000 5.000 5.000 5.000 5.000 4.000 4.000 4.000 8 - - - 6.625 6.000 6.750 6.000 6.000 5.000 5.000 5.000 5.000
34、 4.000 4.000 8-1/2 - - - 7.125 7.000 6.750 6.750 6.000 6.000 6.000 5.000 5.000 5.000 4.000 9 - - - 7.625 7.000 7.750 6.750 7.000 6.000 6.000 6.000 5.000 5.000 5.000 9-1/2 - - - - 8.000 7.750 7.750 7.000 7.000 7.000 6.000 6.000 5.000 5.000 10 - - - - 8.000 9.25 7.750 8.000 7.000 7.000 7.000 6.000 6.0
35、00 5.000 11 - - - - - 10.25 9.25 9.000 8.000 8.000 7.000 7.000 6.000 6.000 12 - - - - - 10.25 10.000 9.000 9.000 8.000 7.000 7.000 6.000 13 - - - - - - 11.000 10.000 10.000 9.000 8.000 7.000 7.000 14 - - - - - - 12.000 11.000 11.000 10.000 9.000 8.000 7.000 15 - - - - - - 13.000 12.000 12.000 11.000
36、 10.000 9.000 8.000 16 - - - - - - 13.000 13.000 12.000 11.000 10.000 9.000 17 - - - - - - 14.000 14.000 13.000 12.000 11.000 10.000 18 - - - - - - 15.000 15.000 14.000 13.000 12.000 11.000 19 - - - - - - - 16.000 15.000 14.000 13.000 12.000 20 - - - - - - - 17.000 16.000 15.000 14.000 13.000 Copyri
37、ght Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-C-29.101-GS TITLE: Flanged 12 Point Screws General Specifications CURRENT ISSUE DATE: May 2008 This document is restricted an
38、d may not be sent outside Navistar, Inc. or reproduced without permission from Corporate THREAD RUNOUT AND BOW OF SHANK: A gage capable of checking the head and thread eccentricity along with the bow of shank on screws is illustrated below. The gage construction incorporates three primary components
39、: ring gage A, shank sleeve B2and head sleeve B1. Shank sleeve length can be varied to accommodate different lengths of product and also diameters D2and D1can be varied depending on the screw diameter and head size, respectively. Ring gage A and head sleeve B1and centered on the sleeve B2by means of
40、 the positioning plug shown below the gage proper and are secured in position by means of attachment screws C. The ring gage A is also set to Class 3B maximum pitch diameter. Diameter D1, of the head sleeve, equals the maximum flange diameter of the screw plus .031 inch allowance. Diameter D2, of th
41、e shank sleeve, equals the maximum screw diameter plus the runout allowance given on the following page as a function of product length. The shank sleeve length L2should be such that entering face of gage A extends beyond the last thread of the product to be inspected. Failure of the screw to enter
42、the threads of gage or interference between the sides of hole D1or D2and the screw while engaging threads of the gage indicates excessive runout. MATERIAL: International Class 9, per CEMS A-31, Part I. FINISH: As designated by part number, screws will be furnished plain, plated or coated in accordan
43、ce with the International Engineering Material Specification and class listed below: Plain (PLN). Zinc Aluminum Clear (ZACLR) TMS-4518, Type I. Phosphate Coated (PHC) CEMS G-1, Class B-2. High strength steel fasteners, e.g., Type 9 and Class 12.9 are more susceptible to hydrogen embrittlement than l
44、ower strength fasteners. Thus electrochemical plating is not preferred. However, if this process cannot be avoided and is specified, the fasteners must be treated at an appropriate temperature for a sufficient period of time to remove hydrogen from the material as stated in A-31, Part I, Surface Coa
45、tings and A-31 Appendix. 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. Technical Standards. Suppliers are required to assume all patent liability. 2008 by Nav
46、istar, Inc. MAY 2008 Page 4 of 6 Copyright Navistar International Corporation Provided by IHS under license with INTERNNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-NUMBER: ESP-C-29.101-GS TITLE: Flanged 12 Point Screws General Specifications CURRENT ISSUE DATE:
47、May 2008 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate SURFACE DISCONTINUITIES: Surface discontinuities will be determined by methods shown in CEMS A-31, Part I. Flanged 12-Point Screws Dimensions in inches E C F D H J K Flange
48、 Diameter Width Across Flats Width Across Corner Head Height Wrenching Height Flange ThicknessNominal Size Or Basic Major Dia of Thread Body Dia Min (Max Equal to Nom Size) Max Min Max Min Min Max Min Min 1/4 .2500 .2435 .375 .365 .252 .244 .278 .260 .15 .058 5/16 .3125 .3053 .469 .457 .315 .306 .34
49、8 .312 .18 .074 3/8 .3750 .3678 .562 .550 .377 .368 .420 .375 .21 .095 * 7/16 .4375 .4294 .656 .642 .438 .429 .489 .438 .26 .109 1/2 .5000 .4919 .750 .735 .502 .493 .562 .500 .29 .129 * 9/16 .5625 .5538 .844 .828 .564 .555 .633 .563 .33 .145 5/8 .6250 .6163 .938 .921 .627 .618 .705 .625 .36 .166 3/4 .7500 .7406 1.125 1.107 .752 .743 .847 .750 .44 .200 * 7/8 .8750 .8647 1.312 1.293 .877
