1、Designation:E197406 Designation: E1974 11Standard Specification forShelter, Electrical Equipment S-250/G1This standard is issued under the fixed designation E1974; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last re
2、vision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This specification covers one type of lightw
3、eight field and mobile rigid wall shelter designed for transport by cargo truck,fixed or rotary winged aircraft, by rail, and ship, designated as Shelter, Electrical Equipment S-250/G.1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are fo
4、r informationonly.1.3 The following safety hazards caveat refers only to the test methods portion of this specification. This standard does notpurport to address the safety concerns, if any, associated with its use. It is the responsibility of the user of the standard to establishappropriate safety
5、and health practices and determine the applicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C273 Test Method for Shear Properties of Sandwich Core MaterialsD1621 Test Method for Compressive Properties of Rigid Cellular PlasticsD1622 Test Method for Apparent
6、 Density of Rigid Cellular PlasticsD2842 Test Method for Water Absorption of Rigid Cellular PlasticsE1370 Guide for Air Sampling Strategies for Worker and Workplace ProtectionE1749 Terminology Relating to Rigid Wall Relocatable SheltersE1773 Practice for Sealing Rigid Wall Tactical Shelters with Pol
7、ysulfide Based SealantsE1800 Specification for Adhesive for Bonding Foam Cored Sandwich Panels (160F Elevated Humidity Service), Type I PanelsE1801 Practice for Adhesive Bonding of Aluminum Facings in Foam and Beam Type SheltersE1851 Test Method for Electromagnetic Shielding Effectiveness of Durable
8、 Rigid Wall Relocatable StructuresE1925 Specification for Engineering and Design Criteria for Rigid Wall Relocatable Structures2.2 Commercial Standards:3SAE AMS-W-6858 Welding, Resistance: Spot and Seam2.3 Federal Air Regulation (FAR):4FAR 25.853 Compartment Interior2.4 Military Standards:5MIL-F-140
9、72 Finishes for Ground Based Electronic EquipmentMIL-DTL-55507 Shelter, Electrical Equipment (With or Without Equipment), Packaging ofMIL-STD-252 Wired Equipment, Classification of Visual and Mechanical DefectsMIL-STD-810 Environmental Engineering Considerations and Laboratory TestsMIL-STD-2219 Fusi
10、on Welding for Aerospace ApplicationsMIL-STD-13231 Marking of Electronic Items2.5 Drawings:6DL-SM-B-563500 Shelter, Electrical Equipment, S-250/G1This specification is under the jurisdiction of ASTM Committee E06 on Performance of Buildings and is the direct responsibility of Subcommittee E06.53 on
11、Materialsand Processes for Durable Rigid Wall Rigidwall Relocatable Structures.Current edition approved Oct.Sept. 1, 2006.2011. Published October 2006.2011. Originally approved in 1998. Last previous edition approved in 20012006 asE197401a.E1974 06. DOI: 10.1520/E1974-06.10.1520/E1974-11.2For refere
12、nced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3Available from AMS Publications, Society of Automotive Engineers (SAE
13、), 400 Commonwealth Dr., Warrendale, PA 15096-0001, http:/www.sae.org.4Available from Flight Standards Service, Federal Aviation Administration (FAA), 800 Independence Ave., SW, Washington, DC 20591, http:/www.faa.gov.5Available from Standardization Documents Order Desk, DODSSP, Bldg. 4, Section D,
14、700 Robbins Ave., Philadelphia, PA 19111-5098, http:/www.dodssp.daps.mil.6Available from US Army Natick Soldier Center, ATTN: AMSRD-NSC-CP-CS, Kansas Street, Natick, MA 01760-5018.1This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of wha
15、t changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the
16、 official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.DL-SM-B-649950 Modification Kit, EMI, MK-1092/GDL-SM-B-650123 Shelter, Electrical Equipment, S-250/G (Shielded)SM-D-208679 Outer Door AssemblySM-D-208682 Inner Door As
17、semblySM-C-435904 KeeperSM-C-435937 NameplateSM-B-563559 AdhesiveSM-B-563655 Foam, Rigid, PlasticSM-D-563754 Diagram, Flatness and SquarenessSM-C-564839 Gasket, SiliconeSC-C-595537 Padlock and KeySC-B-595538 Bonding ProcedureSC-B-595539 Cleaning ProcedureSC-B-595564 Core Material Urethane, LightSC-B
18、-595565 Core Material Urethane, HeavySM-D-649951 Modification Kit EMI MK-1092/GSM-D-649952 Sling AssemblySM-D-649953 Shelter, Electrical Equipment S-250/GSM-C-650082 Skid AssemblySM-D-650085 Test Weight InstallationSM-C-650125 NameplateSC-D-781228 Door Fixture Construction Tightness TestSC-D-781235
19、Drain, Fixture, Construction Tightness TestSC-D-781236 Test Fixture Installation Construction Tightness TestSC-B-964240 Nameplate, S-250 Shelter (With Rivnuts)3. Terminology3.1 Definitions:3.1.1 delaminationsfor purpose of this specification, a delamination is defined as the condition that exists wi
20、thin a sheltersection or panel when two surfaces that once were bonded together are no longer bonded together. Delaminations may occurbetween any two bonded surfaces; examples include: separations between thermal barriers and members, between thermal barriersand skins, between members and core, or b
21、etween skins and core. They may be the result of a poor quality bond or they couldoccur due to misuse or severe handling of the panels or the shelter after bonding. Test requirements of this specification shall notbe construed as misuse or severe handling as these terms apply to the definition of de
22、laminations.3.1.2 examinationexamination consists of simple, generally nondestructive determinations of compliance, without the use ofspecial testing equipment.3.1.3 inspectioninspection is the examination or testing, or both, of supplies to determine compliance with the applicablerequirements. Samp
23、ling an element of inspection.3.1.4 testingtesting consists of determinations of compliance using technical means.3.1.5 voidsfor the purpose of this specification, a void is defined as any unauthorized separation or space within a shelter panelor section, that is, any separation or space that is in
24、conflict with the drawings or other contractual requirements. Voids range fromgaps as wide as the space created by a missing piece of core material to as thin as a break in the continuity of material. Voids maybe located solely within one type of material, such as a core material separation; they ma
25、y exist between adjacent materials, suchas unbonded core material; or they may be located between other parts within a panel, such as where a piece of material is missing,damaged, or undersized. Voids may have been created at the time of construction such as where a part was omitted; or may becreate
26、d at a later time, such as a core separation or delaminated skin.NOTE 1All other terminology related to this specification is defined in Terminology E1749.4. Materials Requirements4.1 GeneralThe materials and components shall be as specified herein and on the applicable drawings. Materials andcompon
27、ents not definitely specified shall be of the quality normally used by the manufacturer provided the completed itemcomplies with all the provisions of this specification.4.2 AdhesiveThe adhesive used to laminate in accordance 5.2 shall meet the requirements of Specification E1800 and thephysical pro
28、perties required by Drawing SM-B-563559 when tested in accordance with 10.1.4.3 SealerThe sealer, when tested in accordance with 10.1, used to meet the requirements of 5.3, shall have the followingproperties:4.3.1 Sealer Shear, AmbientThe sealer and its bond to the aluminum shall have a minimum aver
29、age shear strength of 200 psi(1.4 MPa) when tested at 80 6 10F (27 6 6C).E1974 1124.3.2 Sealer Shear, Temperature ExtremeThe sealer and its bond to the aluminum shall have a minimum average shearstrength of:4.3.2.1 200 psi (1.4 MPa) when tested at 65 6 5F (54 63C), and4.3.2.2 75 psi (520 KPa) when t
30、ested at 200+05F(93+03C)4.3.3 Sealer Shear, Humidity ExposureThe sealer and its bond to the aluminum shall withstand exposure to 95 % relativehumidity 6 5 % at 160 6 5F (71 6 3C) for fourteen days.After exposure the sealer shall have a minimum average shear strengthof 75 psi (520 kPa) when tested at
31、 160 6 5F (71 6 3C).4.3.4 Sealer Shear, Salt Spray ExposureThe sealer and its bond to the aluminum shall withstand exposure to the salt spraytest, Method 509.4 of MIL-STD-810F using a 20 % NaCl solution at 95 6 5F (35 63C) for fourteen days. After exposure thesealer shall have a minimum average shea
32、r strength of 200 psi (1.4 MPa) when tested at 80 6 10F (27 6 6C).4.4 Core MaterialThe core material shall be a slab type foamed plastic. All three densities shall be used in the shelter.Disbursement within the shelter shall be in accordance with Specification E1370 and the drawings listed on DL-SM-
33、B-563500Density, compressive strength, flammability, water absorption, and shear strength properties shall be in accordance with DrawingsSC-B-595564, SC-B-595565, and SM-B-563655, as applicable when tested in accordance with 10.2.5. Construction Requirements5.1 GeneralAll parts, sub-assemblies, and
34、the final assembly of Shelter, Electrical Equipment, S-250/G shall be constructedas specified herein and in accordance with the drawings listed on DL-SM-B-563500 or DL-SM-B-650123 when electromagneticinterference suppression is required (see 15.2). Shelters shall not be fork lifted at anytime during
35、 or after construction.5.2 LaminationDuring the laminating (bonding) process the mating of all panel constituents shall be bonded withoutdelaminations, that is, discontinuation in, or separation between the constituents. Bonding shall be in accordance with PracticeE1801 and SC-B-595538 Both sides of
36、 all panels prior to assembly into shelter form and all shelters shall be acousticallyinterrogated for delaminations using a tap hammer fabricated in accordance with Fig. 1. The shelter may be considered acceptableif it contains less than twelve distinctly individual delaminations or unbond type voi
37、ds, provided none is greater than 2 in. (50 mm)across measured in any direction, and provided the shelter meets all other requirements.5.3 SealAll inner and outer skins, joints, edges, and hardware shall be sealed in a manner that will prevent collection andretention of water and provide a barrier a
38、gainst the entrance of water into any panel or the interior of the shelter. Unless otherwisespecified on the shelter drawings, all exterior rivets, rivnuts, screws, and bolts shall be dipped in sealer prior to installation andthe heads of rivets shall be covered with sealant after installation. (See
39、 Practice E1773).5.4 CleaningAll metal parts shall be cleaned at that stage of assembly indicated on the applicable drawing listed onDL-SM-B-563500 or DL-SM-B-650123, by a process in accordance with Practice E1773 and Drawing SC-B-595539 or asspecified in the applicable portion of MIL-F-14072 All fo
40、am and wood parts shall be cleaned in accordance with the applicableportions of Practice E1801 and Drawing SC-B-595538. and Drawing SC-B-595538.5.5 WeldingArc and spot welding shall be applied as specified by the drawings. No grinding of welds shall be required exceptas specified by the drawings. Th
41、e purchaser reserves the right to perform any of the inspections where such inspections are deemednecessary to ensure supplies and services conform to prescribed requirements.5.5.1 Arc WeldingInert gas shielded arc welding shall be in accordance with MIL-STD-2219.5.5.2 Spot WeldingSpot welding shall
42、 be in accordance with SAE AMS-W-6858 Class B. Samples of the production itemsproduced in accordance with the drawings shall be inspected by the supplier for appearance, external defects, sheet separation,surface identification, and weld location.5.5.2.1 Test specimens shall be used to represent the
43、 manufacturing practice. Three single-spot shear specimens shall be usedfor checking purposes. Three single shear specimens shall be tested for ultimate strength and variation in shear strength.NOTE 1MaterialAluminum 6061T6 or equivalent.NOTE 2Tolerance6132 (1 mm).FIG. 1 Tap HammerE1974 1135.5.2.2 F
44、ailure of a test specimen or samples of a welded item shall be cause for rejection of the production quantity thespecimen or sample represents.5.6 RivetingNo more than one rivet/rivnut in ten and no more than two adjacent rivets/rivnuts shall exhibit any of the defectsspecified below, when inspected
45、 as specified in 10.6.5.6.1 LoosenessThere shall be no evidence of looseness parallel to the plane of the mating surface due to oversized holes orlooseness perpendicular to the plane of the mating surfaces due to rivets/rivnuts not being tightly seated.5.6.2 HeadsRivet and rivnut heads shall not be
46、cut, marred, chipped, eccentric, distorted, or otherwise mutilated. Countersunkrivets and rivnuts shall not project above or below the mating surface more than 15 % of the netting material thickness.5.6.3 Mating Surface and MaterialsThe mating surface shall not be marred or indented due to rivet or
47、rivnut installation, norshall there be any distortion or warpage of the mating materials. There shall be no foreign material between riveted surfaces.5.7 HardwareAll locks, latches, hinges, hinge pins, fasteners, bolts lifting and towing eyes, steps and other shelter hardwareshall be made corrosion
48、resistant in accordance with the applicable drawings listed on DL-SM-B-563500 or DL-SM-B-650123.The hardware shall be subjected to the test of 10.7 and shall show no evidence of corrosion or damage which in any way impairsthe specified performance of the individual part.5.7.1 Padlocks and KeysAll pa
49、dlocks and keys shall be in accordance with SC-C-595537 and shall be interchangeable to theextent determined by 10.10.5.8 Finish ProtectiveProtective finishes shall be in accordance with the applicable drawings listed on DL-SM-B-563500 orDL-SM-B-650123 and shall be free of the defects cited in the classification of visual finish defects of MIL-F-14072 when inspectedas specified in 10.8 and 10.12.5.9 MarkingMember centerline, punch marks, nameplates, instruction and data plates, and other markings shall be inaccordance wi
