1、 AMSC N/A FSC 2935 INCH-POUND MIL-PRF-25478D 06 May 2013 SUPERSEDING MIL-PRF-25478C 29 December 1997 PERFORMANCE SPECIFICATION COOLERS, LUBRICATING OIL, AIRCRAFT, GENERAL SPECIFICATION FOR This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1
2、.1 Scope. This is general specification for aircraft engine lubricating oil coolers that provide oil temperature regulation for aircraft gas turbine engines using high temperature synthetic base lubricating oil, and aircraft piston engines, turbo propeller gear boxes, and helicopter transmission gea
3、r boxes using petroleum based oil. 1.2 Classification. Lubricating oil coolers (oil coolers) will be of the following types as specified in the acquisition document (see 6.2). 1.2.1 Type. The type of oil coolers are as follows: Type IA - Petroleum base lubricating oil cooler for aircraft piston engi
4、nes and turbo propeller gear boxes Type IB - Petroleum base lubricating oil cooler for helicopters transmission gear boxes. Type II - Synthetic base lubricating oil cooler for aircraft gas turbine engines. Comments, suggestions, or questions on this document should be addressed to Oklahoma City Air
5、Logistics Center/ENSDDA, 3001 Staff Drive, Tinker AFB, OK 73145 or emailed to tinker.dsptinker.af.mil. Since contact information can change, you may want to verify the currency of this address information using the ASSIST Online database at https:/assist.dla.mil . Provided by IHSNot for ResaleNo rep
6、roduction or networking permitted without license from IHS-,-,-MIL-PRF-25478D 2 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3, 4 or 5 of this specification. This section does not include documents cited in other sections of this specification o
7、r recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of the documents cited in sections 3, 4, or 5 of this specification, whether or not they are
8、listed. 2.2 Government documents. 2.2.1 Specifications and standards. The following specifications and standards form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. DEPARTMENT OF DEFEN
9、SE SPECIFICATIONS MIL-PRF-5636 - Valve, Lubricating Oil Cooler, Temperature Regulating With Surge Protection General Specification For DEPARTMENT OF DEFENSE STANDARDS MS33786 - Fitting Installation, Flared Tube and Hose, Swivel (Copies of these documents are available online at https:/assist.dla.mil
10、/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 the extent specified herein. Unless otherwise specified, the issues of these document
11、s are those cited in the solicitation or contract. AMERICAN SOCIETY FOR QUALITY (ASQ) ANSI/ASQ-Z1.4 - Sampling Procedures and Tables for Inspection by Attributes (ASQ documents may be obtained at http:/asq.org or addressed to the American Society for Quality, P.O. Box 3005, Milwaukee, WI 53201-3005
12、or 600 North Plankinton Avenue Milwaukee, Wisconsin, 53203, USA) Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-25478D 3 AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) ASTM B117 - Salt Spray (Fog) Apparatus, Operating (ASTM documents may
13、be obtained at http:/www.astm.org/ or addressed to the American Society for Testing and Materials, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959.) AEROSPACE INDUSTRIES ASSOCIATION of AMERICA, INC. (AIA) NASM33588 - Nut, Self-Locking, Aircraft, Reliability And Maintainability Usage Requirem
14、ents For (AIA/NAS documents may be obtained at www.aia-aerospace.org/ or from Aerospace Industries Association, 1000 Wilson Boulevard, Suite 1700, Arlington, VA 22209-3928.) 2.4 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between the text of this
15、 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 Associated specification sheets. The individual item requirements sh
16、all be as specified herein and in accordance with the applicable specification sheet cited in the acquisition document (see 6.2). In the event of any conflict between the requirements of this specification and the acquisition document, the latter shall govern. 3.2 First article. When specified (see
17、6.2), a sample shall be subjected to first article inspection in accordance with 4.2. 3.3 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be used to the maximum extent possible, provided that the material meets or exce
18、eds the operational and maintenance requirements, and promotes economically advantageous life cycle costs. 3.4 Workmanship. The oil cooler, including all parts and equipment, shall be constructed in accordance with commonly accepted industrial workmanship standards. 3.5 Materials. All materials shal
19、l be corrosion resistant or suitably treated to resist corrosion due to electrolytic decomposition from hydraulic fluids, fuels, fungus, salt fog, and any other condition that may be encountered during operational use or storage. The use of toxic chemicals, hazardous substances, or ozone depleting c
20、hemicals shall be avoided, whenever feasible. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-25478D 4 3.5.1 Compatibility. All materials shall be compatible with the lubricating oil and preservative compounds specified in the acquisition doc
21、ument (see 6.2). No copper or magnesium shall be used. 3.6 Component parts. Unless otherwise specified in the acquisition document (see 6.2), the oil cooler shall consist of the core assembly, oil inlet and outlet ports, a drain device, a temperature control device, a surge protection device, and a
22、bypass warm-up passage. The temperature control device, a surge protection device, and a bypass warm-up passage can be combined into one device as described in MIL-PRF-5636. 3.6.1 Castings. f metal is chosen and a casting process is used, then the casting shall be clean, free from blow-holes, porosi
23、ty, cracks, and other defects. 3.6.2 Temperature control device. The oil cooler shall incorporate a temperature control device which, in conjunction with a bypass warm-up passage, controls the temperature of the oil at the oil cooler outlet to the value specified in the acquisition document (see 6.2
24、). The temperature control device shall be a removable part of the oil cooler assembly. 3.6.3 Surge protection device. The surge protection device shall be used on the bypass warm-up passage outlet and shall be a removable part of the oil cooler assembly. The surge protection device shall open at th
25、e minimum differential pressure relief setting and shall limit the maximum differential pressure as specified in the acquisition document (see 6.2). 3.7 Interfaces. 3.7.1 Fittings. The oil inlet and outlet ports shall permit connection of fittings conforming to MS33786. 3.7.2 Dimensions and weight.
26、The overall dimensions and weight shall be as specified in the acquisition document (see 6.2). 3.7.3 Locking thread parts. Threaded parts shall be secured to prevent loss during operation. Self-locking nuts, shall be in accordance with NASM33588. Staking and the use of lockwashers shall not be permi
27、tted. 3.8 Performance. 3.8.1 Static pressure. There shall be no leakage or permanent distortion of the oil cooler when subjected to hydrostatic pressure as specified in the acquisition document (see 6.2). 3.8.2 Bypass warm-up passage pressure drop without air flow. Unless otherwise specified in the
28、acquisition document (see 6.2), the oil pressure drop through the bypass warm-up passage shall not exceed 8 psi. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-25478D 5 3.8.3 Pressure drop with air flow. The pressure drop across the oil cool
29、er shall not exceed 30 psi for Type IA and Type IB oil coolers with temperature regulation; 25 psi for Type IA and Type IB oil coolers without temperature regulation; and 20 psi, unless otherwise specified in the acquisition document (see 6.2), for Type II oil coolers with or without temperature reg
30、ulation. 3.8.4 Pressure drop without air flow. The pressure drop across the oil cooler with no air flow shall not exceed the maximum allowable pressure for the engine oil scavenging pump system as specified in the acquisition document (see 6.2). 3.8.5 Pressure resistance. The oil cooler shall withst
31、and an oil pressure drop of 80 psi with an oil temperature of less than 100oF and the bypass warm-up passage closed. 3.8.6 Pressure cycles. The oil cooler shall withstand 50,000 air pressure cycles applied to the oil inlet with the oil outlet closed. An air pressure cycle is from 3 +3 psi to 60 +1 p
32、si and back to 3 +3 psi in 4.5 +0.5 seconds. 3.8.7 Ratings. 3.8.7.1 Rated oil flow. Rated oil flow shall meet the requirement specified in the acquisition document (see 6.2). 3.8.7.2 Rated air flow. Rated air flow shall meet requirement specified in the acquisition document (see 6.2). 3.8.7.3 Oil he
33、at rejection. At rated oil flow, rated air flow, and the air inlet temperature specified in the acquisition document (see 6.2), the total heat rejection (British Thermal Units per minute) from the oil cooler shall be equal to or greater than total heat rejection specified in the acquisition document
34、 (see 6.2). 3.8.8 Direction of air flow. Unless otherwise specified (see 6.2), the oil cooler shall meet performance requirements with the air flow in either direction. 3.9 Environmental conditions. 3.9.1 Fluid resistance. The oil cooler shall withstand oil temperatures of -65oto 350oF without leaka
35、ge or permanent distortion. 3.9.2 Vibration. There shall be no leakage or permanent distortion of the oil cooler when subjected to vibration. The vibration shall be maintained at an amplitude such that an acceleration of 10g is imposed upon the oil cooler. 3.10 Maintainability. A drain device shall
36、be provided on the oil cooler which shall permit complete drainage of the oil cooler when installed in the aircraft. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-25478D 6 3.11 Identification. The oil cooler shall be permanently and legibly
37、 marked with the following (see 6.2). a. Nomenclature b. Serial number c. National stock number d. Contract number e. Manufacturers CAGE code f. Manufacturers part number g. Date of manufacture 3.11.1 Synthetic rubber parts. If used, synthetic rubber parts, except parts without suitable surface area
38、, shall be marked with the cure date. 3.12 Interchangeability. All parts having the same manufacturers part number shall be functionally and dimensionally interchangeable. 3.13 Cleaning. The oil cooler shall be free of acids, alkaloids, halides, or other foreign materials. 4. VERIFICATION 4.1 Classi
39、fication of inspections. The inspection requirements specified herein are classified as follows: a. First article inspection (see 4.2). b. Conformance inspection (see 4.3). 4.2 First article inspection. When required (see 6.2), first article inspection shall be performed on two complete oil coolers
40、and shall include the tests indicated in 4.6. 4.3 Conformance inspection. Conformance inspection shall include the tests indicated in 4.3.1 and 4.3.2. 4.3.1 Individual tests. Each oil cooler shall be subjected to the following tests: a. Examination of product (see 4.6.1) b. Cleaning (see 4.6.2) c. S
41、tatic pressure test (see 4.6.3) 4.3.2 Sampling tests. A sample of oil coolers shall be selected in accordance with ASQC-Z1.4, and shall be subjected to the following tests at the inspection level (normal, tightened, or reduced) specified in the acquisition document (see 6.2). (In the oil pressure dr
42、op without air flow test, only one measurement, with oil at a temperature of 145o+2oF, shall be made): Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-25478D 7 a. Pressure drop without air flow (see 4.6.5). b. Pressure cycles (see 4.6.8 and 6
43、.4) 4.4 Test conditions. Unless otherwise specified (see 6.2), all inspections shall be performed in accordance with the following test conditions. 4.4.1 Ducting. The cooling air inlet and outlet ducts on the test bench shall be equivalent in size and shape to that of the aircraft installation on wh
44、ich the oil cooler is to be used. Dimensions shall be as specified in the acquisition document (see 6.2). 4.4.2 Oil. The oil used for all tests shall be specified in the acquisition document (see 6.2). 4.4.3 Tolerances. Unless otherwise specified, the variables specified at fixed values are permitte
45、d to deviate from specified conditions: +2oF for all temperatures, +2% for rated oil flow, and +2% of rated air flow for any air flow. The calculated heat added to the air (air temperature rise x air flow x specific heat of air) shall be within 5% of calculated heat transferred from the oil (oil tem
46、perature drop x oil flow x specific heat of oil). Heat balance discrepancies of more than 5%, for all heat rejection runs other than Oil pressure drop with air flow are unacceptable. 4.5 Requirements cross-reference matrix. Table I provides a cross-reference matrix of the section 3 requirement teste
47、d or verified in paragraphs below. TABLE I. Requirements cross-reference matrix Requirement Verification Requirement Verification 3.2 4.2 3.8.4 4.6.5 3.4 4.6.1 3.8.5 4.6.6 3.5 4.6.1, 4.6.11 3.8.6 4.6.8 3.5.1 4.6.1, 4.6.9 3.8.7.1 4.6.4, 4.6.5 3.6 4.6.1 3.8.7.2 4.6.4 3.6.1 4.6.1 3.8.7.3 4.6.4 3.6.2 4.
48、6.1, 4.6.4, 4.6.5, 4.6.10 3.8.8 4.6.4 3.6.3 4.6.1, 4.6.4, 4.6.5, 4.6.10 3.9.1 4.6.9 3.7.1 4.6.1 3.9.2 4.6.7 3.7.2 4.6.1 3.10 4.6.1 3.7.3 4.6.1 3.11 4.6.1 3.8.1 4.6.3 3.11.1 4.6.1 3.8.2 4.6.5 3.13 4.6.1, 4.6.2 3.8.3 4.6.4 Provided by IHSNot for ResaleNo reproduction or networking permitted without li
49、cense from IHS-,-,-MIL-PRF-25478D 8 4.6 Tests. 4.6.1 Examination of product. The oil cooler shall be examined for compliance with requirements for materials, weight, identification, compatibility, components, castings, temperature control and surge protection devices, fittings locking threaded parts, maintainability, dimensions, workmanship, and presence of for
