1、MIL-J-21965D(NAVY) 5 February 1988 SUPERSEDING 30 June 1975 (See 6.5) MIL-W-21965C(NAVY) MILITARY SPECIFICATION WATER COOLING OF SHIPBOARD ELECTRONIC EQUIPMENT GENERAL SPECIFICATION FOR This specification is approved for use within the Department of the Navy, and is available for use by all Departme
2、nts and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers the general design and construction requirements and methods for the internal water cooling of electronic equipment utilizing shipboard cooling water support systems. 1.2 Classification. Heat transfer betwee
3、n heat sources internal to the equipment and the shipboard cooling water shall be of the following methods: a Method 1 - Convection cooling (see 3.2.1). llethod 2 - Conduction cooling (see 3.2.2). Method 3 - Other cooling techniques (see 3.2.3). 2. APPLICABLE DOCUMENTS 2.1 Government documents. 2.1.
4、1 Specifications, standards, and handbooks. The following specifi- cations, standards, and handbooks form a part of this specification to the extent specified herein. Unless otherwise specified, the issues of these documents shall be those listed in the issue of the Department of Defense Index of Sp
5、ecifications and Standards (DoDISS) and supplement thereto, cited in the solicitation. Beneficial comments (recommendations, additions, deletions) and any pertinent data which may be of use in improving this document should be addressed to: Commander, Naval Sea Systems Command, SEA 5523, Department
6、of the Navy, Washington, DC 20362-5101 by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or e by letter. AMSC N/A FSC 4420 DISTRIBUTION STATEMENT A Approved for public release; distribution unlimited THIS DOCUMENT CONTAINS
7、PAGES. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-t , L ” r SPECIFICATIONS MILITARY MIL-B-7883 - Brazing of Steels, Copper, Copper Alloys, Nickel Alloys, Aluminum and Aluminum Alloys. MIL-C-15730 - Cooler, Fluid, Naval Shipboard: Lubricating Oil
8、, Hydraulic Oil, and Fresh Water. MIL-H-24520 - Hose and Hose Assembly for Water Cooling of Electronic Equipment. STANDARDS PI1 L I TARY . MIL-STD-278 - Welding and Casting Standard. DOD-STD-1399, - Interface Standard for Shipboard Systems Cooling Section 532 Water for Support of Electronic Equipnen
9、t. (Metric) HANDBOOK MILITARY MIL-HDBK-251 - Reliability/Design Thermal Application. (Copies of specifications, standards, and handbooks required by contractors in connection with specific acquisition functions should be obtained from.the contracting activity or as directed by the contracting activi
10、ty.) 2.2 Other publications. The following document forms 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 the DoDISS specified in the solicitation. Unless otherwise specif
11、ied, 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. MERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) B 152 - Standard Specification for Copper Sheet, Strip, Plate, and Rolled Bar. (DoD adopted) (App
12、lication for copies should be addressed to the American Society for Testing and Materials, 1916 Race Street, Philadelphia, PA 19103.) (Nongovernment standards and other publications are normally available from the organizations which prepare or which distribute the documents. These documents also ma
13、y be available in or through libraries or other informational services.) 2.3 Order of precedence. In the event of a conflict between the text of this specification and the references cited herein (except for associated detail specifications, specification sheets or MS standards), the text of this sp
14、eci- fication shall take precedence. Nothing in this specification, however, shall supersede 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-,-,-c MIL-W-2LPbSD 4L( m 7777906
15、 0233403 7 W -4 3. REQUIREHENTS 3.1 General. The cooling system of shipboard electronic equipment, or portions therefore, utilizing shipboard cooling water shall conform to the inter- face requirements and constraints established in section 532 of DOD-STD-1399. 3.2 Selection of cooling method. Unles
16、s otherwise specified in the individual equipment specification, method 1, convection cooling, shall be used where all cooling requirements of the equipment can be met. Where unit heat dissipation (watts per square inch) or heat concentration (watts per cubic inch) of a single heat source is beyond
17、the capacity of method 1 cooling, method 2, conduction cooling, shall be used. In cases where a large portion of the total heat dissipation comes from one or a relatively small number of concentrated sources, method 1 cooling may provide general cooling, while method 2 cooling may provide cooling di
18、rectly to the heat sources involved. Where method 1 or 2 cannot provide sufficient cooling, other cooling techniques of method 3 cooling may be used where approved by the Command or agency concerned. The cooling methods to be employed shall be determined in accordance with the guidelines provided in
19、 MIL-HDBK-251. 3.2.1 Method 1, convection cooling. Method 1, convection cooling, shall utilize a self-contained circulating forced air system consisting of the heat - - dissipating parts, air channels, blowers and air-to-water heat exchanger. The blower shall move the air over heat sources and heat
20、exchangers in such direction, quantities, and velocities as to provide maximum protection to heat sensitive parts and to make maximum use of natural convection. 3.2.2 Method 2, conduction cooling. Method 2, conduction cooling shall employ conduction and radiation paths as the major heat transfer med
21、ia from heat sources to water. Materials and mounting methods shall be chosen to provide the lowest practicable thermal resistances from the heat sources to water cooled sinks. Heat dissipating parts shall be mounted on and be thermally bonded to water cooled chassis and panels where feasible. Heat
22、sensitive parts shall be mounted on cooled surfaces and shall have high thermal resistance paths to heat dissipatng parts. Radiant heat exchange among electronic parts shall be minimized by providing thermally grounded reflective shields and surfaces of low heat emissivity. 3.2.3 Method 3, other coo
23、ling techniques. Method 3, other cooling tech- niques such as direct immersion, with free or forced convection, and vaporization cooling either direct or indirect method may be employed where specifically approved by the Command or agency concerned. In the application of these cooling techniques, al
24、l effects of the intimate contact of the coolant and the electronics shall be carefully considered, including the thermal, electrical, chemical, and mechanical aspects. 3.3 Construction. The cooling system construction shall conform to the individual equipment specification, the thermal design guide
25、lines of MIL-HDBK-251 and the requirements specified herein. 3 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3.3.1 Heat flow paths. The heat flow paths from heat sources to the cooling system shall be short, direct, and have as low a thermal resist
26、ance as practicable. Such means shall be consistent with the performance, operating, and maintenance requirements specified in the individual equipment specification and with the adequacy of the electronic and mechanical design. 3.3.2 Water distribution. The distribution of water from the shipboard
27、cooling water system shall be apportioned in accordance with the heat dissipation of each heat exchanger, chassis, or panel served. The water distribution shall be controlled by the cross-sectional area of the water passages as much as possible. Any additional adjustments necessary shall be achieved
28、 with fixed built-in flow devices in the connecting tubing. 3.3.3 Water flow rate. The total water flow rate from the shipboard cooling water system shall be adjusted to be a maximum of 1.4 gallons per minute per kilowatt load, based on a maximum of 2 degrees Celsius (“C) temperature rise in the wat
29、er. 3.3.4 Vater pressure. Except as allowed by section 532 of DOD-STD-1399, the maximum water gauge pressure drop from inlet to outlet of each separately enclosed cabinet of the equipment using shipboard cooling water shall not exceed 10 pounds per square inch (lb/in2) and the portion of the cooling
30、 water system of the equipment using the shipboard cooling water shall withstand a hydro- static gauge pressure test of 150 lb/in2 without evidence of leaks or weeps (see 4.4.4). 3.3.5 Water purity. The cooling system shall operate with the inlet water purity characteristics specified in section 532
31、 of DOD-STD-1399. 3.3.6 Construction and placement of parts. The construction and placement of all parts of the water cooling circuit shall be such that: (a) Minimum chance of leakage exists. (b) Should a leak occur, there is a minimum possibility of water striking electronic parts or electrical cir
32、cuitry. 3.3.7 Enclosures. Enclosures of equipment employing cooling method 1 shall provide for recirculation of internal air and prevent exchange between internal circulating air and the surrounding compartment environmental air. Air channels and baffles shall be provided to develop the local air fl
33、ow rates and velocities necessary to cool all parts. 3.3.8 Water cooled panels. Water cooled panels containing equipment operating controls and indicators shall be constructed and installed so as not to interfere with the requirements for equipment operation or maintenance. 3.3.9 Heat exchanger. Hea
34、t exchangers shall be located so that water from leaks and condensation will not fall on any electronic parts or electrical circuitry. Drains shall be provided at the bottom of enclosure for the removal of this water. Heat exchangers shall be easily removable from the front of the enclosure without
35、removal of or damage to adjacent parts or electrical circuitry. Heat exchangers shall be in accordance with NIL-C-15730. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3.3.10 Piping and fittings. Piping and fittings of the cooling system 1 d shall
36、 be readily accessible for assembly, reassembly and replacement and shall i not be an integral part of supporting structures that provide strength or I rigidity to the equipment. Piping and fittings shall not bear any stresses I I allow for one-handed connect or disconnect operation. other than thos
37、e required to meet the cooling function. Wherever possible, mating piping and fittings shall be terminated or structurally supported to 3.3.10.1 Internal connections. Connections required for channeling the cooling water to various passages within the unit shall be located inside the unit enclosure.
38、 These connections shall be positioned to minimize danger to electronic parts or circuitry within the unit, in case of leaking at the connection and to minimize danger of damage during maintenance. 3.3.10.2 Rigidly mounted chassis and panels. Connections to rigidly r mounted water-cooled chassis and
39、 panels that are not normally movable for maintenance shall be by rigid piping with fixed connections. 3.3.10.3 Hovable chassis, panels, and parts. Connections to movable water-cooled chassis, panels, and parts shall be through a flexible cooling hose assembly. The flexible hose shall be in accordan
40、ce with 3.5.2 and shall be of sufficient length to allow chassis movement to the furthest expected extremity. A stowing mechanism shall be provided to ensure proper stowage. The flexible hose shall connect to rigid tubing attached to fixed members at such locations as to minimize hazard from weeping
41、 at joints. 3.3.11 Vents and drains. Vents and drains shall be provided, as necessary, to allow complete filling, draining, and venting of the cooling system. 3.4 Thermal instrumentation and protection. Thermal instrumentation and protection shall be in accordance with the individual equipment speci
42、fication and the requirements specified herein. 3.4.1 High temperature warning. Warning of abnormal temperature (see 6.3.3) shall be provided by an audible alarm and flashing red light. A switch shall be provided to silence the audible alarm after it has sounded and to cause the red warning light to
43、 maintain visual indication without flashing as long as the abnormal temperature exists. This switch shall not hold the alarm circuit dis- abled during normal operation of the unit. The audible alarm shall not require manual resetting. The red light shall not be extinguished by automatic shut- down
44、of the unit. The location of the alarm, light, and switch shall be as specified in the individual equipment specification. 3.4.1.1 Remote indication To permit monitoring at a remote location, contacts which close when an abnormal temperature is reached shall be provided. These contacts shall be wire
45、d to a connector on the unit or, if stuffing tubes are utilized, to a terminal board in the equipment. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-3.4.2 Emergency cooling. Each unit in which cooling method 1 is employed shall operate at full po
46、wer with the shipboard cooling water supply shut off for a period of at least 8 hours in a 35 + 3C operating environmental tempera- ture without activating the automatic shuthown. This requirement may be met by opening panels or removing portions of the enclosure thereby providing circulation of com
47、partment air in the unit. This procedure shall be of a quick changeover design requiring only the use of screwdriver. 3.4.3 Pressure relief devices. Safety pressure plugs, relief valves, or other devices, shall be provided in each removable water-cooled chassis having quick disconnect fittings, such
48、 that a chassis removed to a workbench and placed in operation will not build up dangerous pressures within the water circuits due to water expansion. Pressure relief devices shall blow out at a maximum gauge pressure of 155 lb/in2. A safety warning plate shall be affixed adjacent to each pressure r
49、elief device. 3.5 Parts, materials, and processes. 3.5.1 Selection. The selection of parts, materials, and processes shall be in acordance with the individual equipment specification and the requirements specified herein. 3.5.2 Hose and hose assembly. The hose and hose assembly shall conform to MIL-H-24520 and shall be not more than 2 years old upon installation or more than 4 years. 3.5.3 Copper,. Flat copper products used in the fabrication of cooling surfaces shall be in accordance w
