1、 INCH-POUND MIL-DTL-87255A(USAF) 6 June 2008 SUPERSEDING MIL-V-87255 (USAF) 31 December 1990 DETAIL SPECIFICATION VALVES, PRESSURE, ANTI-G SUIT, HIGH FLOW This specification is approved for use by the Department of the Air Force, and is available for use by all Departments and Agencies of the Depart
2、ment of Defense. MIL-DTL-87255 (USAF) is inactive for new design and is no longer used, except for replacement purposes. 1. SCOPE 1.1 Scope. This specification covers a high-flow, pressure regulating valve for inflating anti-G suits and providing a sense line signal for a g-compensated oxygen regula
3、tor (if applicable). It also includes details of inlet and outlet fittings required to interface the valve to specific aircraft. 1.2 Classification. The designations for the three valves are as follows: a. VAU-45(V)1/A b. VAU-45(V)2/A c. VAU-45(V)3/A Comments, suggestions, or questions on this docum
4、ent should be addressed to ASC/ENRS, 2530 Loop Road West, Wright-Patterson AFB OH 45433-7101 or emailed to Engineering.Standardswpafb.af.mil. Since contact information can change, you may want to verify the currency of this address information using the ASSIST Online database at http:/assist.daps.dl
5、a.mil. AMSC N/A FSC 1660 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-87255A(USAF) 2 2. APPLICABLE DOCUMENTS 2.1 General The documents listed in this section
6、 are specified in sections 3, 4, or 5 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are ca
7、utioned that they must meet all specified requirements of documents cited in sections 3, 4, or 5 of this specification, whether or not they are listed. 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a part of this
8、 document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. COMMERCIAL ITEM DESCRIPTIONS A-A-59503 Nitrogen, Technical DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-S-7742 Screw Threads, Standard, Optimum Selected Se
9、ries: General Specification For (Inactive for New Design) DEPARTMENT OF DEFENSE STANDARDS MIL-STD-130 Identification Marking of U.S. Military Property MIL-STD-810 Environmental Test Methods and Engineering Guidelines MIL-STD-889 Dissimilar Metals MIL-STD-1916 DoD Preferred Methods for Acceptance of
10、Product (Copies of these documents are available online at http:/assist.daps.dla.mil/quicksearch/ or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia PA 19111-5094.) 2.3 Non-Government publications. The following documents form a part of this document to th
11、e extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. AMERICAN SOCIETY OF MECHANICAL ENGINEERS (ASME) ASME Y14.100 Engineering Drawing and Related Documentation Practices (Copies of this document are available online at
12、http:/www.asme.org or from ASME, P.O. Box 2300, Fairfield, NJ 07007-2300.) Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-87255A(USAF) 3 AMERICAN SOCIETY FOR QUALITY (ASQ) ANSI/ASQ Z1.4 Sampling Procedures and Tables for Inspection by Attrib
13、utes (DoD Adopted) (Copies of this document are available online at www.asq.org or from the American Society for Quality, 600 North Plankinton Ave., Milwaukee WI 53203-2914.) SAE INTERNATIONAL SAE AS 4395 Fitting End, Flared, Tube Connection, Design Standard (DoD Adopted) SAE AS 5132 Fitting End-Hos
14、e Connection, Design Standard (DoD Adopted) (Copies of these documents are available online at http:/www.sae.org or from SAE International, 400 Commonwealth Dr., Warrendale, PA 15096-0001.) 2.4 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between
15、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 specific exemption has been obtained. 3. REQUIREMENTS 3.1 First article. When specified (see 6.2), a sample sh
16、all be subjected to first article inspection in accordance with 4.2. 3.2 Material. Materials shall conform to applicable specifications and standards as specified herein and on applicable drawings. Materials which are not covered by specifications and standards, or specifically described herein, sha
17、ll be reported to the acquisition activity and shall require contracting officer approval prior to use. Materials shall be of the best quality, of the lightest practical weight, and suitable for the purpose intended. 3.2.1 Recycled, recovered, or environmentally preferable materials. Recycled, recov
18、ered, or environmentally preferable materials should be used to the maximum extent possible, provided that the material meets or exceeds the operational and maintenance requirements, and promotes economically advantageous life cycle costs. 3.2.2 Metal parts. All metal parts shall be of a corrosion-r
19、esistant material or treated in a manner to render them adequately resistant to corrosion. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-87255A(USAF) 4 3.2.2.1 Dissimilar metals. Unless protected against electrolytic corrosion, dissimilar m
20、etals as defined in MIL-STD-889 shall not be used in intimate contact with each other. 3.2.3 Nonmetallic materials. Any nonmetallic material that is adversely affected by continued use with air shall not be used. 3.2.3.1 Elastomer components. Elastomer components, except silicone, shall be not more
21、than 12 months old from the date of manufacture to the date of delivery to any government service or to any airframe or accessory manufacturer. 3.2.4 Protective treatment. Materials shall be protected from deterioration in a manner that shall in no way prevent compliance with the performance require
22、ments of this specification. The valve shall resist corrosion and deterioration due to fuels, salt fog, microorganisms, moisture, hydraulic fluid, lubricating oils, grease, ozone, or atmospheric conditions likely to be encountered in storage or normal service. Protective coatings which might crack,
23、chip, or scale during normal service or storage life or under extremes of environmental conditions shall not be used. 3.3 Standard parts. Military standard parts shall be used when they suit the purpose. Use of non-standard parts requires contracting officer approval prior to use. 3.4 Design and con
24、struction. The valve shall be designed to pass air at a regulated pressure to the aircrew members anti-G suit and to the sense line of the regulator (if applicable) and shall contain provisions for suit exhaust. The valve shall include provision for inlet and outlet fittings that incorporate swivel
25、features. The fittings shall have a diameter and finish compatible with the aircraft inlet hose, anti-g suit delivery hose, and the outlet pressure sense line (if applicable). The outlet fitting shall be in accordance with figures 1, 2 or 3, as required. The outlet pressure shall be a function of th
26、e acceleration force applied to the valve in the +Gz (see 6.4.1) direction. The design shall enable manual operation (press-to-test) of the valve and shall provide means to simulate acceleration forces (see 3.8.2 and 4.4.2). The valve shall be designed to perform as specified in 3.5. Moisture in the
27、 air source to the valve shall not adversely affect operation of the valve. 3.4.1 Installation. The valve shall be designed such that it can be properly installed in the applicable aircraft. This includes proper alignment with the mounting brackets and connections with the inlet and outlet hoses. Th
28、e existing control panels shall also be accommodated. There shall be no interference with aircraft structure. Minimum requirements for installation are given on figures 1, 2, and 3. Proper installation shall be demonstrated as specified in 4.5.1.1.1. Should there be a conflict between the installati
29、on demonstration specified in this document and figures 1, 2, and 3, the installation demonstration shall take precedence. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-87255A(USAF) 5 3.4.2 Relief valve. The valve shall include a pressure r
30、elief valve that shall not allow the valve outlet pressure to the anti-g suit and the sense line (if applicable) to exceed 13 psig. 3.4.3 Lubrication. The valve shall be designed and constructed in such a manner that no maintenance lubrication shall be required. 3.4.4 Inlet screen. The valve shall c
31、ontain a corrosion-resistant steel, 30 by 30 maximum mesh, 0.010 inch minimum wire diameter inlet screen. All inlet air shall pass through the screen. 3.5 Performance. All specified performance requirements shall be based on the use of air. 3.5.1 Minimum operating acceleration force. The minimum equ
32、ivalent acceleration force required to open the valve to permit flow of 0.01 liter per minute shall be between 1.25 and 1.50 Gz (see 4.5.2). 3.5.2 Outlet pressure regulation. For a constant applied acceleration force, the outlet pressure schedule during testing (see 4.5.3) shall be within the range
33、specified in table I and displayed graphically on figure 4 for both gradual onset/offset ( 9.33 - 11.00 1.25 4.00 1.45 +Gz 1.80 - 4.00 10.00 1.50 +Gz 2.00 - 10.00 13.00 - 3.5.3 Leakage. The leakage to the ambient shall not exceed 1.0 liters per minute. There shall be no leakage to the outlet (see 4.
34、5.4). Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-87255A(USAF) 6 NOTES: 1. Dimensions are in inches. 2. MS33656 has been cancelled. Future acquisitions for this material should refer to SAE AS4395. 3. MIL-S-7742 is Inactive for New Design
35、. FIGURE 1. Aircraft interface dimensions for VAU-45(V)1/A. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-87255A(USAF) 7 NOTES: 1. Dimensions are in inches. 2. MS33656 has been cancelled. Future acquisitions for this material should refer t
36、o SAE AS4395. 3. MIL-S-7742 is Inactive for New Design. FIGURE 2. Aircraft interface dimensions for VAU-45(V)2/A. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-87255A(USAF) 8 NOTES: 1. Dimensions are in inches. 2. MS33656 and MS33658 have b
37、een cancelled. Future acquisitions for this material should refer to SAE AS4395 and SAE AS5132, respectively. 3. MIL-S-7742 is Inactive for New Design. FIGURE 3. Aircraft interface dimensions for VAU-45(V)-3/A.Provided by IHSNot for ResaleNo reproduction or networking permitted without license from
38、IHS-,-,-MIL-DTL-87255A(USAF) 9 FIGURE 4. Anti-g valve outlet pressure vs Gz. 3.5.4 Anti-chatter. The valve shall not chatter (see 4.5.5 and 6.4.2). 3.5.5 Outlet pressure response 3.5.5.1 Response time. When the acceleration force is being applied by a centrifuge or an aircraft, the outlet pressure s
39、hall be in accordance with table I (see figure 4) within 2 seconds after the application of the force. When the acceleration force is being decreased, the pressure shall be in accordance with table I (see figure 4) within 5 seconds after decreasing the force. Additionally, the outlet pressure shall
40、change in a smooth continuous manner without oscillations or step responses. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-87255A(USAF) 10 3.5.5.2 Test limit response time. During testing using a step response input to simulate the G force
41、the tank pressure shall have the response time given by table II (see 4.5.6). 3.5.6 High temperature exposure. The valve shall operate satisfactorily after completion of the high temperature test at 250 5 F (see 4.5.7). 3.5.7 Low temperature exposure. The valve shall operate satisfactorily after com
42、pletion of the low temperature test at -65 5 F (see 4.5.8). 3.5.8 Vibration. The valve shall operate satisfactorily and shall show no evidence of mechanical or material failure after completion of the vibration tests (see 4.5.9). 3.5.9 Salt fog. The valve shall show no evidence of corrosion of mecha
43、nical failure after completion of the salt fog test (see 4.5.10). 3.5.10 Internal corrosion. The valve shall show no evidence of corrosion of mechanical failure after completion of the salt fog test (see 4.5.11). 3.5.11 Centrifuge testing. This testing shall be done using valves of the same design a
44、s those that passed all other performance tests in 3.5. Centrifuge testing shall include an anti-chatter test and performance testing (see 4.5.12). 3.5.12 Endurance. The valve shall have a mean-cycle-between-failure of 15,030 cycles (see 6.4.3) and shall pass the endurance test (see 4.5.13). 3.5.13
45、Disassembly and examination. The valve shall not show excessive evidence of deterioration or wear due to testing which might affect the valve performance (see 4.5.14). 3.6 Interchangeability. All parts having the same manufacturers part number shall be functionally and dimensionally interchangeable
46、with each other with respect to installation and performance. The item identification and part number requirements of ASME Y14.100 shall apply. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-87255A(USAF) 11 TABLE II. Test response time. Forc
47、e Applied From Tank Pressure Response Time (Max) 1 to 10 Gz As specified on figure 4 for 10 Gz 1.6 sec 10 to 1 Gz 0 2.7 sec 1 to 6 Gz As specified on figure 4 for 6 Gz 1.6 sec 6 to 1 Gz 0 2.2 sec 3.7 Weight. The total weight of the valve shall not exceed 3 pounds. 3.8 Identification of product. The
48、valve shall be marked for identification in accordance with MIL-STD-130 and shall include at least the following information: Valve, Pressure, Anti-G Suit, 1/ Manufacturers Part No. Manufacturers Identification U.S. MXXXXX-X (see 6.5) Date of Manufacture: MFD (Month)(Year) 2/ 1/ Enter the applicable designation (VAU-45(V)1/A, VAU-45(V)2/A, or VAU-45(V)3/A here. 2/ The manufactured date may be stamped on the valve rather than marked on the nameplate and shall be as permanent as the normal life expectancy of the valve. 3.8.1 Ports. All inlet and outlet ports shall be clearly identi
