1、Beneficial comments (recommendations, additions, deletions) and any pertinentdata which may be of use in improving this document should be addressed to:Commander, SEA 05Q, Naval Sea Systems Command, 2531 Jefferson Davis Hwy,Arlington, VA 22242-5160 by using the Standardization Document ImprovementPr
2、oposal (DD Form 1426) appearing at the end of this document or by letter.AMSC N/A FSC 4140DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited.INCH-POUNDMIL-PRF-19004B25 May 2001SUPERSEDINGMIL-F-19004A18 April 1983PERFORMANCE SPECIFICATIONFANS, CENTRIFUGAL, VENTILATION, N
3、AVAL SHIPBOARDThis specification is approved for use by the Naval Sea Systems Command,Department of the Navy, and is available for use by all Departments andAgencies of the Department of Defense.1.SCOPE1.1 Scope. This specification covers centrifugal fans for use in Navalshipboard heating, ventilati
4、ng, and air conditioning systems.1.2 Classification. Fans covered by this specification are of the followingtypes, as specified (see 6.1).Type CC - Centrifugal, motor driven (high-impact - shock)Type X-CC - Centrifugal, motor driven (non-Shock, commercial motor)2.APPLICABLE DOCUMENTS2.1 General. The
5、 documents listed in this section are specified in Sections3 and 4 of this specification. This section does not include documents citedin other sections of this specification or recommended for additionalinformation or as examples. While every effort has been made to ensure thecompleteness of this l
6、ist, document users are cautioned that they must meetall specified requirements documents cited in sections 3 and 4 of thisspecification, whether or not they are listed.2.2 Government documents.2.2.1 Specifications, standards. The following specifications, standards,publications and handbooks form a
7、 part of this document to the extentspecified herein. Unless otherwise specified, the issues of these documentsare be those listed in the issue of the Department of Defense Index ofSpecifications and Standards (DODISS) and supplement thereto, cited in thesolicitation (see 6.2).SPECIFICATIONSDEPARTME
8、NT OF DEFENSEMIL-S-901 Shock Tests, H.I. (High-Impact); ShipboardMachinery, Equipment and Systems, RequirementsforMIL-B-17931 Bearings, Ball, Annular, for Quiet OperationProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-19004B2STANDARDSDEPARTME
9、NT OF DEFENSEMIL-STD-167-1 Mechanical Vibrations of Shipboard Equipment(Type I - Environmental and Type II - Internallyexcited)MIL-STD-1399 Interface Standard for Shipboard Systems, Sect300, Electric Power, Alternating CurrentMIL-STD-2031 Fire otherwise, it shall be shock tested on thelight weight m
10、achine as specified for grade A shock of MIL-S-901. Shock testacceptance shall not be contingent upon the ability of the equipment tosatisfy noise and vibration requirements. Evidence of fragmentation orProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,
11、-MIL-PRF-19004B12missile effect of parts, deformation that will cause active interferencebetween parts, or failure to operate shall be cause for rejection. Resilientmounting shall not be used unless specified (see 6.2). Fan-motor units thathave passed this test may be used as production units after
12、replacement ofmotor bearings.4.7.1.1 Shock on lightweight machine. The motor and fan support shall bemounted as shown on Figure 4c of MIL-S-901. The test shall consist of nineblows with the unit operating at maximum speed and nine blows with the unitnot engaged.4.7.1.2 Shock on medium weight machine
13、. The test of a fan-motor unit shallconsist of nine blows indicated in Table VI. The required mountings forrequired tests in Table VI are as follows: (Designations for rotation anddischarge of centrifugal fans are in accordance with AMCA 2406-66).1. CWTH or CCTH, motor and impeller shaft horizontal.
14、2A. CWTH or CCTH, motor and impeller shaft horizontal, mounting baseinclined 30.2B. CWUB or CCOB, base, motor and impeller shaft inclined 30, motor ontop.TABLE VI. Test on medium weight shock machine.BlowNo.GroupNo.HAMMERdropAnviltravel (in)OperatingConditionFanOrientation123456789IIIIIIIIIIIIIIIIII
15、(Based onweight, seeMIL-S-901)331.5331.5331.5SecuredOperatingSecuredOperatingSecuredOperatingSecuredOperatingSecuredNo. 1No. 1No. 1No. 2ANo. 2ANo. 2ANo. 2BNo. 2BNo. 2BUpon completion of the shock test, post-shock test inspection, and testsspecified in Table V, the fan-motor unit shall be returned to
16、 the contractorfor examination and further testing.4.7.2 Vibration test. Fan-motor units shall be subjected to type Ienvironmental vibration tests as specified in MIL-STD-167-1. The exploratoryvibration test specified in MIL-STD-167-1 shall include frequencies up to 33Hz at the table amplitude speci
17、fied herein. The vibration test shall beconducted as specified in 4.11. Any unit that fails to meet any requirementshall be rejected.4.7.3 Balance test. In this test, the fan-motor unit shall be operated atmaximum speed and free delivery, with shaft horizontal. It shall be suspendedfrom a stand by m
18、eans of two elastic vibration cords, one secured to each endflange. The cords shall have a natural frequency of less than 1/4 of theminimum rotational frequency of the unit in Hz. The static deflection shall bewithin the limits of MIL-STD-167-1 for elastic mounting elements, and thisshall be the bas
19、is for determining cord size for each unit tested. As analternative to the suspension test, the fan-motor unit shall be suspended froman electric hoist by means of two chains, one secured to the end flanges ofthe fan-motor unit (that is, the ends of the chain secured to oppositeflanges); one secured
20、 to the electric hoist and to the center of the chainsecured to the end flanges. The length of the chains shall be not less than 15inches nor greater than 35 inches, and the link size of the chains shall benot less than 1/4 inch nor greater than 3/8 inch. With either method, theinternally excited vi
21、brational displacement (single amplitude mils, peak)shall be measured as follows: four axial measurements 90 degree apart on theface of each end flange, one horizontal measurement perpendicular to the axisProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,
22、-,-MIL-PRF-19004B13on the edge of each flange, and one vertical measurement on the top edge ofeach flange. The maximum amplitude of vibration shall be the maximum singlereading and not an average. The operating frequency at which the maximumamplitude occurs shall be measured. Exceeding vibration lim
23、its specified in3.9.2 is cause for rejection.4.7.4 Performance. Performance tests shall be conducted in accordance withAMCA 210. Any of the alternate test stands and associated instrumentation maybe used. The total pressure or the volume or both not being within thespecified limits is cause for reje
24、ction.4.7.4.1 Stall and recovery. Tests shall be conducted in accordance with AMCA210.4.7.5 Airborne noise. Octave band sound power levels for a fan-motor unitshall consist of the measurement of sound pressure levels and the computationof sound power levels in accordance with procedures and instrume
25、ntationrequirements defined in AMCA 300-96, and amendments to those procedures asidentified herein. The fan-motor unit shall be operated at the design pointduring airborne noise testing, see 3.17.1. Dual speed fans shall be operatedat high speed during noise tests. All sound measuring instrumentatio
26、n shallbe laboratory calibrated within one year of the date of test, excluding thereference sound source which shall comply with the laboratory calibrationrequirements stated in AMCA 300-96. A random incidence response microphoneand a type I (precision) sound level meter conforming to the requiremen
27、ts ofAMCA 300-96 shall be used. The minimum distance between the extreme points ofthe microphone swing as described in AMCA 300-96 shall be 27 ft., and thespeed of traverse of the microphone shall not exceed 2.4 ft./sec. Soundpressure readings shall be a time-weighted average over an integral number
28、(one or more) of microphone swings. Sound pressure level readings shall beaveraged over a minimum period of observation of 30 sec. Resilient mountsshall be loaded within the design load range for the type of mount selected.The frequencies of the natural modes of vibration of the mounted fan in theve
29、rtical direction shall not exceed 11 Hz or one-fourth of the lowest forcingfrequency of the fan, whichever is lower. When a duct section is attached toa fan-motor unit to facilitate measurements, it shall have the same interior,open cross sectional dimensions as that of the fan-motor unit to which i
30、t isattached. There shall be no exposed sound absorbing material on the interioror exterior surfaces of the attached ducts. No sound attenuating devicesshall be installed within attached ducts. An orifice plate shall beinstalled if necessary to obtain design pressure at a known operating point.If an
31、 orifice plate is installed, it shall be a quiet type that does notproduce excessive flow-induced noise.4.7.5.1 Total sound power. Test procedures and calculation procedures todetermine total sound power levels for a fan-motor unit shall be in accordancewith Appendix H of AMCA 300-96, installation t
32、ype B: free inlet/ducted outlet,and Figure 4 of AMCA 300-96. The fan-motor unit and attached discharge ductwith orifice plate shall be placed entirely within the reverberant test room.4.7.5.2 Inlet sound power. Test procedures and calculation procedures todetermine inlet sound power levels for a fan
33、-motor unit shall be in accordancewith Figure 2 of AMCA 300-96, installation type D: ducted inlet/ducted outlet.No orifice plate shall be installed in the inlet duct. The fan-motor unit andattached discharge duct with orifice plate shall be placed entirely within thechamber, and sound pressure level
34、 measurements shall be made within thereverberant test room. Acoustical treatments shall be placed within thechamber to provide an acoustic seal at the penetration in the wall separatingthe chamber from the reverberant room as necessary to ensure that no noisecontributions are transmitted from the c
35、hamber into the reverberant test room.4.7.5.3 Outlet sound power. Test procedures and calculation procedures todetermine outlet sound power levels for a fan-motor unit shall be inaccordance with Figure 3 of AMCA 300-96, installation type B: freeinlet/ducted outlet. An orifice plate shall be installe
36、d within the dischargeProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-19004B14duct if necessary to obtain fan-motor unit operation at the design point. Thefan-motor unit with attached discharge duct shall be placed within thechamber. A sectio
37、n of the discharge duct, approximately 2 to 3 duct diameterslong and housing an orifice plate, shall extend into the reverberant testroom, and sound pressure level measurements shall be made within the reverb-erant test room. Acoustical treatments shall be placed within the chamber asnecessary to pr
38、ovide an acoustic seal at the penetration in the wallseparating the chamber from the reverberant room, and to ensure that no noisecontributions are transmitted from the chamber into the reverberant test room.4.7.5.4 Casing sound power. Test procedures and calculation procedures todetermine sound pow
39、er levels radiated from the casing of a fan-motor unitshall be in accordance with Appendix G of AMCA 300-96. Duct sections attachedto a fan-motor unit to facilitate testing to determine casing radiated soundpower shall be rigid, heavy gauge metal ducts and/or solid, double wall ductsto eliminate noi
40、se contributions transmitted through duct walls. The noisetransmission loss of the walls of the reverberant test room shall be such thatnoise transmitted into the reverberant test room from adjacent spaces does notcontribute to the sound power levels of the fan-motor unit. Penetrations inthe walls o
41、f the reverberant room in way of ducts shall be acoustically sealedto prevent noise contributions from being transmitted into the reverberanttest room from the adjacent room.4.7.5.5 Airborne noise detected by ear. Fan-motor units not undergoingairborne noise testing described in 4.7.5.1 through 4.7.
42、5.4 shall be operatedat their design points. Any unusual airborne noise or any airborne noisethought to be excessive shall be corrected if the cause is apparent. If thecause is not apparent and the condition is not corrected, the fan-motor unitshall be tested in accordance with 4.7.5.1, and sound po
43、wer levels shall becomputed to determine conformance with sound power level requirementsspecified in Table IV.4.7.5.6 Airborne noise test facility. The facility wherein measurements offan-motor unit airborne noise are performed shall be registered in accordancewith AMCA 111 as being a qualified faci
44、lity in which to perform octave bandsound measurements in accordance with AMCA 300-96.4.7.6 Motor temperature. Motor temperature rise shall be measured asspecified in the applicable motor specification. In each test, the motorshall be installed on the fan, and a duct shall be attached to the dischar
45、ge.Maximum load shall be obtained by means of terminal throttle on the test duct.Since neither the fan nor a test stand will normally be available at the motorplant, the test may be conducted at the plant of the contractor. Motors witha temperature rise of any part in excess of specification limits
46、or bearingsin excess of 3.16.5 shall be rejected.4.7.7 Explosion. This test is applicable only to electrical equipmentrequiring an explosion-proof enclosure. Test shall be performed in apetroleum ether atmosphere and certified by a nationally recognizedlaboratory. Test shall include the conduit and
47、conduit box actually used withthe fan. Prior to the explosion test, the air leakage rate of the motorenclosure shall be determined by pressurizing the interior of the motorenclosure to 10 pounds per square inch (lb/in2) and measuring the period oftime in seconds for the pressure to drop from 10 to 4
48、 lb/in2. The air leakagerate shall be recorded on the applicable motor drawing.4.7.7.1 Air leakage rate. The motor of explosion-proof fan-motor units shallhave motor enclosure air leakage rate measured to determine whether the rateof leakage exceeds that determined in 4.7.7. Any explosion-proof moto
49、r wherethere is evidence that the predetermined rate of leakage is exceeded whenmeasured shall not be offered for delivery.4.7.8 Casing tightness. The casing tightness test shall be conducted asfollows:Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-PRF-19004B15a.Blank flanges (one with air supply and gauge connections) shall bebolted to gasketed fan flanges.b.Air at a pressure 50 percent higher than the maximum pressurecapability of
