1、- tIIL-V-lbA3A 43 7777906 0273441 7 r 15 November 1971 SUPERSEDING MIL-V-I8683(SHIPS) 20 July 1955 (See 6.5) MILITARY SPECIFICATION VACUUM PUMPS, POWER DRIVEN, CENTFUFUGAZ, PUMP PRIMING SERVICE, NAVAZ, SHIPBOARD 1. SCOPE 1.1 This specification covers the design and construction of vacuum pumps for t
2、he purpose of priming cen- trifugal pumps by removing air and associated vapors from pump casings and suction piping. 2. APPLICABLE DOCUMENTS 2.1 # The following documents of the issue in effect on date of invitation for bids or request for proposal, form a part of the specification to the extent sp
3、ecified herein. SPECIFICATIONS FH)ERAz, FF-EI71 - Bearing, Ball, Annular, (General Purpose). QQ-12-390 - Copper Alloy Castings (Including Cast Bar). QQ-N-281 - Nickel-Copper-Alloy Bar, Plate, Rod, Sheet, Strip, Wire, Forgings, and.Structura1 and QQ-N-288 - Nickel-Copper Alloy and Nickel-Copper-Silic
4、on Alloy Castings. TT-P-645 - Primer, Paint, Zinc-Chromate, plwd Type. GGG-P-781 - Puller, Mechanical Puller Attachment, Mechanical, and hiller Set, Mechanical. MGE857 - Bolts, Nuts, and Studs. Mn-S-901 - Shock Tests, H.I. (High-Impact); Shipboard Machinery, Equipment and Systems, Require- ments For
5、. ML-E-1000 - Drawings, Jhgineering and Associated Lists. MIL-l?-1000/2 - Drawings, Engineering and Associated Lists. MIL-C-2212 - Controllers, Electric Motor, A.C. or D.C. and Associated Switching Devices, Naval MIL-P-15024 - Plates, Tags and Bands for Identification of Equipment. MIL-P-15024/5 - P
6、lates, Identification. - MIL-M-15071 - Manuals, Technical: MIGEL15CO - Enamel, Equipment, Light-Gray (Formula No. 11). MIL-P-15137 - Provisioni MIL-P-15328 - Primer (Wash), Pretreatment, Blue (Formula No. 117-B for Metals). MIL-P-16789 - Preservation, Packaging,: Packing and Marking of Mps General,
7、and Associated MIL-M-17059 - Motors, 60 Cycle, Alternating Current, Fractional H.P. (Shipboard Use). MIL-M-17060 - Motors, 60 Cycle, Alternating Current, Integral Horsepower (Shipboard Use). MIL-M-17413 - Motors, Direct-Current, Integral H.P. (Shipboard Use). MIL-P-17545 - Primer Coating, Alkyd-Red
8、Lead Type, Formula No, 116 and Formula No. 116D. MIL.-M-17556 Motor, Direct-Current, Fractional H.P. (Shipboard Use). MIL-M-38761 - Microflming and Photographing of Engineeri the performance is equal to or better than that of the centrifugal displacement wet vacuum type; and the weight, space, and p
9、ower requirements do not exceed those of the centrifugal displacement wet vacuum type. 3.3.3 Mounting. 3.3.3.1 Pump units shall be horizontally mounted. 3.3.3.2 When specified (see 6.), the pump unit shall be mounted on a bedplate which also serves as reser- Special attention shall be given to the d
10、esign of close-coupled pump to insure that leakage from voir for the seal water. 3.3.3.3 the pump stuffing box glands cannot enter motor frames or bearing brackets. 3.3.4 Bearinas. 3.3.4.1 Radial and thrust bearings shall be of the ball type. 3 Provided by IHSNot for ResaleNo reproduction or network
11、ing permitted without license from IHS-,-,-3.3.4.2 The use of ball bearings shall be subject to the speed limitations of FF-B-171 except where prior 3.3.4.3 Installation. 3.3.4.3.1 approval of the commsnd or agency concerned has been granted. Bearings shall be installed in housings separate from and
12、 independent of the stuffing boxes and with adequate protection from gland leakage. around the shaft. 3.3.4.4 Lubrication of the ball bearings shall be in accordance with FT-B-171. Suitable means shall be provided to prevent escape of lubricant All baffles, wipers, and related parts shall be readily
13、 renewable. 3.3.5 Motors. 3.3.5.1 Al1 motors for driving pumps shall be of the types and characteristics specified (see 6.1), and shall conform to MILM-17413 or MIL-M-17556 for direct current (d.c.) motors, or MIL-M-17059 or MIL-M-17060 for alternating current (a.c.) motors. 3.3.5.2 The horsepower r
14、ating of each motor shall be not less than the rmibum brake horsepower of the driven pump under any condition from shut-off to free delivery. The actual motor rating shall be in accordance with Navy standard motor ratings. a possibility of an unpredictably high frictional load due to improper adjust
15、ment of the gland or to some other cause, then the mxhm brake horsepower shall be multiplied by a safety factor 1.5 - (ma. Bwl before select- If the maximum brake horsepower of the pump is less than 2, and if there is ing the next larger Navy standard rating. 4 I. 3.3.6 Controllers. All motor contro
16、llers shall be of the characteristics specified (see 6.1) and shall conform to MIL-2-2212 for both a.c. and d.c. controllers. # 3.3.7 Shockproofness. 3.3.7.1 The design of all complete pumping units shall be such that they are capable of passin the grade A, hull mounted, class I, medium weight, type
17、 A shock ruirements specified in MIL-S-901 (see 4.4.7y. application is given. of the usual methods of anal ical mechanics. strength (0.2 percent offsetyof the material. Normal stresses in parts, such as the tensile stress in a bolt due to initial pull-up It is of paramount importance that the max- h
18、um accelerations possible under the shock tests be utilized in the design of holding down bolts, supporting feet or lugs, and main structural members of the equipment, and that no failure or permanent deformtion occur as a result of-shocks. accelerations than the values for whioh the whole assembly
19、is designed unless the designer has reason to believe that higher accelerations will be experienced by the parts. Hole diameters shall be no more than 1/32 inch larger than the bolts for sizes up to and including 3/4 inch, and no more than 1/16 inch larger than bolts of 3/4 inch size. 3.3.7.2 Shockm
20、ounts shall not be used unless command or agency approval of the mount and its proposed 3.3.7.3 The determination of stresses resulting from the shock tests is accomplished by the application The allowable stress in parts due to shock shall be the yield shall not be added to the shock stresses. Part
21、s of an assembly mounted on a comon rigid base need not be designed for higher 3.3.7.4 Bolts designed to be stressed in shear shall be installed in holes with a minimum of clearance. 3.3.8 Painting. 3.3.8.1 For pumps operating at a temperature of 3009. or less, all external unmachined surfaces of un
22、gal- vanized ferrous metal parts shall be thoroughly cleaned and coated with one coat of pretreatment, in accordance with MIL-P-15328, and one coat of zinc chromate primer in accordance with TT-P-645, or one coat of red lead primer in accordance with MIGP-17545, followed by a finish coat of light gr
23、ay equipment enamel with MIL-E-15090. 3.3.8.2 Painting of external aurfaces of nonferrous parts of pumps will not be required. 3.3.9 Threaded parts such as bolts, studs and nuts shall conform to MIL-B-857 and Handbook H28. 3.3.10 Welding shall be in accordance with MIL-STD-278 except for the welding
24、 of the seal tank. 3.4 Detaif rwuirements. 3.4.1 Casings. 3.4.1.1 in accordance # The casings of all pumps shall be designed giving msrrdmum consideration for accessibility and ease of replacement of pacldng, mechanical seals, bearings, end wearable parts such as rotors. # I Provided by IHSNot for R
25、esaleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-I8683A( SHIPS) 3.4.1.2 Sufficient clearance shall be provided around bolt heads and nuts to permit the use of ordinary tools. in re-assembly. 3.4.1.3 Fitted bolts or dowel pins shall be provided to insure maintenance of
26、alignment of casing parts 3.4.1.4 Casings shall be provided with drain connections. 3.4.2 Suction and discharge connections. 3.4.2.1 Suction and discharge connections shall be flanged for mating with flanges in accordance with MIL- STD-438 or MIL-STD-777 as applicable, and as specified (see 6.1), ex
27、cept tapered pipe threads are acceptable for use in grease fittings. # 3.4.2.2 The thickness of the flanges shall be not less than that specified in the applicable specification or drawing. 3.4.3 Rotors and shafts. 3.4.3.1 Rotor surfaces shall be smooth finished. 3.4.3.2 Rotors shall be keyed on the
28、 shaft and secmely held against lateral movement by locked nuts or other means approved by the command or agency concerned. 3.4.3.3 Shaft threading shall be countel. to the direction of rotation except where both right hand and left hand units of the same design are involved, in whioh case, in order
29、 to reduce the number of shafts required for repair parte, the threading shall be right hand for all units and the threaded parts shall be locked in place. 3.4.3.4 Shafts shall be fitted with shaft sleeves in way of stuffing boxes unless otherwise approved by # the command or agency concerned. 3.4.3
30、.5 The shafts of all pumps, except those driven by a.c. motors, shall be provided with means to per- mit the ready and direct use of portable tachometers. 3.4.4 Stuffing boxes and packing. 3.4.4.1 Stuffing boxes shall be of adequate depth and design to reduce leakage to a minimum under all operating
31、 conditions. Mechanical seals are acceptable. Packing shall be in accordance with Drawing E?-153. 3.4.4.2 AL1 packing shall be of a brand approved by the command or agency concerned. 3.4.4.3 The design shall be such as to insure that leakage from the glands cannot reach the bearings or be thrown ove
32、r bearing housings or driving units. out internally and the shafts provided with flingers. provided. for setting up. This shall preferably be accomplished by using glands cored Ample drip pockets, spray shields and drains shall be 3.4.4.4 Glands shall be split in halves with the halves secured toget
33、her in a manner to form solid rings 3.4.4.5 Ail stuffing box glands shall be set up by units threaded on gland swing bolts, or on studs secured in the casings. Mechanical seals shall not be positioned by use of set screws. pressure is supplied to the seal faces under all conditions of operation and
34、that there is adequate circulation of the liquid to the seal faces to minimize the deposit of foreign matter on the seal parts. 3.4.4.6 Mechanical sea;ls when used shall be positioned on the shaft by means of stub or step sleeves. The design shall insure that positive liquid # 3.4.5 Couplinas. 3.4.5
35、.1 Flefible couplings, when required, shall be of all metal construction. - 3.4.5.2 All flexible coupling hubs shall be keyed to the shafts and secured by loclmuts. # For shafts 1 Horizontally flexibly coupled units with inch in diameter and larger, the hubs shall be fitted on a taper. bedplates sha
36、ll have coupling guards provided. for lubrication and inspection. 3.4.6 Priming valve. Guards shall be designed to permit ready access to the coupling 5 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,- NIL-V-lBb3A Li3 W 77777Ob 0273LiLib b 1 i MIL-V-
37、I8683A(SHIPS) 3.4.6.1 Priming valves shall be of the float type and shall permit the flow of air while the pump is being primed, shall close when the water level reaches the valve to prevent water from entering the priming pump, and shallopen whenever the centrifugal pump loses its prime. 3.4.6.2 In
38、let and outlet connections shall be flanged -in accordance with MIL-STD-438 or MIL-STD-777, as applicable. 3.4.7 Seal water tanks. 3.4.7.1 The seal water tank shall be of welded construction with suitable reinforcements to accommodate theweight of the priming pump unit. 3.4.7.2 The tank shall be fit
39、ted with a sight glass, filling connection, drain connection, vent and over- flow connection, and hand hole. 3.5 Identification plates. 3.5.1 Identification lates shall be furnished for each pmp and shall be type A or B in accordance with MIGP-15024 and MGP-150243 5, except that identification plate
40、s of plastic or aluminum are not acceptable. 3.5.1.1 3.5.2 3.5.3 A separate identification plate shall be furnished for the priming valve. Identification plates shall be secured to equipment with corrosion resistant metallic screws. Pump identification plates shall contain data as follows: Manufactu
41、rerte name. Manufacturers model or type and size. Service application (that is, vacuum priming pump). Manufacturers serial number. Salient design characteristics: (1) (2) (3) (4) Brake horsepower. Contract number. Federal stock number. Section for inspectorts stamp. Capacity in cubic feet per minute
42、, Vacuum in inches of mercury. Speed in revolutions per minute. I 3.5.4 Priming valve identification plate shall contain d as follows: (a) Manufacturerta name. (b) Manufacturerte model or size. (c) Manufacturerts serial number. (d) (e) Contract number. (f) Federal stock number. (g) Section for inspe
43、ctorts stamp. Service application (that is, vacuum priming valve). 3.5.5 Esch driving unit and accessory unit shall have an identification plate in accordance with the applicable equipment specification. . 3.6 Drawings. 3.6.1 and III of MILPOOO/. Drawings shall be in accordance with categories E, F,
44、 G and H, form 2 of MIL-D-1000 and types II 3.6.2 Outline drawings shall be furnished covering complete pump units including pump, driver, bedplate and attached accessories. each different pump unit on a contract or order. Separate outline drawings shall be furnished for each contract or order and f
45、or # 3.6.2.1 Performance cmes on preliminary outline drawings as originally submitted to the command or agency coneerned may be calculated curves and shall be so indicated. validated outline drawings shall be based on the performance tests and shall be so indicated. of duplicate pumps are furnished
46、under one contract, all pumps shall be given a performance test, and provided all meet or exceed design conditions, only the performance curve for one unit shall be shown on the drawings. The complete performance curves on the When a number 3.6.3 Pump master drawings shall includesectional assembly,
47、 complete list of material and details of all parts. The section assembly and list of material with references to detail drawings should be on a single 6 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MLV-l8683A(SHIPS) sheet; a& details shall be on
48、one or more additional sheets. master drawing. should be avoided. Several details should be shown on each pump Lhtails of single pump parts on size A sheet, resulting in a multiplicity of drawing sheets, The sectional assembly drawing shall show all assembly clearances. 3.6.4 Subassemblies himiished
49、 as repair parts in lieu of or in addition to individual repair parts shall be recorded on the related outline drawings by reference notes or as additional items on the “List of Material“ of the sectional assembly drawing. 3.6.5 Drawings for drivers and associated equipment shall be in accordance with specifications for those equipmente. 3.6.6 After reconciliation of any comments on drawings, final pump and motor drawings shall be submitted. Mstribution of final drawings shall include
