1、 INCH-POUND MIL-PRF-24751A(SH) 16 December 2004 SUPERSEDING MIL-F-24751(SH) 1 November 1990 PERFORMANCE SPECIFICATION FANS, VANEAXIAL GAS TURBINE ENCLOSURE COOLING NAVAL SHIPBOARD This specification if approved for use by the Department of the Navy and is available for use by all Departments and Age
2、ncies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers high pressure and HI shock, type TA vaneaxial fans for use in cooling the gas turbine enclosures of ship propulsion/generator systems. 1.2 Classification. Type TA vaneaxial fans are of the following (see 6.2): 1.2.1 Si
3、zes. Sizes PIN Code TA4 1 TA5 2 TA17 3 TA22 4 1.2.2 Current. Current PIN Code 60 Hz a.c. A 1.2.3 Voltage. Voltage PIN Code 3-phase, 440 V, 60 Hz 4 1.2.4 Enclosure. Enclosure PIN Code Spraytight totally enclosed air over W Not applicable N Comments, suggestions, or questions on this document should b
4、e addressed to: Commander, Naval Sea Systems Command, ATTN: SEA 05Q, 1333 Isaac Hull Avenue, SE, Stop 5160, Washington Navy Yard DC 20376-5160 or emailed to commandstandardsnavsea.navy.mil, with the subject line “Document Comment”. Since contact information can change, you may want to verify the cur
5、rency of this address information using the ASSIST Online database at http:/assist.daps.dla.mil. AMSC N/A FSC 4140 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-24751A(SH) 1.2.5 Ambient temperature. Maximum ambient temperature PIN Code 65 C
6、 6 1.2.6 Quiet bearing. Quiet bearing PIN Code Quiet bearing is applied QB 1.2.7 Nonmagnetic. Nonmagnetic PIN Code Nonmagnetic is applied NM 1.3 Part or identifying number (PIN). PINs to be used for standard gas turbine enclosure cooling fan-motor units acquired to this specification are created as
7、follows (see 1.2.1 through 1.2.7): M 24751 - X X X X X XX XX Prefix for Military Specification Specification number Size Current Voltage and phase Enclosure Ambient temp. Quiet bearing Nonmagnetic For example M24751-TA3A4W6QBNM represents a nominal 17,000 cubic feet per minute (ft3/min) vaneaxial fa
8、n driven by a 440 volt (V), 60 hertz (Hz), 3-phase, alternating current (ac), spraytight, 65 C ambient temperature, Navy service A motor, with quiet bearings, and of non-magnetic construction. 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3, 4, o
9、r 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 cautioned that they must meet all sp
10、ecified 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 document to the extent specified
11、herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-S-901 - Shock Tests, HI (High Impact); Shipboard Machinery, Equipment, and Systems Requirement For MIL-B-17931 - Bearings, Ball, Annular, For Qu
12、iet Operation 2 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-24751A(SH) DEPARTMENT OF DEFENSE STANDARDS MIL-STD-167-1 - Mechanical Vibrations of Shipboard Equipment (Type I - Environmental and Type II - Internally Excited) MIL-STD-740-2 -
13、Structureborne Vibratory Acceleration Measurements and Acceptance Criteria of Shipboard Equipment MIL-STD-889 - Dissimilar Metals MIL-STD-1399-300 - Interface Standard for Shipboard Systems, Electric Power, Alternating Current (Metric) MIL-STD-2031 - Fire and Toxicity Test Methods and Qualifications
14、 Procedure for Composite Systems MIL-STD-2142 - Magnetic Silencing Characteristics, Measurement Of (Metric) (Copies of these documents are available online at http:/assist.daps.dla.mil/quicksearch/ or http:/assist.daps.dla.mil or from the Standardization Document Order Desk, 700 Robbins Avenue, Buil
15、ding 4D, Philadelphia, PA 19111-5094.) 2.2.2 Other Government documents, drawings, and publications. The following other Government documents, drawings, and publications form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those c
16、ited in the solicitation or contract. NAVSEA TECHNICAL PUBLICATION S9074-AR-GIB-010/278 - Requirements for Fabrication, Welding and Inspection, Casting Inspection and Repair for Machinery, Piping and Pressure Vessels (Copies of this document are available from the Naval Inventory Control Point, 700
17、Robbins Avenue, Attn: Code 0862 (Cash Sale), Philadelphia, PA 19111, or www.nll.navsup.navy.mil.) 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 documents are those cited in the sol
18、icitation or contract. AIR MOVEMENT AND CONTROL ASSOCIATION, INC. (AMCA) AMCA 99-0401 - Classification for Spark Resistant Construction AMCA 111 - Laboratory Accreditation Program AMCA 210 - Laboratory Methods for Testing Fans for Aerodynamic Performance Rating AMCA 300 - Reverberant Room Method for
19、 Sound Testing of Fans (DoD adopted) (Copies of these documents are available from the Air Movement and Control Association, Inc, 30 West University Drive, Arlington Heights, IL 60004 or online at www.amca.org.) AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI)/AMERICAN BEARING MANUFACTURERS ASSOCIATION
20、(ABMA) ANSI/ABMA STD-4 - Tolerance Definitions and Gaging Practices for Ball and Roller Bearings ANSI/ABMA STD-9 - Load Ratings and Fatigue Life for Ball Bearings ANSI/ABMA STD-13 - Rolling Bearing Vibration and Noise (Methods of Measuring) 3 Provided by IHSNot for ResaleNo reproduction or networkin
21、g permitted without license from IHS-,-,-MIL-PRF-24751A(SH) ANSI/ABMA STD-20 - Radial Bearings of Ball, Cylindrical Roller and Spherical Roller Types Metric Design ANSI/ABMA/ISO 3290 - Rolling Bearings Balls Dimensions and Tolerances (DoD adopted) (Copies of these documents are available from the Am
22、erican Bearing Manufacturers Association, Inc., 1101 Connecticut Avenue, NW, Suite 700, Washington, DC 20036 or online at www.abma-dc.org.) AMERICAN WELDING SOCIETY (AWS) AWS B2.1 - Welding Procedure and Performance Qualification, Standard For AWS B2.2 - Brazing Procedure and Performance Qualificati
23、on, Standard For (Copies of these documents are available from the American Welding Society, 550 NW LeJeune Road, Miami, FL 33216 or online at www.aws.org.) ASTM INTERNATIONAL ASTM B26 - Standard Specification for Aluminum Alloy Sand Castings (DoD adopted) ASTM E119 - Standard Test Methods for Fire
24、Tests of Building Construction and Materials (DoD adopted) ASTM E662 - Standard Test method for Specific Optical Density of Smoke Generated by Solid Materials ASTM E800 - Standard Guide for Measurement of Gases Present or Generated During Fires ASTM F1166 - Standard Practice for Human Engineering De
25、sign for Marine Systems, Equipment and Facilities (DoD adopted) (Copies of these documents are available from ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959 or online at www.astm.org.) INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS (IEEE) IEEE STD 45 - IEEE Recommende
26、d Practice for Electric Installations on Shipboard (DoD adopted) IEEE STD 429 - Standard Test Procedure for the Evaluation of Sealed Insulation Systems for AC Electric Machinery Employing Form Wound Stator Coils (Copies of these documents are available from the Institute of Electrical and Electronic
27、s Engineers, 445 Hoes Lane, P.O. Box 1331, Piscataway, NJ 08855-1331 or online at www.ieee.org.) NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA) NEMA MG 1 - Motors and Generators (DoD adopted) (Copies of this document is available from the National Electrical Manufacturers Association, 1300 Nor
28、th 17thStreet, Suite 1847, Rosslyn, VA 22209 or online at www.nema.org.) 2.4 Order of precedence. In the event of a conflict between 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 an
29、d regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1 First article. When specified (see 6.2), a sample shall be subjected to first article inspection in accordance with 4.2. 4 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-
30、,-MIL-PRF-24751A(SH) 3.2 Materials. Fan shall be of spark resistant construction as defined in AMCA 99-0401 Type B construction. Cast iron shall not be used in the construction of fans nor shall cast iron be used in motors, which are components of fans. Materials shall be corrosion resisting or mate
31、rial shall be protected against corrosion after fabrication. Material degraded during the fabrication process shall be normalized to restore those properties before assembled in any filter. Selected materials shall be capable of meeting all of the operational and environmental requirements specified
32、 herein. 3.2.1 Hazardous material. Materials for use in the construction of fans shall have no effect on the health of personnel when the materials are used for intended purpose. Regardless of other requirements, materials and parts containing asbestos, cadmium, lithium, mercury, or radioactive mate
33、rial shall not be used. 3.2.2 Fasteners. Material for all bolts, nuts, studs, screws and similar fasteners shall be corrosion-resistant passivated or of a material rendered resistant to corrosion. Sheet metal screws shall not be used. Galling shall be prevented. Tapped holes shall be reinforced wher
34、e shearing of thread can occur. 3.2.3 Nonmagnetic construction. When nonmagnetic fan-motor units are specified (see 6.2), all fan parts including the casing, vanes, impeller, impeller bushing, motor mounting, fasteners, washers, conduit box and fittings shall be of nonmagnetic material. Nonmagnetic
35、material is defined as a material, which has a maximum relative permeability of less than 2.0 after fabrication. 3.2.4 Motor material. Motor material shall conform to the requirements of IEEE STD 45 or NEMA MG 1 as applicable for nonmagnetic motors. 3.2.5 Dissimilar metals. Fans and components shall
36、 not be degraded by electrolysis as specified in MIL-STD-889. 3.2.6 Recovered materials. Unless otherwise specified herein, all equipment, material, and articles incorporated in the products covered by this specification shall be new and may be fabricated using materials produced from recovered mate
37、rials to the maximum extent practicable without jeopardizing the intended use. The term “recovered materials” means materials, which have been collected or recovered from solid waste and reprocessed to become a source of raw materials, as opposed to virgin raw materials. None of the above shall be i
38、nterpreted to mean that the use of used or rebuilt products is allowed under this specification unless otherwise expressly stipulated. 3.2.7 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be used to the maximum extent
39、 possible, provided that the material meets or exceeds the operational and maintenance requirements, and promotes economically advantageous life cycle costs. 3.3 Painting. Equipment and component items shall be delivered with the manufacturers standard finish, except as to comply with the requiremen
40、ts of 3.2. 3.4 Welding and allied processes. Surfaces of parts to be welded or brazed shall be free from rust, scale, paint, grease, and other foreign matter. Welding and allied processes shall be performed by personnel certified to AWS B2.1 and B2.2. NAVSEA Technical Publication S9074-AR-GIB-010/27
41、8 shall be used for guidance. 3.5 Identification plates. Each fan shall be provided with a permanently attached corrosion-resistant identification plate. The method of attachment of the identification plate shall be corrosion-resistant. The identification plate shall contain the following informatio
42、n as a minimum: a. Manufacturers name, commercial and government entity, and part number b. Fan identification code c. PIN code d. Direction of airflow and rotation e. Bearing lubrication The identification plate and a duplicate motor identification plate shall be installed on the outside of the fan
43、 casing. 3.6 Interchangeability. In no case shall parts be physically interchangeable or reversible unless such parts are also interchangeable or reversible with regard to function, performance, and strength. 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from
44、 IHS-,-,-MIL-PRF-24751A(SH) 3.7 Operating life. The equipment shall have an operating life of not less than 223,800 hours (equivalent to approximately 30 years of operation). Any part identified as planned replacement parts shall have an operating life, prior to replacement, of approximately 37,300
45、hours (equivalent to approximately 5 years of ship operation). 3.8 Human engineering. The fan shall be arranged so as to achieve safe, reliable, and effective performance by the operator and maintenance personnel and to optimize personnel skill requirements. ASTM F1166 shall be utilized as a guideli
46、ne in applying human engineering design criteria for the fan-motor unit. 3.9 Maintainability. The fan shall be constructed so that: a. Fan impeller shall be mounted on the motor shaft in such a manner that it is removable using commonly available tools. b. Bearings shall be removable using commonly
47、available tools. c. Parts shall be match marked or attached so that reinstallation will be in the same position as originally installed. d. Motor shall be removable using commonly available tools. 3.10 General shipboard design conditions. General shipboard design characteristics shall be as follows:
48、 a. Power source quality - In accordance with MIL-STD-1399-300. 3.11 Fan design requirements. 3.11.1 Aerodynamic design parameters. The quantities of blades and vanes shall be chosen to avoid interacting frequencies within the audible range. The axial distance between blades and vanes shall be chose
49、n with minimum noise amplitude as a prime consideration. Blade tip clearance (radial clearance) shall be the minimum clearance to satisfy 4.5.10. 3.11.2 Configuration. Fans and motors shall operate in any position on shipboard including vertical (with fan impeller either up or down), horizontal (parallel to ships centerline or athwartship), or inclined. Each fan-motor unit shall be a complete assembly. 3.11.3 Sizes. Sizes of gas turbine cooling fans shall be limited
