1、MIL-U-47071A TH 777770b 05757b8 4 W INCH-POUND MIL-W-47091A (MI) 30 June 1992 SUPERSEDING MIL-W-47091 (MI) 24 May 1974 I MILITARY SPECIFICATION WELDING, ARC AND GAS; FOR FABRICATING GROUND EQUIPMENT FOR ROCKETS AND GUIDED MISSILES This specification is approved for use by the U.S. Army Missile Comma
2、nd, Department of the Army, and is available for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers electric arc and gas welding of metallic members in ground handling equipment for rockets and guided missiles. Beneficial comments (recomme
3、ndations, additions, de1etions)and any pertinent data which may be of use in improving this document should be addressed to: Commander, U.S. Army Missile Command, ATTN: AMSMI-RD-SE-TD-ST, Redstone Arsenal, AL 35898-5270 by using the Standardization Document Improvement Proposal (DD Form 1426) appear
4、ing at the end of this document or by letter. AMSC N/A FSC THJM DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-W-Y709LA TH 999990b 0575769 b MIL-W-47 0 91A (MI) 1.
5、2 Classification. Welding covered by this specification shall be classified according to the base metal and shall be of the following types as specified (see 3.2). 2. a. Type I Mild steel, high strength mild steel, b. Type II Aluminum base alloys c. Type III Magnesium base alloys d. Type IV Corrosio
6、n resistant or stainless or low alloy steel (see 6.2). steel APPLICABLE DOCUMENTS 2.1 Non-Government publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of the documents which are DoD adopted are those listed in th
7、e issue of the DODISS cited in the solicitation. Unless otherwise specified, the issues of documents not listed in the DODISS are the issues of the documents cited in the solicitation (see 6.3). SOCIETY OF AUTOMOTIVE ENGINEERS, INC (SAE) AMs 3412 - Flux, Aluminum Brazing AMs 4375H - Magnesium Alloy
8、Sheet and Plate 3.0Al-1.OZn (AZ31B-O) Annealed and Recrystallized (AZ31B-H26) Cold Rolled and Partially Annealed AMs 4377F - Magnesium Alloy Sheet and Plate 1.OZn (AZ31B-H24) Cold Rolled, Partially Anne a 1 e d AMs 4376E - Magnesium Alloy Plate 3.0Al-1.OZn (Application for copies should be addressed
9、 to the Society of Automotive Engineers, Inc. 400 Commonwealth Drive, Warrendale, PA 15096.) AMERICAN WELDING SOCIETY, INC. (AWS) AWS WHB-1 CH6 - Symbols for Welding and Inspection AWS A3.0 - Welding Terms and Definitions Including Terms for Brazing, Soldering Thermal Spraying and Thermal Cutting 2
10、Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I MIL-W-4709LA TH W 9999906 0575770 2 M MIL-W-47091A (MI) AWS A5.1 - Carbon Steel Electrodes for Shielded AWS A5.2 - Carbon and Low Alloy Steel Rods for Metal Arch Welding, Specification for Oxyfuel Gas
11、 Welding, Specification for Electrodes, Specification for Welding Electrodes and Rods, Specification for AWS A5.19 - Magnesium Alloy Welding Rods and Bare Electrodes, Specification for AWS A5.5 - Low Alloy Steel Covered Arc Welding AWS 5.10 - Bare Aluminum and Aluminum Alloy (Application for copies
12、should be addressed to the American Welding Society, Inc. 550 N.W. LeJeune Road, P.O. Box 351040, Miami, FL 33135) (Non-Government standards and other publications are normally available from the organizations that prepare or distribute the documents. These documents also may be available in or thro
13、ugh libraries or other informational services.) 2.3 Order of precedence. In the event of a conflict between the text of this document and the references cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a sp
14、ecific exemption has been obtained. 3. REQUIREMENTS 3.1 Base metal preparation. 3.1.1 Cutting. The base metal may be cut by any of the accepted commercial practices such as shearing, torch cutting, or sawing in conformance with tolerance and edge conditions specified on the design drawing. a 3.1.2 E
15、dge preparation. Beveling, grooving, or other edge preparation shall be as specified on the design drawing in accordance with the symbols established in Chapter 6 of AWS WHB-1. 3.1.3 Weld surfaces. The base metal in the area to be welded shall be reasonably free from foreign materials such as dirt,
16、grease, paint, and heavy scale in accordance with high grade commercial practice for this class of work. Slug and loose scale 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-W-47091A TH 9999906 0575773 4 = MIL-W-470 91A (MI) on torch-cut edges
17、shall be removed by chipping, grinding, wire O brushing, or equivalent means. 3.1.4 Low alloy steel parts. Low alloy steel parts shall be preheated to 204 to 316O Celsius (C) immediately prior to welding. 3.1.5 Aluminum alloy parts. Aluminum alloy parts to be welded by the inert gas shielded arc met
18、hod shall be cleaned to remove all oil, grease, or other foreign matter and then etched to provide a surface free from oxide before welding. A typical etching solution may be prepared as noted below. the parts shall be thoroughly rinsed and dried. After etching, 3.1.5.1 Etching solution (typical) .
19、a. Sulfuric acid, 10% (percent) by volume b. Hydrofluoric acid, 1% by volume c. Water, 89% by volume d. Sodium dichromate, 17 pounds per 100 gallons solution 3.2 Welding methods. The following welding methods shall be used for each type of welding. The welding shall be done by hand except as otherwi
20、se provided herein (see 1.2). a. Type I (steel), metallic arc method, oxyacetylene, or inert gas shielded arc methods. b. Type II (aluminum alloy) oxyacetylene, oxyhydrogen or inert gas shielded arc methods. c. Type III (magnesium alloy) inert gas shielded arc method. d. Type IV (corrosion resistant
21、 steel) metallic arc or inert gas shielded arc methods. 3.2.1 Limitation on welding methods for steel. The inert gas shielded tungsten arc welding method or oxyacetylene welding method shall not be used for the welding of mild, high strength mild, or low alloy steel parts which are greater than 0.09
22、0 inches in thickness in the area to be welded. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-W-4709LA TH D 9999906 0575772 b D la 3.3.1.2 Rods for oxyacetylene welding. MIL-W-47 O 91A (MI) 3.2.2 Automatic welding. Automatic welding methods m
23、ay be used, subject to the approval of the Government inspector, provided the strength of the deposited weld metal is at least equal to that of the materials specified herein and the quality of welding conforms to the requirements of this specification. a 3.3 Welding materials. 3.3.1 Type I-steels.
24、3.3.1.1 Electrodes for metallic arc welding. 3.3.1.1.1 Electrodes for mild steel. For welding mild steel, electrodes conforming to AWS A5.5 and having a tensile st ength of not less than 60,000 pounds force per square inch (lbf/in ) as deposited shall be used. The electrodes shall be suitable for th
25、e intended use. 5 3.3.1.1.2 Electrodes for high strength mild steel and low alloy steel. For welding high strength mild steel and low alloy steel, electrodes conforming to AWS A5.5 and having a tensile strength of not less than 70,000 (lbf/in2) as deposited shall be used. The electrodes shall be sui
26、table for the intended use. 3.3.1.2.1 Rods for mild steel. For welding mild steel, rods I conforming to R45 of AWS A5.2 shall be used. 3.3.1.2.2 Rods for high strength mild steel and low alloy steel. For welding high strength mild steel and low alloy steel, rods conforming to R65 of AWS A5.2 shall b
27、e used. 3.3.1.3 Rods for inert gas shielded arc method. For welding mild, high strength mild, or low alloy steels, rods conforming to R100 of AWS A5.2 shall be used. 3.3.2 Type II welding aluminum alloys. 3.3.2.1 ER1100 bare wire. For butt welds and welding outside corners of 1100 and 3003 aluminum
28、alloys, ER1100 bare wire shall be used for all methods of welding as specified in AWS A5.10. 3.3.2.2 ER4043 bare wire. For welding aluminum alloys 5052, 6053, 6061, 443, and A356 (castings), and for welding all joints other than butt joints or outside corners in 1100 or 3003 aluminum 5 Provided by I
29、HSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-W-47091A TH 7799906 0575773 8 W Mat er i a 1 s Manganese Silicon Other elements Magnesium alloys, ER4043 bare wire shall be used for all methods of welding as specified in AWS A5.10. 3.3.2.3 Gas welding flux. Fo
30、r oxyacetylene or oxyhydrogen welding of aluminum alloys, use aluminum gas welding flux specified in AMs 3412 or equivalent. Percent Not less than Not greater than 1.2 0.30 0.30 Rema i nde r 3.3.3 Type III welding magnesium alloys. 3.3.3.1 AZ31B and similar alloys. For welding magnesium alloys corre
31、sponding to or similar to those specified in AMS4375H, 4376E and 4377F, a magnesium alloy welding rod having the composition as specified in AWS A5.19 and Table I shall be used (see 6.2). TABLE I. Composition of Magnesium Alloy Welding Rods. I Mat er ia1 s Percent Not less than Not greater than Alum
32、inum Zinc Manganes e Si 1 icon Other elements Magnesium 2.5 0.7 0.20 Remainder 3.5 1.3 0.05 0.30 3.3.3.2 M-1 and similar alloys. For welding magnesium alloys corresponding to or similar to those specified in AMS4375H, 4376E and 4377F, a magnesium alloy welding rod having the composition as shown in
33、table II shall be used (see 6.2). TABLE II. M-1 Magnesium Rod Composition. 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I MIL-U-47071A TH m 9979906 0575774 T MIL-W-47 O 91A (MI) 3.5 Cleaning of welds. O 3.3.4 Type IV welding corrosion resistant
34、steel. 3.3.4.1 Electrodes for metallic arc welding. For welding AISI types 347 and 321 or equivalent corrosion resistant or stainless steel by the metallic arc method, electrodes shall be AISI type 347 stainless steel or equivalent. 3.3.4.2 Rod for inert gas shielded arc welding. For welding AISI ty
35、pes 347 and 321 or equivalent corrosion resistant or stainless steel by the inert gas shielded arc method, the rod shall be AISI type 347 bare wire. welds and direction of welding shall be as specified on the applicable design drawing in accordance with the symbols established in Chapter 6 of AWS WH
36、B-1. 3.4 Location and direction of welds. The location of the 3.5.1 Welds in steel. Completed welds in mild steel, high strength mild steel, low alloy steel, or corrosion resistant steel shall be thoroughly cleaned by chipping and wire brushing to remove scale and flux prior to subsequent operations
37、. 3.5.2 Gas welded aluminum parts. Gas welded aluminum alloy This may be accomplished by submerging the parts in 10% parts shall be defluxed by a suitable method immediately after welding. sulfuric acid solution for 20 to 30 minutes followed by a thorougn rinse in clean running water. 0 3.6 Penetrat
38、ion. Penetration of fillet welds when cross- sectioned and examined as specified herein shall equal 15 to 25% of the base metal thickness in material of not less than 0.25 inch thick. In material greater than 0.25 inch thick, penetration shall be not less than 0.0625 inch. Butt welded joints shall h
39、ave 100% penetration unless partial penetration is permitted by symbol call out. 3.7 Workmanship. Workmanship shall be in accordance with high grade commercial practice covering this class of work. beads shall be reasonably smooth and uniform. Evidence of excessive undercutting cold laps, porosity b
40、low holes, cracks or slag inclusion shall be cause for rejection. Weld 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-W-47091A TH = 9999906 0575775 1 W MIL-W-47 O 91A (MI) 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for inspection. Unle
41、ss otherwise specified in the contract or purchase order, the contractor is responsible for the performance of all inspection requirements (examinations and tests) as specified herein. Except as otherwise specified in the contract or purchase order, the contractor may use his own or any other facili
42、ties suitable for the performance of the inspection requirements specified herein, unless disapproved by the Government. The Government reserves the right to perform any of the inspections set forth in this specification where such inspections are deemed necessary to ensure supplies and services con
43、form to prescribed requirements. 4.1.1 Responsibility for compliance. All items shall meet all requirements of sections 3 and 5. The inspection set forth in this specification shall become a part of the contractors overall inspection system or quality program. The absence of any inspection requireme
44、nts in the specification shall not relieve the contractor of the responsibility of ensuring that all products or supplies submitted to the Government for acceptance comply with all requirements of the contract. Sampling inspection, as part of manufacturing operations, is an acceptable practice to as
45、certain conformance to requirements, however, this does not authorize submission of known defective material, either indicated or actual, nor does it commit the Government to accept defective material. 4.2 - Lot. For purposes of acceptance, a lot of metallic parts welded under this specification sha
46、ll consist of all the units of a single production order submitted for inspection at one time. 4.3 Sampling. For purposes of inspection, sampling shall be performed in accordance with table III. 8 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-I e L
47、ot Size MIL-U-4709LA TH D 9997906 O575776 3 Sample Size MIL-W-47 O 91A (MI ) I 5. PREPARATION FOR DELIVERY I This section is not applicable to this specification. 2 to 4 to 26 to 51 to 91 to 151 to 281 to 501 to 1201 to 3201 to I 6. NOTES 3 25 50 90 150 280 500 1200 3200 10,000 10,001 and over I 100
48、% 3 5 6 7 10 11 15 18 22 29 In all cases: Acceptance number is ZERO Rejection number is ONE 4.4 Inspection. Inspection of the welded parts shall be by visual examination to determine compliance with the requirements of this specification. At the discretion of the Government Inspector, sample weldmen
49、ts representative of the production work of any welder may be required to permit evaluation of compliance with the requirements of this specification. Samples of fillet welds submitted for determining penetration shall be cross-sectioned, polished and etched by a method acceptable to the Government inspector. In addition, magnetic particle inspection shall be conducted on such welds and by such methods specified on the de
