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. 2015 by Navistar, Inc. JUNE 2015 Page 1 of 7 NAVISTAR, INC. Material, Parts, and Process Specifications (
2、MPAPS) NUMBER: MPAPS S-E-70.101-GS/PL Former Designation: ESP-E-70.101-GS TITLE: Spring Nuts (Flat “J” Shape “U” Shape) - English Series (Noun Code 5780) CURRENT REV No.: 1506 DATE: June 2015 WRITTEN/EDITED BY: Materials Engineering APPROVED BY: Materials Engineering SUPERSEDES: ESP-E-70.101-GS - Au
3、gust 2006 PRINTED COPIES OF THIS DOCUMENT MUST BE VERIFIED FOR CURRENT REVISION This specification may involve hazardous materials, equipment, and procedures. This specification does not purport to address all of the safety issues associated with its use. The user is responsible to consult appropria
4、te safety and health practices and to determine the applicability of regulatory limits prior to use. Change Notice: Changed to New MPAPS format; Combined GS, PP. 1.0 GENERAL: This specification covers performance and other requirements for spring nuts described in section 18.0, 19.0 and 20.0. Single
5、-thread engaging spring nuts are formed by stamping a thread-engaging Boss (impression) in a flat piece of metal. The Boss (impression) can take two shapes: 1. “Twin Prong“ in which shear-formed helical prong engage and lock on the screw thread root diameter. 2. “Cone“ in which a protruding truncate
6、d cone stamped into the metal provides a ramp that the screw climbs as it turns. 2.0 CONTENTS: Page General 1 Application 2 Dimension Tolerance 2 Boss (Impression) 2 Screw Length 2 Material 2 Finish 2 Restricted Chemical Substances 2 Recommended Hole Sizes For Flat Spring Nuts 2 Hardness 3 Assembly
7、Requirements 3 Retention Tests 3 Installation Torque and Back-Off Torque 3 Destructive Torque Test 3 Tensile Test 3 Vibration Test 3 Flat Spring Nuts 4 J-Shape Spring Nuts 4 U-Shape Spring Nuts 5 J-Shape and U-Shape Nut Assembly Data 5 Technical Information 7 NUMBER: MPAPS S-E-70.101-GS/PL TITLE: Sp
8、ring Nuts REVISION: 1506 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. 2015 by Navistar, Inc. JUNE 2015 Page 2 of 7 3.0 APPLICATIONS: Single-thread eng
9、aging spring nuts generally are used for lighter duty applications than multiple-thread nuts of the same size. These types of fasteners are often used to reduce assembly costs. Spring nuts do not require a large amount of torque; their holding power and resistance to vibration depend solely on sprin
10、g action. Corrosion of screw threads presents no problem with the engaging of one thread instead of several, spring nuts can be removed easily. When assembly conditions necessitate blind attachment from the front of a panel; “J“ shape spring nuts are preferable to “U“ shape when full bottom leg is n
11、ot required for full bearing surface in assembly. Tapping screw pitches are recommended when strength and speed of assembly are considerations or field servicing is involved. 4.0 DIMENSIONAL TOLERANCE: Tolerance on dimensions in the tables will be plus or minus .010 inch unless otherwise specified.
12、5.0 BOSS (IMPRESSION): The detail of Boss (impression) whether “Twin Prong“ or “Cone“ will be such as to assemble readily and function satisfactorily with the specified screw and nut performance requirements of this specification. 6.0 SCREW LENGTH: The proper machine screw length to be used with sin
13、gle-thread engaging nuts, is to allow 1-1/2 threads to protrude beyond the thread engaging element of the fastener. Sheet metal screws with tapered ends (Types AB, and B) should protrude two or three threads beyond the thread engaging element to assure engagement on the full screw root diameter. 7.0
14、 MATERIAL: Spring steel, 1050 thru 1065 per MPAPS A-0, Part I, suitably processed to meet the performance requirements of the specification. 8.0 FINISH: Two standard finishes “Phosphate Coated“ and “Rustproof.“ “Phosphate Coating“ will comply with Class B-1 per MPAPS G-1, which requires phosphate co
15、ating with subsequent oil coating to meet a 48 hour salt spray requirement. “Rustproof“ requires phosphate coating with two subsequent coats of hex-free zinc chromate paint (or paint standard with manufacturer) to meet 72 hour salt spray requirement. 9.0 RESTRICTED CHEMICAL SUBSTANCES: Effective Jan
16、uary 1, 2007, all product supplied to the requirements of this specification must comply with the requirements of the MPAPS B-50 specification. 10.0 RECOMMENDED HOLE SIZES FOR FLAT SPRING NUTS: Tests prove that flat spring nuts will withstand greater tensile loads if the screw holes provide a minimu
17、m amount of clearance. This does not apply to self-retaining spring nuts such as “U“ and “J“ types. Screw Hole Size Diameter 6 .156 8 .187 10 .218 14 .281 1/4 .281 3/8 .406 Reference Dimensions See section 17.0, 18.0 and 19.0 for part numbers. See section 20.0 for assembly data. NUMBER: MPAPS S-E-70
18、.101-GS/PL TITLE: Spring Nuts REVISION: 1506 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. 2015 by Navistar, Inc. JUNE 2015 Page 3 of 7 11.0 HARDNESS:
19、Hardness Specifications Material Thickness Rockwell Scale Dial Reading Conversion to Rockwell C Scale Up to 0.016 15N 81.5 - 85.5 42 - 50 0.017 - 0.024 30N 61.3 - 68.5 42 - 50 0.025 - 0.039 45N 45.5 - 55.0 42 - 50 0.040 and over C 42 - 50 42 - 50 12.0 ASSEMBLY REQUIREMENTS: The “J“ shape and “U” sha
20、pe spring nuts will pre assemble onto panels within the thickness ranges specified in the dimensional tables (section 19.0 and 20.0) and will remain pre assembled to the panels during final assembly operations. 13.0 RETENTION TESTS: Spring nuts will pre assemble onto test panels of thickness equal t
21、o the two extremes of the panel range specified, having minimum diameter holes located at the maximum edge distance. The retaining feature will snap into the hole, and a pull force of 3-lb. minimum, will be required to remove the nuts from the panel. 14.0 INSTALLATION TORQUE AND BACK-OFF TORQUE: A s
22、pring nut will be assembled on a test plate and test screws used will be Hexagon head, Type AB, 1-inch minimum length, phosphate and oil finish. When the test screw is tightened to the recommended installation torque, the back-off torques will not be less than the values specified on Table 1. The re
23、adings being taken when the screw first moves. Upon disassembly, the boss will return to a position that will accept re-entry of the screw. 15.0 DESTRUCTIVE TORQUE TEST: A spring nut will be assembled on a test plate, and torque applied to a test screw driven into the nut. Torque to cause failure of
24、 the nut will not be less than the value shown in Table 1. 16.0 TENSILE TEST: A spring nut will be assembled on a test plate, with a device capable of measuring tensile load on a test screw driven into the nut. The test screw will be engaged with the nut, but no pre load applied by torque. A tensile
25、 load will be applied to the test screw, and load to cause failure of the nut will not be less than the value shown in Table 1. 17.0 VIBRATION TEST: Conducted in accordance with SAE Standard J891, to meet figures listed in Table 1. Table 1 - Performance Requirements for Spring Nuts Screw Recom-mende
26、d Installation Torque, Max, lb-in Destruct-ive Torque, Min, lb.-in Back-Off Torque Min, oz-in Test Plate Separation in Tensile Yield Strength, lb Ultimate 1Tenslle Strength, lb. Vibration Test Load lb Cone Boss Twin Prong Boss Cone Boss Twin Prong Boss Type Size at 5 deg at 40 deg Twin Prong Boss 6
27、-32 * 6 8 33 26 16.5 0.004 89 155 156 25 8 -32 8 10 45 24.8 20.6 0.005 134 200 189 38 Machine 10 -24 14 17 78 48 40 0.006 221 315 274 50 1/4-20 35 45 195 256 216 0.008 350 570 550 85 6 -20 * 12 17 57 42.4 13.8 0.004 312 500 425 70 8 -18 20 25 96 120.6 54 0.005 420 620 534 95 10 -16 35 44 168 113.6 8
28、 0.006 525 1000 672 13 1/4-14 60 80 288 432 150 0.008 891 1130 1158 18 NUMBER: MPAPS S-E-70.101-GS/PL TITLE: Spring Nuts REVISION: 1506 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technical Standards. Suppliers are required t
29、o assume all patent liability. 2015 by Navistar, Inc. JUNE 2015 Page 4 of 7 These requirements will not apply to Cone Boss, Style 1, Flat Spring Nuts shown in section 18.0 due to the limitations on boss design imposed by the narrow widths and long lengths. See Section 18.0, 19.0 and 20.0 for part nu
30、mbers. See Section 21.0 for assembly data. 18.0 FLAT SPRING NUTS: 18.1 Part List: 18.1.1 Approved: Dimensions In inches: Screw STYLESINGLE BOSS Thickness D E C PART NUMBERS F Nut Length Nut Width Height STEEL Phos. Rust- Max Min Coated Proofed Max Min 10-16Types B & AB Tapping I .75 .500 .065 .035 1
31、87510 .033 .029 See Section 21.0 for assembly data. 19.0 J SHAPE SPRING NUTS: 19.1 Part List: 19.1.1 Approved: Dimensions In inches: Screw Panel Thickness Range STYLED E J G F K * L* M N H O PART NUMBERS LEG LENGTHNUT WIDTHEDGE TO CENTERTHROAT DEPTHStock Thickness NOTCH DEPTHWIDTHHEIGHTLEG LENGTHGAP
32、 WIDTHGAP WIDTHSTEEL Phos. Coated Rust Proof Max Min .015 .005 8-18 Types B & AB Tapping .045 to .062 II .53 .500 .250 .28 .030 .026 .015 .09 .025 .27 .08 .05 - 445389 10-24 Machine .045 to .062 I .78 .375 .187 .44 .024 .020 .110 .11 .025 .43 .07 .03 445353 - See Section 21.0 for assembly data. * Do
33、es not apply to Optional Cone Boss NUMBER: MPAPS S-E-70.101-GS/PL TITLE: Spring Nuts REVISION: 1506 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. 2015
34、by Navistar, Inc. JUNE 2015 Page 5 of 7 20.0 U - SHAPE SPRING NUTS: 20.1 Part List: 20.1.1 Approved: Dimensions In inches: Screw Panel Thickness Range STYLED E J G F K * L* M N P H O PART NUMBERS LEG LENGTHNUT WIDTHEDGE TO CENTERTHROAT DEPTHStock Thickness NOTCHDEPTHWIDTHHEIGHTLEG LENGTHTANG LENGTHT
35、ANG HEIGHTGAP WIDTHGAP WIDTHSTEEL Phos. Coated Max Min .015 .005 .015 .015 8-32 Machine .045 to .062 II .52 .500 .250 .26 .018 .016 .030 .09 .53 .090 .090 .07 .031 445427 8-18 Types B & AB Tapping .045 to .062 I .67 .406 .203 .35 .030 .026 .090 .17 .030 .69 .090 .090 .08 .031 445435* 10-24 Machine .
36、045 to .062 I .76 .375 .187 .41 .024 .020 .110 .12 .025 .76 .090 .090 .08 .031 445441 10-16 Types B & AB Tapping .045 to .062 II .56 .625 .312 .30 .033 .029 .020 .13 .025 .56 .090 .090 .08 .031 445444 .045 to .062 I .76 .500 .250 .42 .033 .029 .110 .12 .030 .76 .090 .090 .08 .031 445446 See Section
37、21.0 for assembly data. * Does not apply to Optional Cone Boss. 21.0 J-SHAPE AND U SHAPE NUT ASSEMBLY DATA: NUMBER: MPAPS S-E-70.101-GS/PL TITLE: Spring Nuts REVISION: 1506 This document is restricted and may not be sent outside Navistar, Inc. or reproduced without permission from Corporate Technica
38、l Standards. Suppliers are required to assume all patent liability. 2015 by Navistar, Inc. JUNE 2015 Page 6 of 7 Dimensions in inches: Screw Style D H HF FW FL J L M Float “J“ “U“ Shape Shape 6-20 Types B & AB Machine II 11/64 3/16 1/4 3/32 3/32 1/2 17/32 7/32 19/32 I 1/4 3/16 1/4 3/32 3/32 41/64 39
39、/64 7/32 9/16 Ill 27/64 3/16 1/4 3/32 3/32 53/64 25/32 7/32 9/16 6-18 “A” Tapping II 11/64 3/16 1/4 5/64 3/32 1/2 17/32 7/32 37/64 I 1/4 3/16 1/4 5/64 3/32 41/64 39/64 7/32 9/16 III 27/64 3/16 1/4 5/64 3/32 53/64 25/32 7/32 9/16 8-32 Machine II 3/16 7/32 9/32 5/64 3/32 37/64 39/64 1/4 37/64 I 9/32 7
40、/32 9/32 5/64 3/32 45/64 43/64 1/4 9/16 III 15/32 7/32 9/32 5/64 3/32 57/64 55/64 1/4 9/16 8-18 Types B & AB Tapping II 3/16 7/32 9/32 5/64 3/32 37/64 39/64 1/4 37/64 I 9/32 7/32 9/32 5/64 3/32 45/64 43/64 1/4 9/16 III 15/32 7/32 9/32 5/64 3/32 55/64 55/64 1/4 9/16 10-24 Machine II 13/64 1/4 5/16 5/
41、64 3/32 5/8 21/32 5/16 45/64 I 5/16 1/4 5/16 5/64 3/32 49/64 23/32 5/16 5/8 III 1/2 1/4 5/16 5/64 3/32 31/32 29/32 5/16 5/8 10-16 Types B & AB Tapping I1 13/64 1/4 5/16 5/64 3/32 5/8 21/32 5/16 45/64 I 5/16 1/4 5/16 5/64 3/32 25/32 23/32 5/16 5/8 III 1/2 1/4 5/16 5/64 3/32 31/32 29/32 5/16 5/8 1/4-1
42、4 Types B & AB Tapping I 3/8 5/16 3/8 3/32 3/32 57/64 55/64 7/16 11/16 III 5/8 5/16 3/8 3/32 3/32 1-9/64 1-7/64 7/16 11/16 3/8-12 “B” Tapping I 15/32 7/16 9/16 1/8 1/8 1-13/64 1-7/64 9/16 31/32 III 5/8 7/16 9/16 1/8 1/8 1-3/8 1-17/64 9/16 31/32 *This assembly data is for guidance only and is not to
43、be considered a part of the standard. The dimensions specified have been selected to accommodate both the twin prong and cone boss design. Tolerances on the nuts and toleranced of the manufacturing processes used to emboss and punch the various assembly features were not considered in the derivation
44、 of theses dimensions. NUMBER: MPAPS S-E-70.101-GS/PL TITLE: Spring Nuts REVISION: 1506 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. 2015 by Navistar,
45、 Inc. JUNE 2015 Page 7 of 7 Dimensions in inches: FW FL N S Screw Style D H HF K “J“ Shape “U“ Shape “J“ Shape “U” T Float Shape 6-32 Machine II 11/64 3/16 1/4 3/32 3/32 5/8 1/2 17/32 .045 .045 .025 I 1/4 3/16 1/4 3/32 3/32 9/16 37/64 39/64 .045 .045 .025 III 27/64 3/16 1/4 3/32 3/32 9/16 49/64 25/3
46、2 .045 .045 .025 6-20 Types B & AB Tapping II 11/64 3/16 1/4 5/64 3/32 39/64 1/2 17/32 .060 .060 .030 I 1/4 3/16 1/4 5/64 3/32 9/16 37/64 39/64 .060 .060 .030 III 27/64 3/16 1/4 5/64 3/32 9/16 49/64 25/32 .060 .060 .030 8-32 Machine II 3/16 7/32 9/32 5/64 3/32 39/64 37/64 39/64 .050 .050 .030 I 9/32
47、 7/32 9/32 5/64 3/32 9/16 41/64 43/64 .050 .050 .030 III 15/32 7/32 9/32 5/64 3/32 9/16 53/64 55/64 .050 .050 .030 8-18 Types B & AB Tapping II 3/16 7/32 9/32 5/64 3/32 39/64 37/64 39/64 .060 .060 .033 I 9/32 7/32 9/32 5/64 3/32 9/16 41/64 43/64 .065 .065 .033 III 15/32 7/32 9/32 5/64 3/32 9/16 53/6
48、4 55/64 .065 .065 .033 10-24 Machine II 13/64 1/4 5/16 5/64 3/32 47/64 5/8 21/32 .055 .055 .030 I 5/16 1/4 5/16 5/64 3/32 5/8 45/64 23/32 .055 .055 .030 III 1/2 1/4 5/16 5/64 3/32 5/8 29/32 29/32 .055 .055 .030 10-16 Types B & AB Tapping II 13/64 1/4 5/16 5/64 3/32 47/64 5/8 21/32 .065 .065 .036 I 5
49、/16 1/4 5/16 5/64 3/32 5/8 23/32 23/32 .065 .065 .036 III 1/2 1/4 5/16 5/64 3/32 5/8 29/32 29/32 .070 .060 .036 1/4-14 Types B & AB Tapping I 3/8 5/16 3/8 3/32 3/32 11/16 53/64 55/64 .085 .080 .042 III 5/8 5/16 3/8 3/32 3/32 11/16 1-5/64 1- 7/64 .085 .080 .042 3/8-12 “B” Tapping I 15/32 7/16 9/16 1/8 1/8 1-3/32 1-9/64 1- 7/64 .105 .100 .055 III 5/8 7/16 9/16 1/8 1/8 1-3/32 1-5/16 1-17/64 .105 .100 .055 *This assembly data is for guidance only and is not to be considered a part of
