1、- s. T MIL-G-25520B 66 = 9979906 O474678 2 I INCH-POUND I MI L-G-25520B(AS) 15 April 1991 SUPERSEDING MIL-G-25520A(USAF) 4 March 1957 MILITARY SPECIFICATION GAGE, PRESSURE, DIAL INDICATION, OXYGEN 0-500 PSI, TYPE MF-3 This specification is approved for use within the Naval Air Systems Command, Depar
2、tment of the Navy, and is available for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers a 1 1/2 inch round dial, low pressure oxygen system pressure gage (range 0-500 psi). 2. APPLICABLE DOCUMENTS O 2.1 Government documents. 2.1.1 Speci
3、fications, standards, and handbooks. The following specifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those listed in the issue of the Department of Defense Index of Specifications and St
4、andards (DODISS) and supplement thereto, cited in the solicitation (see 6.2b). SPECIFICATIONS FEDERAL BB-A-1034 - Ai r, Compressed, for Breath! ng Purposes. BB-N-411 - Ni trogen, Technical. Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in impr
5、oving this document should be addressed to: Engineering and Standardization Department (Code 531, Naval Air Engi neering Center, Lakehurst, NJ 08733-5100, by using the Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter. Systems 0 AMSC NIA
6、FSC 6685 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-G-25520B bb 9997906 0474679 4 M PPP-6-601 - Boxes, Wood, C1 eated-Plywood PPP-B-62 1 - Boxes, Wood, Nailed
7、and Lock-Corner PPP-6-636 - Boxes, Shi ppi ng, Fi berboard P P P- B- 640 - Boxes, Fi berboard, Corrugated, Tri pl e-Wal 1 MILITARY MIL-P-116 - Preservation, Methods of MIL-P-7105 - Pipe Threads, Taper, Aeronautical National Form, Symbol ANPT, General Requirements for STANDARDS FEDERAL FED-STD-H28/2
8、- Unified Inch Screw Threads, UN and UNR Thread Forms M I L I TARY MIL-STD-105 - Sampling Procedures and Tables for Inspection by MIL-STD-129 - Marking for Shipment and Storage MIL-STD-130 - Identification Marking of U.S Military Property MI L-STD-889 - Di s s i mi 1 ar Me tal s MIL-STD-1359 - Clean
9、ing Methods and Procedures for Breathing MS33558 - Numerals and Letters, Aircraft Instrument Dial (Unless otherwise indicated, copies of the federal and military specifica- Attributes Oxygen Equipment Standard Form of tions, standards, and handbooks are available from the Standardization Documents O
10、rder Desk, Building 4D, 700 Robbins Avenue, Philadelphia, PA 19111-5094. 2.2 Non-Government publications. The following document forms a part of this document to the extent specified herein. Unless otherwise specified, the issues of the documents which are O00 adopted are those listed in the issue o
11、f 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 6.2b). AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI) ANSI 640.1-85 - Gauges, Pressure and Vacuum, Indicating Dial Type-El
12、astic Element 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- MIL-G-2552UB 66 9997906 Oq74680 O m (Application for copies should be addressed to the American National Standards, Institute, 1430 Broadway, New York, NY 10018-3308,) (Non-Government s
13、tandards and other publications are normally available from the organizations that prepare or distribute the documents. may be available in or through libraries or other informational services.) These documents also 2.3 Order of precedence. In the event of a conflict between the text of this documen
14、t 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 6.21, a sample shall be subjected to first
15、 article inspection (see 6.4) in accordance with 4.3. 3.2 Materials. Materials shall conform to applicable specifications and shall be as specified herein and on applicable drawings. Materials which are not covered by specifications, or which are not specifically described herein, shall be of the li
16、ghtest practicable weight, and suitable for the purpose intended. 3.2.1 Metals. Metals shall be of the corrosion-resistant type or suitably treated to resist corrosion due to oxygen, salt spray, or atmospheric conditions likely to be met in storage or normal service. 3.2.1.1 Dissimilar metals. Unles
17、s suitably protected against electrolytic corrosion, dissimilar metals shall not be used in intimate contact with each other. Dissimilar metals are defined in MIL-STD-889. 3.2.3 Nonferrous. Nonferrous materials shall be used for all parts of the gage except where ferrous materials are essential and
18、do not come in direct contact with the oxygen. 3.2.4 Nonmagnetic. Nonmagnetic materials shall be used for all parts of the gage except where magnetic materials are essential. 3.2.5 Protective treatment. When materials are used in the construction of the gage that are subject to deterioration when ex
19、posed to environmental conditions likely to occur during service usage, they shall be protected against such deterioration in a manner that will in no way prevent compliance with the performance requirements of this specification. Protective coating which might crack, chip, or-scale during normal se
20、rvice life or under extremes of environmental conditions shall not be used. 3.3 Standard parts. 3.4 ANSI standard. The gage shall conform to ANSI B40.1-85. MS and AN standard parts shall be used where they suit the purpose. 3 Provided by IHSNot for ResaleNo reproduction or networking permitted witho
21、ut license from IHS-,-,-MIL-G-25520B 66 M 9979906 O474683 2 , 3.5 Design and construction. The gage shall be designed and constructed so that no part will work loose in service. They shall be leakproof, and shall be bui 1 t to withstand without fai lure the strains, jars, vibrations, and other condi
22、tions incident to shipping, storage, installations, and service. Any pivots, bearings, gears or other moving parts shall neither bind nor shake, and shall be as near frictionless as practicable. repairs can be easily made by the personnel of the operating units without the aid of special tool s. The
23、 gages shall be so designed that minor 3.5.1 Case. The case shall be in accordance with Figure 1. The case shall be made of either nonferrous low-density metal or a synthetic material and shall have a smooth surface with a durable dull black finish. The synthetic material shall be of the thermal-set
24、ting type. prevent damage to the gage mechanism under conditions incident to shipping, storage, installation and service. The case shall be of a durable construction to 3.5.2 Bosses. The bosses shall be as shown in figure 1. Wrench flats shall be provided on the sides of the boss. 3.5.3 Operating me
25、chanism. The indicating and the pressure elements shall comprise a unit distinct from the case. This unit shall be sufficiently rugged in order that small distorations of the case will not affect the accuracy of the i nd i cat i on s. correct the indications during the service life of the gage. Adju
26、stment shall require no special tools. 3.5.3.1 Gage adjustment. The gage shall be provided with a means to adjust or 3.5.4 Dial. The dial shall be held securely in such a manner that it will not loosen or turn when the gage is vibrated. If screws are used to attach the dial plate, they shall be so l
27、ocated that they will not interfere with any dial marking or prevent locating any dial marking in the proper location. 3.5.4.1 Dial face. The dial face shall be as shown in figure 2. 3,5,5 Pointer. The pointer shall be in accordance with figure 3. It shall be light and sufficient rigid to prevent os
28、cillation under vibration, and shall be free to swing beyond either end of the range without being engaged by a mechanical stop. Suitable stops shall be incorporated within the mechanism to prevent disengagement if possible due to operating mechanism design. The pointer shall be of such length as to
29、 touch but never overlap the graduations on the dial face. indicating end of the pointer shall be painted white. 3.5.5.1 Overpressure stop. An overpressure stop shall be provided on the gage, designed in such a manner as to restrain the mechanism rather that the pointer. The overpressure stop shall
30、allow pointer travel beyond full scale, 525 * 25 Dsi. The 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3 3 MIL-G-25520B 66 = 9999906 0474682 4 MIL-G-255208(AS) 3.5.5.2 Hair springs. Hair springs, if used, shall be made from phosphor a bronze. 3.
31、5.6 Surge pressure restriction. A restriction of 0.020 inch diameter shall 3.6 Performance. be provided between the gage connection and the gage mechanism. 3.6.1 Vi sua1 examination and dimensional check. 3.6.1.1 Visual examination. When visually examined as specified in 4.6.1.1, the gage shall conf
32、orm to the requirements of this specificatiori. enumerate the defects. Table IV, 9 Classification of Defects for Visual Examination, shall be used to classify and 3.6.1.2 Dimensional check. When dimensionally checked as specified in 4.6.1.2, the gage shall conform to the requirements of figures 1, 2
33、, and 3. Any measurement deviating from the specified dimensions and tolerances shall be classified as a dimensional defect. 3.6.2 Scale error (room temperature). When tested as specified in 4.6.2, the gage pressure readings shall be within the scale tolerance specified in Table I. 4.6.3, shall not
34、exceed the tolerance specified in Table I. 3.6.3 Friction. The friction error of the gage, when tested as specified in o 3.6.4 Leakage. The pressure readings of the gage, when tested as specified in 4.6.4, shall be the same. 3.6.5 Low temperature and cold resistance. The gage when tested as specifie
35、d in 4.6.5, shall show no evidence of material failure and the qaqe iointer shall -“ * move smothly throughout the entire range of travel. scale error and friction test points shall not differ from those obtained in the original tests by more than f 20 psi from O to 100 psi or * 50 psi from 100 to 5
36、00 psi. The pressure readings for the 3.6.6 High temperature. The gage, when tested as specified in 4.6.6, shall not show any evidence of material failure. The pressure readings for the scale error test points shall not differ from those obtained in the original scale error (room temperature) test b
37、y more than I 10 psi from O to 100 psi or i 25 psi from 100 to 500 psi. 3.6.7 Vibration. The gage, when tested as specified in 4.6.7, shall not show any evidence of material failure and-the pressure readings for the scale error test points shall not differ from those obtained in the original scale e
38、rror (room temperature) test by more than * 10 psi from O to 100 psi or * 25 psi from 100 to 500 psi. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-G-25520B bb m 9999706 0474683 b MIL-G-25520B(AS) 3.6.8 Seasoning. The gage, when tested as spe
39、cified in 4.6.8, shall not show any evidence of material failure and the gage pressure readings shall not differ from those obtained in the original scale error (room temperature) and friction tests by more than 10 psi. 36.9 Overpressure. The gage, when tested as specified in 4.6.9, shall show no ev
40、idence of material failure and the pressure readings obtained in the scale error (room temperature) and friction tests shall not differ from those obtained in the original tests by more than * 10 psi from O to 100 psi or i 25 psi from 100 to 500 psi. 3.7 Threads. 3.7.1 Screw threads. Screw threads s
41、hall conform to FED-STD-H28/2. 3.7.2 Pipe threads. Pipe threads shall conform to MIL-P-7105. 3.8 Interchangeability. Al 1 parts having the same manufacturers part number shall be functionally and dimensionally interchangeable. 3.9 Weight. The weight of the gage shall not exceed 0.20 pounds. 3.10 Ide
42、ntification marking. The gage shall be marked in accordance with MIL-STD-130 and shall contain the following information: GAGE, PRESSURE, DIAL INDICATING, OXYGEN 0-500 PSI, Type MF-3 MANUFACTURERS IDENTIFICATION CONTRACT OR ORDER NO. MIL-G-25520 3.11 Cleanliness. The gage shall be free of oil, greas
43、e and other organic material. 3.12 Workmanship. The gage shall be uniform in quality and shall be free from irregularities, defects or foreign matter which could adversely affect safety, performance, re1 i ab1 1 i ty or durabi 1 i ty . 4. QUALITY ASSURANCE PROVISIONS 4.1 Responsibility for inspectio
44、n. Unless 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. otherwise specified in the contract or purchase order, the contractor may use his own or any other facilitie
45、s 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 confor
46、m to prescribed requirements. Except as . 8 e o 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-* MIL-G-25520B 66 = 9999906 0474684 MI L-G-25520B(AS) 4.1.1 Responsibility for compliance. All items shall meet all requirements of The absence 0 sectio
47、ns 3 and 5. The inspection set forth in this specification shall become a part of the contractors overall inspection system or quality program. of any inspection requirements in the specification shall not relieve the contractor of the responsi bi 1 i ty of ensuring that al 1 products or supplies su
48、bmitted to the Government for acceptance comply with all requirements of the contract. Sampling inspection, as part of manufacturing operations, is an acceptable practice to ascertain conformance to requirements, however, this does not authorize submission of known defective material, either indicat
49、ed or actual, nor does it commit the Government to accept defective material. 4.2 Cl.assificaion of inspection. The inspection requirements specified herein are classified as follows: a. First article inspection. First article inspection consists of tests and examinations performed on samples which are representative of the production item after award of contract to determine that the production item conforms to the requirements of this specification (see 4.
