6426-201-19266

METRIC MIL-DTL-38999/28H 12 May 2015 SUPERSEDING MIL-DTL-38999/28G 30 May 2008 DETAIL SPECIFICATION SHEET CONNECTORS, ELECTRICAL, CIRCULAR, NUT, HEXAGON, CONNECTOR MOUNTING, SERIES III AND IV, METRIC This specification is approved for use by all Departments and Agencies of the Department of Defense. The requirements for acquiring the product described herein shall consist of this specification sheet and MIL-DTL-38999. SEE NOTE 5 FIGURE 1. Nut, hexagon. AMSC N/A FSC 5935 MIL-DTL-38999/28H Dash number Shell size Series III Series IV, and MIL-DTLMIL-DTL38999/44 38999/43 only of series IV A thread size P hex X’ + .29 - .00 X + .45 - .00 1 9 -------- M17X1 – 6H (see note 3) 24.00 21.82 4.54 3.17 2 11 -------- M20X1– 6H (see note 4) 27.00 24.99 4.54 3.17 3 13 11 M25X1 – 6H 32.00 29.77 4.54 3.17 4 15 13 M28X1– 6H 36.00 32.91 4.54 3.17 5 -------- 15 M31X1 – 6H 41.00 39.26 4.54 3.17 6 17 -------- M32X1 – 6H 37.00 36.12 4.54 3.17 7 ------- 17 M34X1 – 6H 41.00 39.25 4.54 3.17 8 19 ------- M35X1 – 6H 41.00 39.25 4.54 3.17 9 21 19 M38X1 – 6H 46.00 42.47 4.54 3.17 23 21 M41X1 – 6H 50.00 45.61 4.54 3.17 25 23 M44X1 – 6H 51.23 49.25 4.54 3.17 ------- 25 M47X1 – 6H 55.00 53.54 4.54 3.17 10 11 12 NOTES: 1. Dimensions are in millimeters. Inch equivalents are given for information only. 2. Remove all burrs and sharp edges. 3. Modified minor diameter: 16.04 – 16.15 mm (.631 - .636 inches). 4. Modified minor diameter: 19.07 – 19.15 mm (.751 - .754 inches). 5. Standard safety wire holes are drilled. The safety wire openings depicted in the alternate design are crimped. The alternate hex nut with a crimped edge is specified by adding a “-C” to the Part or Identifying Number (PIN). FIGURE 1. Nut, hexagon – Continued. 2 MIL-DTL-38999/28H mm Inches mm Inches mm Inches mm Inches 0.29 .011 24.00 .945 36.12 1.422 46.00 1.811 0.45 .018 24.99 .984 37.00 1.457 49.25 1.939 0.75 .0295 27.00 1.063 39.25 1.545 50.00 1.969 1.5 .059 29.77 1.172 39.26 1.546 51.23 2.017 3.17 .125 32.00 1.260 41.00 1.614 53.54 2.108 4.54 .178 32.91 1.296 42.47 1.672 55.00 2.165 21.82 .859 36.00 1.417 45.61 1.796 REQUIREMENTS: Dimensions and configurations: See figure 1. Material: See table I. Finish: See table I and MIL-DTL-38999. Applicable jam-nut connectors: See MIL-DTL-38999, series III and IV. TABLE I. Material and finish. 1/ Hex nut finish code Material Finish C Aluminum alloy Anodic (nonconductive) F Aluminum alloy Electroless nickel coating (conductive) W Aluminum alloy X Aluminum alloy T Aluminum alloy Z Aluminum alloy Zinc nickel, non-reflective (conductive) K Corrosion resistant steel 2/ Passivated (conductive) N Corrosion resistant steel 2/ J Resin with or without filler M Resin with or without filler Electroless nickel coating, (conductive) V Resin with or without filler Unplated (no finish) Olive-drab cadmium plate over a suitable underplate (conductive) Same as W, but higher corrosion requirement Nickel fluorocarbon polymer, non-reflective (conductive) Electrodeposited nickel plating (conductive) Olive-drab cadmium plate over a suitable underplate (conductive) 1/ See MIL-DTL-38999. 2/ Shall be cleaned, descaled and passivated in accordance with SAE-AMS2700. 3 Applicable connector class code C F, G, R W X T Z K, H, Y N, S, L J M J, M MIL-DTL-38999/28H Qualification. Qualification shall be in accordance with MIL-DTL-38999, except only the following tests shall be required: Examination of product. Safety wire hole pull-out (see requirement below). Salt spray (corrosion). Safety wire pull-out: Safety wire shall not pull out of hex nuts with crimped edges when safety wire NI-CU alloy (MONEL™) (UNS NO4400) or NI-CR alloy (INCONEL™) (UNS NO6600) 0.51 mm (.020 inch) diameter in accordance with NASM20995 is threaded through a hole and a pull of 133.5 Newton (30 lb) minimum is applied. Nine pulls total shall be applied. Pulls shall be applied in three directions. Pulling forces shall be applied parallel with the axis of the nut and also perpendicular to the axis of the nut. Three pulls shall be applied parallel to the axis in one direction and three pulls shall be applied parallel to the axis in the opposite direction. An additional three pulls shall be applied perpendicular to axis of nut. Group A inspection shall consist of examination of product and safety wire pull-out. Sampling for group A inspection shall be as specified in table II. TABLE II. Group A sampling plan. Lot size Sampling size 1 to 13 100 percent 14 to 150 13 units 151 to 280 20 units 281 to 500 29 units 501 to 1,200 34 units 1,201 to 3,200 42 units 3,201 and up 54 units Part or Identifying Number (PIN) example: D38999 /28 -11 F -C MIL number prefix Specification sheet number Dash number (see figure 1) Finish code (see table I) Safety wire holes (Standard safety wire holes are drilled. No PIN designator code is used when hex nuts with drilled safety wire holes are specified. When a hex nut with crimped edges is required, a “-C” designator shall be added to the end of the PIN to indicate a crimped design.) 4 MIL-DTL-38999/28H Changes from previous issue. The margins of this specification are marked with vertical lines to indicate where changes from the previous issue were made. This was done as a convenience only and the Government assumes no liability whatsoever for any inaccuracies in these notations. Bidders and contractors are cautioned to evaluate the requirements of this document based on the entire content irrespective of the marginal notations and relationship to the last previous issue. Referenced documents. In addition to MIL-DTL-38999, this document references the following: MIL-DTL-38999/43 MIL-DTL-38999/44 NASM20995 SAE-AMS2700 CONCLUDING MATERIAL Custodians: Army – CR Navy - AS Air Force - 85 DLA – CC Preparing activity: DLA - CC (Project 5935-2015-118) Review activities: Army - AR, MI Navy - EC, MC, SH Air Force - 19, 99 NOTE: The activities listed above were interested in this document as of the date of this document. Since organizations and responsibilities can change, you should verify the currency of the information above using the ASSIST Online database at https://assist.dla.mil. 5