1、1 # MIL-V-L35bB H 99q990b LYBL29 3TT I INCH-POUND I MIL-V-8 1356B(AS) 2 November 1992 SUPERSEDING 3 December 1975 MIL-V-8 1356A(AS) MILITARY SPECIFICATION VALVE, FUEL SYSTEM PRESSURIZATION AND VENT This specification is approved for use within the Naval Air Systems Command, Department of the Navy, a
2、nd is available for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scow. This specification covers one type of valve assembly for use in aircraft fuel tanks to sense and relieve positive or negative tank pressures and control pressurization and venting of the tank dur
3、ing fuel transfer and refueling operations. 2. APPLICABLE DOCUMENTS 2.1 Government Documents. 2.1.1 SDecifications and Standards. The following documents form a part of this specification to the extent described herein. Unless otherwise specified, the issues of these documents are those listed in th
4、e issue of the Department of Defense Index of Specifications and Standards (DODISS) and supplement thereto, cited in the solicitation (see 6.2). SPECIFICATIONS FEDERAL TT-s-735 Standard Test Fluids; Hydrocarbons Military DOD-D- 1000 MIL-T-5624 MIL-C-7024 MIL-S-7742 Drawings, Engineering and Associat
5、ed Lists Turbine Fuel, Aviation, Grades JP-4, JP-5 and JP-5/JP-8 ST Calibrating Fluid, Aircraft Fuel System Components Screw Threads, Standard, Optimum Selected Series, General Specification for Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in
6、 improving this document should be addressed to: Naval Air Systems Command, AIR-5363, Washington, DC 20361-5360, by using the Standardization Document Improvement Proposal (DD Form 1426) or by letter. AMSC N/A Fsc 4820 DISTRTRUTION STATEMENT A, Approved for public release; distribution is unlimited.
7、 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-8135bB m 9999906 1489130 O11 m MIL-V-81356B(AS) MIL-S-8879 MIL-N-25027 STANDARDS Military MIL-STD- 129 MIL-STD- 130 MIL-STD-480 MIL-STD-810 MIL-STD-889 MIL-STD- 1523 MIL-STD-2073- 1 MS20995 MS335
8、40 MS33588 MS33649 Screw Threads, Controlled Radius Root with Increased Minor Diameter; General Specification for Nut, Self-Locking, 250“F, 450F and 800F Marking for Shipment and Storage Identification Marking of U.S. Military Property Configuration Control - Engineering Changes, Deviations and Waiv
9、ers. Environmental Test Methods and Engineering Guidelines Dissimilar Metals Age Controls of Age-Sensitive Elastomeric Material (for Aerospace Applications) DOD Materiel Procedures for Development and Application of Packaging Requirements Wire, Safety or Lock Safety Wiring and Cotter Pinning, Genera
10、l Practices for Nuts, Self-Locking, Aircraft, Reliability and Maintainability, Usage Requirements For Bosses, Fluid Connection-Intemal Straight Thread (Unless otherwise indicated, copies of federal and military specifications and standards are available from the Standardization Documents Order Desk,
11、 Bldg. 4D, 700 Robbins Avenue, Philadelphia, PA 191 11-5094.) 2.2 Non-Government publications. The following documents form a part of this specification to the extent specified herein. Unless otherwise specified, the issues of the documents which are DOD adopted shall be those listed in the issue of
12、 the DODISS specified in the solicitation. Unless otherwise specified, the issues of documents not listed in the DODISS shall be the issue of the nongovernment documents which is current on the date of the solicitation (see 6.2). SOCIETY OF AUTOMOTIVE ENGINEERS, INC. SAE AS568 Aerospace Size Standar
13、d For O-Rings (Requests for copies should be addressed to the Society of Automotive Engineers, Inc., 400 Commonwealth Drive, Warrendale, PA 15096.) 2.2 Order of Precedence. In the event of a conflict between the text of this document and the references cited herein (except for MS standards), the tex
14、t of this document takes precedence. Nothing in this specification supersedes applicable laws and regulations unless a specific exemption has been obtained. 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-8L35bB 99999Ob LY89L3L T58 MIL-V-8135
15、6B(AS) 3. REQUIREMENTS 3.1 Oualification. The valve furnished under this specification shall be a product which is authorized by the qualifying activity for listing on the applicable qualified products list (QPL) at the time set for opening of bids. (See 6.3) 3.2 Reliabilitv. The valve shall withsta
16、nd strains, jars, shocks, vibrations, and other conditions incident to installation and service use. All parts of the valve shall be adequately secured to ensure its continued integrity and retention of performance (see 3.6) within prescribed limits during normal shipment and service operation. 3.2.
17、1 Valve Life. The valve shall be designed to withstand 10,OOo endurance cycles which simulate conditions of use, as described in paragraph 4.6.5. 3.2.2 Strength. As evidence of structural soundness, the valve will be subjected to: a. Air pressure of 75 psi applied to the bleed port. b. Accelerations
18、 of 8.59 g forward, 7.75 g rearward, and 10.00 g downward. c. Impact shocks of 30 g each with 11 millisecond duration. 3.2.3 Vibration. The valve shall withstand vibrations from 5 to 200 Hz, Resonance and Cycling, as described in paragraph 4.6.8. 3.3 Materials. Materials and processes used in the ma
19、nufacture of the valve shall conform to applicable Government specifications. Materials conforming to contractor or industry specifications may be used provided adequate testing is performed to meet the performance requirements of this specification. Use of contractor or industry specifications shal
20、l not constitute waiver of Government inspection. All materials used in the valve shall be resistant to MIL-T-5624 fluids having an aromatic content from O to 30 percent. 3.3.1 Metals. All metals that are not of a corrosion-resistant type shall be suitably protected to resist corrosion during the no
21、rmal service life of the valve. Use of dissimilar metals as defined by MIL-STD-889, especially steel in contact with aluminum or aluminum alloys, shall be avoided where practicable. Magnesium, cadmium, copper and copper alloys shall not be I Used. 3.3.2 Elastomers. Elastomeric parts, such as O-rings
22、 and diaphragms shall be of materials compatible with the requirements of the fuel resistance and extreme temperature test (see 4.6.4) and acceptance test (see 4.5.2). 3.3.2.1 Age Controls. Age sensitive elastomeric materials controlled by MIL-STD-1523, shall not be used. 3 Provided by IHSNot for Re
23、saleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-BL356B m 9999906 I1489132 994 m . MIL-V-8 1356B(AS) 3.3.3 Finish. Anodizing, plating, and protective treatments shall be such that the finish will not chip, crack, or cause the fuel or fuel system to be affected in any wa
24、y. Paint and cadmium plating shall not be used. 3.4 Design and Construction. The design and construction of the valve shall be such that disassembly and replacement of parts can be accomplished without use of special tools. Installation characteristics and envelope dimensions shall be as shown in Fi
25、gure 1. 3.4.1 Threaded Connections. 3.4.1.1 . Female threaded connections for tube fittings shall conform to MS336-49. All other female threaded connections in aluminum alloys used for installation and inspection shall have steel inserts, the internal threads conforming to the requirements of MIL-S-
26、7742 or MIL-S-8879. 3.4.1.2 Pipe Threads. Pipe threads shall not be used except for permanent closures. 3.4.2 Securin- Hardware. Where threaded fasteners, pins, and other methods are used to secure parts of the valve, they shall be safetied by means of self-locking nuts, cotter pins, lockwashers, re
27、taining rings, or safety wire. Safety wire shall conform to MS20995 and be installed in accordance with MS33540. Self locking nuts shall conform to MIL-N-25027 and be used in accordance with MS33588. 3.4.3 O-rings. O-ring sizes shall be as per SAE AS568. 3.4.4 Weight. Component weight shall not exce
28、ed 2.7 pounds. 3.4.5 Changes. Changes in design or construction subsequent to qualification approval shall be processed in accordance with MIL-STD-480. 3.5 Main tainabil i ty. 3.5.1 InterchanPeability. All valves having the same manufacturers part number shall be completely interchangeable with resp
29、ect to installation and performance. It shall be the responsibility of the valve manufacturer to prepare specifications or source control drawings for purchased parts to ensure that production valves are the same as the qualification valve. 3.5.2 Ad-iustments. After assembly and delivery to the proc
30、uring activity, the valve shall not require any adjustments in order to function properly. It is intended that this valve is not to be serviced in the fleet. 3.6 Performance Characteristics. When installed in a fuel tank, the valve shall meet the following performance requirements (test descriptions
31、 are based on a float activated valve): NOTE: Unless otherwise specified, all pressures are static gage. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-8135bB D 9999906 1489133 820 MIL-V-8 1356B(AS) MOUNTING SURFACE SHUT-OFF 1 I I 4.56 Li- D
32、IA TYP GROOVE FOR AS568-115 PACKING 2 PLACES -250-28 UNF-3B THD SELF LOCKING INSERT 100 x .525 5 ,005 DIA CSK 2 PLACES .60-.75 LENGTH SCREW 1 I I II I 0.564 A/ PER MS 33649-6 A- BLEED AIR INLET FORT OVERBOARD AIR OUTLET FORT (VENT) PER MS 33649-16 0.38 “ES : DIMENSIONS IN INCHES. UNLESS OTHERWISE SP
33、ECIFIED, IOLERANCES: DECIMALS ANGULAR +-2O .xxx * .o10 .XX f .O3 Figure 1. Installation Characteristics and Envelope Dimensions 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-L35bB 999990b L489L34 767 MIL-V-81356B(AS) 3.6.1 Venting. a. b. C.
34、 d. 3.6.1.1 a. b. With float down and no pressure applied at the bleed air port, the inlet vent port (the inlet side of the Overboard vent system) shall open, and air shall pass through the valve and out the overboard outlet. Tank pressure necessary to attain full flow shall not exceed 2.0 psi. With
35、 float up, the inlet vent port shall be closed. With float down, application of air pressure of 3.0 through 20.0 psi to the bleed- air port shall close the inlet vent port allowing bleed air flow into the tank, but not overboard through the vent system except for trickle flow through a relief orific
36、e (see 3.6.2.d). The inlet vent port shall remain closed as long as bleed air pressure equals or exceeds tank pressure, but shall reopen by the time bleed air pressure is reduced to 2 psi below tank pressure. With float down, with a flow of 30 scfm of air (see 6.4), the pressure drop through the val
37、ve from inlet vent to overboard outlet shall not exceed 2.0 psi. Attitude Vent Control. With the float uncovered and the aircraft in a 20“ through 60“ climb attitude, or a 20“ through 45“ dive attitude, and a O“ through f 15“ roll angle, the inlet vent port shall close to prevent fuel from flowing o
38、ut of the vent line. To prevent spillage through the overboard vent system during catapult launch with a full or partially filled tank, the valve shall hold the inlet vent port closed at all forward accelerations to a maximum of 8.593 when tested in accordance with 4.6.7.2, (see 6.4). 3.6.2 Pressuri
39、zing. a. With float down, application of an increasing or stable air pressure of 3.0 through 20.0 psi through the bleed-air port shall close the vent port. Steady state tank pressure shall be not more than 0.5 psi below bleed-air pressure. NOTE: Tank pressurization must also occur with float up - ta
40、nk full. b. With float down and tank vented to atmosphere, an air pressure of 0.7 psi applied to the bleed-air port shall cause a flow of not less than 2.4 scfm. c. The valve assembly shall not be damaged by application of 75 psi pressure for two minutes on the bleed-air pressure port. . a O a 6 Pro
41、vided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-n U U d II O c-4 CL W E v U U . W c3 e Y 4 W il IL-V-8 l1$5 bB m 99999Ob 1489135 bT3 m MIL-V-8 1356B(AS) 2 Q Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-
42、,-MIL-V-8135bB = 9999906 1489136 53T = MIL-V-8 1356B(AS) d. If the valve is pressurized through the bleed-air port, closing the bleed air supply line shall not trap air. The air shall dissipate, and the inlet vent port shall reopen. If a diaphragm actuated valve is used to control venting and pressu
43、rizing, the bleed-air side of the diaphragm may be vented to the overboard outlet through an orifice or equivalent opening. 3.6.3 External Leakage. a. With fuel at vent shut-off level (1.61 i 0.39 inches from the top of the valve), fuel leakage to overboard port shall not exceed the limits of Figure
44、 2. b. With the valve submerged to the mounting surface, and with the tank pressurized to 13 psi by means other than through the bleed-air line, leakage in the reverse direction through the bleed-air port shall not exceed five drops per minute. c. With the valve submerged to the mounting surface, fu
45、el leakage to overboard shall not exceed the limits of Figure 2. 3.6.4 Shut-off and ReomninP Levels. a. At all rising fuel levels below vent shut-off level, the inlet vent port shall be open to overboard. (See 3.6.3.a and Figure 1) b. At all fuel levels above vent shut-off level with tank pressure a
46、t any value from zero up to relief valve cracking pressure, the inlet vent port shall be closed. c. Under conditions of falling fuel level and no bleed-air pressure applied, the inlet vent port shall reopen within 0.5 inches of the closing level determined in 3.6.4.a. 3.6.5 Pressure Relief Valve Ass
47、embly. The assembly shall incorporate a pressure relief valve set to relieve tank pressure at 40 to 50 psi, and shall be capable of flowing 50 scfm of air with a maximum tank pressure of 50 psi. 3.6.6 Suction Relief. The assembly shall incorporate a suction relief valve capable of flowing 80 scfm fr
48、om the overboard outlet port into the tank with a maximum pressure drop of 3.5 psi. 3.7 Environmental Conditions. The valve shall withstand the fuel and air temperatures for the time periods listed in Table I: 8 Provided by IHSNot for ResaleNo reproduction or networking permitted without license fro
49、m IHS-,-,-MIL-V-L35bB = 99999Ob 1489137 476 Environmental Fluid Temperature (OF) -65 to + 160 +220 + 240 -65 to +250 + 350 Ambient Air Pressurization Air Fuel -40 to + 135 Exposure Period Continuous 30 Minutes 2% Minutes Continuous 30 Minutes Continuous 3.8 Identification of Product. Assemblies and parts shall be marked for identification in The following information shall be marked on the valve accordance with MIL-S
