1、J MIL-V-178Lt8C 48 m 77777Ob O272720 b m MILITARY SPECIFICATION VALVES, PRESSURE-REDUCING, STEAM SERVICE 27 July 1979 MIL-V-l7848C(SH) SUPERSEDING MIL-V-17848B (SHIPS) 12 November 1968 (See 6.7) This specification is approved for use by the Naval Sea Systems Command, Department of the Navy, and is a
2、vailable for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 $cope. This specification covers self-contained pressure-reducing valves for 1.2 Classification. Pressure-reducing valves shall be of the following classes, and steam service. compositions as specified (see 6
3、.2.1): Class A - Internal pilot operated Class B - Inverted, gas loaded, liquid sealed Class C - Spring loaded Composition A - 2-1/4 percent chromium 1 percent molybdenum (maximum temperature Composition B - 1-1/4 percent chromium 1/2 percent molybdenum (maximum temperature Composition D - Carbon st
4、eel (maximum temperature 7759F (see 3.5.6). Pressure-temperature ratings shall be as specified in 3.5.6, and as specified (see 6.2.1). 1050OF (see 3.5.6) lOOOOF (see 3.5.6) 2. APPLICABLE DOCUMENTS 2.1 Issues of documents. The following documents, of the issue in effect On date Of invitation-iz or re
5、quest for proposal, form a part of this specification to the extent specified herein. SPECIFICATIONS MILITARY MIL-V-3 - Valves, Fittings, and Flanges (Except for Systems Indicated Herein); MIL-R-196 - Repair Parts for Internal Combustion Engines, Packaging of. MIL-S-901 - Shock Tests, H.I. (High-Imp
6、act): Shipboard Machinery, Equipment MIL-R-2765 - Rubber Sheet Strip, Extruded, and Molded Shapes, Synthetic, Oil Resistant. MIL-P-15024 - Plates, Tags and Bands for Identification of Equipment. MIL-P-15024/5 - Plates, Identification. MIL-R-17131 - Rods and Powders, Welding, Surfacing. MIL-G-21032 -
7、 Gaskets, Metallic-Asbestos, Spiral Wound. MIL-1-45208 - Inspection System Requirements. Packaging of. and Systems, Requirements For. STANDARDS FEDERAL FED-STD-H28 - Screw-Thread Standards for Federal Services. Beneficial comments (recommendations, additions, deletions) and any pertinent data which
8、may be of use in improving this document should be addressed to: Commander, Naval Sea Systems Command, SEA 3112, Department of the Navy, Washington, DC 20362 by using the self-addressed Standardization Document Improvement Proposal (DD Form 1426) appearing at the end of this document or by letter. F
9、SC 4820 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-l7840C(SII) MILITARY MIL-STD-167-1 - Mechanical Vibrations of Shipboard Equipment (Type f - Environ- MIL-STD-271 - Nondestructive Testing Requirements for Metals. mental and Type II - Inte
10、rnally Excited). MIL-STD-2.78 - Fabrication Welding and Inspection: and Casting Inspection and the United States Navy. Repair for Machinery, Piping and Pressure Vessels in Ships of Control and Identification and HI-Shock Test Requirements for Piping System Components for Naval Shipboard Use. MIL-STD
11、-798 - Nondestructive Testing, Welding, Quality Control, Material M916142 - Boss, Gasket Seal Straight Thread Tube Fitting, Standard Dimensions For. (Copies of specifications, standards, drawings, and publications required by contractors in connection with specific acquisition functions should be ob
12、tained from the contracting activity or as directed by the contracting officer.) the extentwi- Unless otherwise indicated, the issue in effect on date of invitation for bids or request for proposal shall apply. 2.2 Qther ubllcations. The following documents form a part of this specification to AMERI
13、CAN NATIONAL STANDARDS INSTITUTE (ANSI) D1.12 - Class 5 Interference-Fit Thread. 818.2.1 - Square and Hex Bolts and Screws, Including Askew Head Bolts, Hex Cap l316.5 - Steel Pipe Flanges, Flanged Valves, and Fittings. Screws, and Lag Screws. 1430 Broadway, New York, NY 10018.) (Application for copi
14、es should be addressed to the American National Standards Institute, AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) A105 - Forgings, Carbon Steel, for Piping Components. A182 - Forged or Rolled Alloy-Steel Pipe Flanges, Forged Fittings, an9 Valves A193 - Alloy-Steel and Stainless Steel Bolting Ma
15、terials for High-Temperature A194 - Carbon and Alloy Steel Nuts for Bolts for High-pressure and High- A216 - Carbon-Steel Castings Suitable for Fusion Welding for High-Temperature A217 - Martensitic Stainless Steel and Alloy Steel Castings for Pressure- and Parts for High-Temperature Service. Servic
16、e, Temperature Service. Service. Containing Parts Suitable for High-Temperature Service. Materiala, 1916 Race Street, Philadelphia, PA 19103.) (Application for copies should be addressed to the American Society for Testing and (Technical society and technical association specifications and standards
17、 are generally available for reference from libraries. They are also distributed among technical groups and using Federal agencies,) 3, REQUIREMENTS products wFich are quafified for listing on the applicable qualified products list at the time set: for opening o bids (see 4.3 and 6.3). production, I
18、I samm shafr me-fied in 4.5 (see 6.4). 3.1 Qualification. Class A and B valves furnished under this specification shall be 3.2 Sample for first article ins ction, For class C valves, prior to beginning The followms-cription of the classes A, B, and C: 3.3 Valve descri tions. Valves shall be of the s
19、elf-contained, internal operated type. (a) Class A (internal pilot: o erated) Downstream pressure feedback is sensed m spring-loa rating, the outlet pressure in a dead-end volume representing not more than 100 diameterS.of the downstream pipe, shall not rise more than 10 lb/in2 in a 1 hour period. c
20、hamber for class B vdsm be tested with.steam or air to the maximum working pressure to check for external leakage. There shall be no external leakage which can be detected by use of a mirrored surface (for steam) or bubble fluid (for air). 4.3.5 Dead-end test. Using steam or air, with an inlet press
21、ure equal to the nominal 4.3.6 External leaka e test. Pressure containing parts, including the diaphragm 4.3.7 Performance test. The valve shall be subjected to the tests specified in 4.3.7.1 through 4.3.7.3. The delivered pressure shall at all times hold within the limits of plus or minus 5 percent
22、 or plus or minus 2 lb/in2, whichever is greater. There shall be no evidence of hunting, chattering or any other unstable or unsatisfactory operation of the valve during any portion of these tests. The test specified in 4.3.7.1 and 4.3.7.2 shall be r conducted with the valve set at the upper and low
23、er limits of the set pressure range (see 3.5.12). 4.3.7.1 Flow-droop test. The flow shall be varied from lock-up to the maximum flow r rating of the valve in not mre than 15 seconds and from the maximum flow rating to lock-up in not more than 15 seconds. This test shall be Conducted Under the follow
24、ing sets of conditions: (a) Maximum inlet pressure - lowest set pressure. (b) Minimum inlet pressure - lowest set pressure. (c) Minimum inlet pressure - highest set pressure. (d) Maximum inlet pressure - highest set pressure. The maximum inlet pressure for these tests shall be equal to the rating of
25、 the valve and the minimum inlet pressure for these tests shall be equal to 75 percent of the rating of the valve. 4.3.7.2 Inlet pressure transient. With a constant flow demand equal to 10, 50, and of the inlet rating in not more than 5 seconds and from 100 percent to 75 percent of the 100 percent o
26、f the maximum, the inlet pressure shall be.varied from 75 percent to 100 percent inlet rating in not mre than 5 seconds. 4.3.7.3 Endurance test. Following the tests of 4.3.7.1 and 4.3.7.2, the valve shall be subjected to a 20 houeerational test to check functioning and performance. 4.3.8 Hi h-im act
27、 shock test. The valve shall be subjected to the high-impact mechanical reqzireznts forradeA, class I of MIL-S-901. MIL-STD-798 shall be used for guidance for test procedures. 4.3.9 Vibration test. The valve shall be vibration tested in accordance with type I of MIL-STD-167-1. 4.3.9, the tefiaKshal1
28、 be disassembled and visually and dimensionally examined. Any damage, excessive wear, or signs of galling or pitting shall be cause for rejection. 4.3.10 Post test examination. After completion of the tests specified in 4.3.3 through 4.4 First unit examination and tests. The first valve of the sann?
29、 class (class A or B) and ratingiiintended for the SE m shipboard application, furnished under a contract or order shall undergo the first unit examination and tests specified in 4.4.1 through 4.4.6. First unit examination and tests will be waived on subsequent orders for the same equipment. and bas
30、ic application. First unit tests may also be waived where the manufacturer has sufficient verifiable evidence based on test data or previous shipboard experience or both with the same or similar application to satisfactorily demonstrate that the valve proposed will meet all contract requirements and
31、 is suitable for the intended shipboard application.; Subsequent valves of the same class and rating and intended for thesame basic shipboard application furnished shall undergo quality conformance inspection specified in 4.6 4.4.1 Examination. Valves shall be examined as specified in 4.3.2. 4,4.2 H
32、ydrostatic test. Valves shall be hydrostatic tested as specified in 4.3.4. 4.4.3 Dead-end test. Valves shall be dead-end tested as specified in 4.3.5. 9 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-with the valve set at th-per and lower setting of
33、 the adjustable set pressure range required by the applicatin (see 6.2.1). The maximum inlet temperature, the range of operating inlet: pressures, the maximum rate of change of the inlet pressure, the maximum flow capacity required, and the maximum rate of change of flow demand shall be as specified
34、 (see 6.2.1) to meet the application requirements. The required accuracy of regulation shall be maintained and there shall be no evidence of hunting, chattering, or any other unstable or unsatisfactory operation o the valve over any portion of the required operational range of the valve. rating and
35、bacdate specified (see 6.2.1) . This test shall be ronducted under the following 50t5 of conditionst 4.4.5 Performance test. The teats specified in 4.4.5.1 and 4.4.5.2 shall be conducted 4.4.5,l Flow-droo =. The flow shall be varied from lock-up to the maximum flow (a) Maximum inlet pressure - lowes
36、t set pressure. (b) Minimum inlet pressure - lowest set pressure. (c) Minimum inlet pressure - highest set pressure. (d) Maximum inlet pressure - highest set pressure. 100 percent ofTm!the inlet pressure shall be varied over the specified range at the maximum rate specified (see 6.2.1). 4.4.5.2 Inle
37、t ressure transient. With a constant flow demand equal to 10, 50, and 4.4.6 Nondestructive tests. Nondestructive tests shall be conducted as specified in 4.3.3. of! the examian specih3.2 and 4.5.3 and tests specified in 4.4.1 through 4.4.6 and 4.5.1 and 4.5.2. Each test valve shall be submitted with
38、 the items specified in 4.3.1.1, subjected to a 5-hour Fational test to check functioning and performance. 4.5 First: article ins ectlon. First article inspection for class C valves shall consist 4.5.1 Endurance test. Following the tests specified in 4.4.5, class C valves shall be shall be as when r
39、equired (see 3.5.11). (e) Whether internal or external reduced pressure sensing (f) Charging equipment to be supplied with class B valves (9) Accuracy of regulation required (see 3.6.1). (h) Minimum and maximum inlet gage pressures (lb/in ) (see (i) Range of adjustment for valves (see 3.6.3). (j) If
40、 provisioning data is required (see 3.8.1.2). 3.5.13.1). line is required (see (see 3.5.13.2). 3.6.2 and 4.4.5). 11 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-V-1784OC (SH) (k) Quality assurance requirements (see 4.1.1). (1) 1.laximum rate o
41、f inlet pressure variation (lb/in per second) where known (see (m) Maximum inlet steam temperature (OF) (see 4.4.5). (n) Maximum rate of flow demand variation (pounds per hour per second) where (o) Maximum and minimum capacity required lb/h (see 4.4.5.1). (pl Level of preservation, packaging, and le
42、vel of packing and marking required (q) When “loose-fill“ is permitted (see 5.2.1). 4.4.5 and 4.4.5.21, known (see 4.4.5). (see 5.1 and 5.3). the provisiom the “Requirements for Data“ of the Defense Acquisition Regulation (DAR), the data identified below, which are required to be developed by the co
43、ntractor, as specified on an approved Data Item Description (DD Form 16641, and which are required to be delivered to the Government, should be selected and specified on the approved Contract Data Requirement List (DD Form i423) and incorporated in the contract. When the provisions of the “Require-
44、mnts for Data of the DAR are not invoked in a contract, the data required to be developed by the contractor and required to be delivered to the Government should be selected from the list below and specified in the contract. 6.2.2 Data requirements. When this specification is used in a contract whic
45、h invokes Parirgrnph Data requirements Applicable DID Option 3.8.1 and Drawings, engineering and DI-E-7031 Level 2 3.8.1.1 nssociatscl lints Design activity designation - contractor Drawing number - contractor Delivery of hard copies - contracting activity 3.8.1.2 Supplementary provisioning DI-V-700
46、0 “ teehnical documentation (SPTD) 3.8.2 Manual, technical , DI-“204 3 Type I of MIL-M-15071 preliminary (Copies sf data item descriptions required by the contractors in connection with specific? acquisition functions should be obtained from the contracting activity or as of invitation for bids or r
47、equest for proposal shall apply.) diractod by the Contracting officer. Unless otherwise indicated, the issue in effect on date 6.2.2.1 The data requirements of 6.2.2 and any task in section 3, 4, or 5 of the specification required to be performed to meet a data requirement may be waived by the csntr
48、actin/rrcquisition activity upon certification by the offeror that identical data were submitted by the offeror and accepted by the Government under a previous contract for identical item acquired to this specification. This does not apply to specific data which previously (for example, test: report
49、s). nay be required for each contract regardless of whether an identical item has been supplied 6.2.2.2 Where the Government has limited rights in the data shown on the drawings, as nay be marked with a legend. If used, the Limited Rights Legend“ of DAR should be used. daterminod by the contractual provisions reaarding rights in technical data, the drawings 6.3 With respect to products requiring qualification, awards will be made only for products which are at the time set for opening of bids, qualified for inclusi
