ASME B40 200-2008 Thermometers Direct Reading and Remote Reading《直接和远程读数温度计》.pdf

1、Thermometers, Direct Reading and Remote ReadingAN AMERICAN NATIONAL STANDARDASME B40.200-2008(Revision of ASME B40.200-2001)Intentionally left blank ASME B40.200-2008(Revision of ASME B40.200-2001)Thermometers, DirectReading and RemoteReadingAN AMERICAN NATIONAL STANDARDDate of Issuance: August 4, 2

2、008This Standard will be revised when the Society approves the issuance of a new edition. There willbe no addenda or written interpretations of the requirements of this Standard issued to this edition.ASME is the registered trademark of The American Society of Mechanical Engineers.This code or stand

3、ard was developed under procedures accredited as meeting the criteria for American NationalStandards. The Standards Committee that approved the code or standard was balanced to assure that individuals fromcompetent and concerned interests have had an opportunity to participate. The proposed code or

4、standard was madeavailable for public review and comment that provides an opportunity for additional public input from industry, academia,regulatory agencies, and the public-at-large.ASME does not “approve,” “rate,” or “endorse” any item, construction, proprietary device, or activity.ASME does not t

5、ake any position with respect to the validity of any patent rights asserted in connection with anyitems mentioned in this document, and does not undertake to insure anyone utilizing a standard against liability forinfringement of any applicable letters patent, nor assume any such liability. Users of

6、 a code or standard are expresslyadvised that determination of the validity of any such patent rights, and the risk of infringement of such rights, isentirely their own responsibility.Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted asg

7、overnment or industry endorsement of this code or standard.ASME accepts responsibility for only those interpretations of this document issued in accordance with the establishedASME procedures and policies, which precludes the issuance of interpretations by individuals.No part of this document may be

8、 reproduced in any form,in an electronic retrieval system or otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2008 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted i

9、n U.S.A.CONTENTSForeword ivCorrespondence With the B40 Committee vCommittee Roster . viASME B40.3 Bimetallic Actuated Thermometers . 1ASME B40.4 Filled System Thermometers. 22ASME B40.8 Liquid-in-Glass Thermometers . 49ASME B40.9 Thermowells for Thermometers and Electrical Temperature Sensors 69iiiF

10、OREWORDASME B40 Standard Committee is composed of a balanced cross section of manufacturers ofpressure and temperature instruments, users, and interested individuals representing governmentagencies, testing laboratories, and other standards-producing bodies.This Standard has been prepared not only t

11、o provide performance, configuration, and inter-changeability guidelines but also to inform and update the specifier and user regarding producttypes, application, and use. This Standard is a vehicle by which the Committee can transmit tousers the benefits of their combined knowledge and experience r

12、egarding the proper and safeuse of temperature instruments and accessories.Use of this advisory standard is a voluntary matter and shall in no way preclude the manufactureor use of products that do not conform. Neither ASME nor the B40 Committee assumes responsibil-ity for the effect of observance o

13、r nonobservance of recommendations made herein.This Standard is a consolidation and revision of the following standards:(a) B40.3, Bimetallic Actuated Thermometers(b) B40.4, Filled System Thermometers(c) B40.8, Liquid-in-Glass Thermometers(d) B40.9, Thermowells for Thermometers and Elastic Temperatu

14、re SensorsThis Standard provides terminology and definitions, dimensions, safety, construction and instal-lation issues, test procedures, and general recommendations.This Standard supersedes SAMA Standard RC-6-10-1963, RC-4-1-1962, and is intended tosupersede Military Specifications MIL-I-17244, MIL

15、-T-19646, and MIL-T-24272.Suggestions for the improvement of this Standard are welcome. They should be addressed toThe American Society of Mechanical Engineers, Secretary, B40 Standards Committee, Three ParkAvenue, New York, NY 10016-5990.ASME B40.200 was approved by the American National Standards

16、Institute on May 8, 2008.ivASME B40 COMMITTEEStandards for Pressure and Temperature Instrumentsand Accessories(The following is the roster of the Committee at the time of approval of this Standard.)STANDARDS COMMITTEE OFFICERSR. W. Wakeman, ChairJ. Conti, Vice ChairJ. H. Karian, SecretarySTANDARDS C

17、OMMITTEE PERSONNELR. D. Bissell, ConsultantW. J. Browne, Moeller Instrument Company, Inc.J. Conti, AshcroftJ. I. Fellman, Jeffrey FellmanK. Gross, Wika Instrument Corp.R. E. Honer, Jr., Perma-Cal IndustriesF. L. Johnson, JMS Southeast, Inc.J. H. Karian, The American Society of Mechanical EngineersT.

18、 Konen, Naval Ship Systems EngineerSUBCOMMITTEE 200 THERMOMETERJ. Conti, Chair, AshcroftR. D. Bissell, ConsultantJ. I. Fellman, Jeffrey FellmanT. Konen, Naval Ship Systems EngineerM. F. Lancaster, Noshok, Inc.J. G. Murtz, Moeller Instrument Company, Inc.vJ. G. Murtz, Moeller Instrument Company, Inc.

19、M. G. Page, Operating and Maintenance SpecialtiesJ. Scott, Noshok, Inc.M. F. Lancaster, Alternate, Noshok, Inc.D. E. Strawser, Alternate, Naval Sea Systems CommandR. W. Wakeman, Smith Equipment Manufacturing Co., LLCJ. W. Weiss, Weiss Instruments, Inc.R. A. Weissner, Wika Instrument Corp.W. R. Willi

20、ams, AMETEK, Inc./U.S. Gauge DivisionD. Yee, Naval Sea Systems CommandR. W. Wakeman, Smith Equipment Manufacturing Co., LLCJ. W. Weiss, Weiss Instruments, Inc.R. A. Weissner, Wika Instrument Corp.W. R. Williams, AMETEK, Inc./U.S. Gauge DivisionA. V. Yannella, Innovative Development, Inc.CORRESPONDEN

21、CE WITH THE B40 COMMITTEEGeneral. ASME standards are developed and maintained with the intent to represent theconsensus of concerned interests. As such, users of this Standard may interact with the Committeeby proposing revisions, and attending Committee meetings. Correspondence should beaddressed t

22、o:Secretary, B40 Standards CommitteeThe American Society of Mechanical EngineersThree Park AvenueNew York, NY 10016-5990Proposing Revisions. Revisions are made periodically to the Standard to incorporate changesthat appear necessary or desirable, as demonstrated by the experience gained from the app

23、licationof the Standard. Approved revisions will be published periodically.The Committee welcomes proposals for revisions to this Standard. Such proposals should beas specific as possible, citing the paragraph number(s), the proposed wording, and a detaileddescription of the reasons for the proposal

24、, including any pertinent documentation.Proposing a Case. Cases may be issued for the purpose of providing alternative rules whenjustified, to permit early implementation of an approved revision when the need is urgent, or toprovide rules not covered by existing provisions. Cases are effective immed

25、iately upon ASMEapproval and shall be posted on the ASME Committee Web page.Requests for Cases shall provide a Statement of Need and Background Information. The requestshould identify the Code, the paragraph, figure or table number(s), and be written as a Questionand Reply in the same format as exis

26、ting Cases. Requests for Cases should also indicate theapplicable edition(s) of the Code to which the proposed Case applies.Attending Committee Meetings. The B40 Standards Committee regularly holds meetings, whichare open to the public. Persons wishing to attend any meeting should contact the Secret

27、ary ofthe B40 Standards Committee.viASME B40.200-2008 (B40.3)ASME B40.31 Scope . 22 Terminology and Definitions 23 General Recommendations . 54 Safety. 95 Selection Criteria 106 Test Procedures 107 References 11Figures1 Connection, Adjustable Angle 22 Connections, Stem 43 Length, Stem Sections 44 Bi

28、metallic Actuated Thermometer Typical Components . 75 Accuracy Grades . 86 Load Test 12Table1 Vibration Test Amplitudes 13Nonmandatory AppendixA Bimetallic Actuated Thermometers (Supplementary Information) 141ASME B40.200-2008 (B40.3)BIMETALLIC ACTUATED THERMOMETERS1 SCOPEThis Standard is confined t

29、o analog, dial-type bimetal-lic actuated thermometers utilizing helical bimetallic ele-ments that mechanically sense temperature and indicateit by means of a pointer moving over a scale.2 TERMINOLOGY AND DEFINITIONSaccuracy: the conformity of indication to an acceptedstandard or true value. Accuracy

30、 is the difference (error)between the true value and indicated value expressedas a percentage of span. It includes the combined effectsof method, observer, apparatus, and environment. Accu-racy error includes hysteresis and repeatability errorsbut not friction error.accuracy, reference: the accuracy

31、 of a thermometer underreference conditions normal position at 20C 1C(approximately 68F 2F) and 29.92 in. Hg (101.32 kPa)barometric pressure.adjustment, pointer indication: a means of causing achange in indication. The change is approximately equalover the entire scale. Some examples of this type of

32、adjustment are adjustable pointers, rotatable dials, orother similar items. This adjustment, if provided, is gen-erally accessible to the user.bezel: see ring.bimetallic element: see element, bimetallic.bulb: a term sometimes used to describe the temperature-sensitive portion of the stem (see also l

33、ength, sensitiveportion).bushing: a fitting usually provided with external threadsfor attachment to a vessel. A bushing does not have apressure-tight sheath below the external threads.calibration: the process of causing the thermometer toindicate within specified accuracy limits.calibration verifica

34、tion: the checking of a thermometer bycomparison with a given standard to determine the errorat specified points on the scale.cam ring: see ring, cam.case: the housing or container that supports, protects,and surrounds the internals.case, hermetically sealed: for purposes of this Standard, aterm use

35、d to describe a sealed bimetallic thermometer2Fig. 1 Connection, Adjustable AngleStemadjustmentGENERAL NOTE: This illustration is not intended to show design details.meeting the requirements of the prescribed test (seepara. 6.7). Removal of the ring may void the hermeticseal.case, liquid-filled: see

36、 thermometer, liquid-filled.case, sealed: a case that is sealed but need not complywith the hermetic seal test as prescribed in this Standard.case size: see size, case.Celsius: SI unit of temperature measurement (formerlyCentigrade), abbreviation C.Centigrade: see Celsius.conditions, environmental:

37、the conditions, other than pro-cess, that are external to the thermometer includingweather, temperature, humidity, salt spray, vibration,corrosive atmosphere, etc., and could affect the ther-mometers performance or life.connection, adjustable angle: one that allows case rotationof 360 deg and stem a

38、djustment of at least 90 deg (seeFig. 1).connection, back: (90-deg back angle, rear connection) onein which the stem projects from the rear of the case ata 90-deg rear angle to the dial.connection, bottom: (straight form, lower connection) onein which the stem projects downward from the case,paralle

39、l to the dial.connection, left-side: one in which the stem projects fromthe left side of the case, parallel to the dial, as viewedfrom the front.ASME B40.200-2008 (B40.3)connection, right-side: one in which the stem projects fromthe right side of the case, parallel to the dial, as viewedfrom the fro

40、nt.connection, top: one in which the stem projects upwardfrom the case, parallel to the dial (see Fig. 2).connector: the component that joins the stem to the caseassembly.connector, jam nut: a connector using a straight-threadnut and seating part for connecting the thermometer toa bushing, flange, o

41、r thermowell.connector, plain: a connector with no threads.connector, threaded: a connector with fixed threads, usu-ally tapered.connector, union: a threaded fitting that is rotatable rela-tive to the case.correction: the quantity that is algebraically added to anindicated value to obtain the true v

42、alue. The algebraicsign of correction is the opposite of the sign of the error(see also error).corrosion failure: see failure, corrosion.coupling nut: see connector, jam nut.crystal: see window.dampening: a method used to reduce the effects of shockand vibration, usually the application of a viscous

43、 mate-rial to the bimetallic element and/or bearing.dial: the component that contains the scale.dial, anti-parallax: see dial, mirror; dial, multi-plane.dial, dished: see dial, multi-plane.dial, dual-scale: a dial containing two scales with differentunits of measure, such as F and C.dial, graduation

44、s: the individual division marks of a scale.dial, mirror: a dial with a reflector band for the purposeof reducing parallax error.dial, multi-plane: a dial with graduations in approxi-mately the same plane as the pointer (to reduce parallaxerror).dial, rotatable: a feature that allows rotation of the

45、 dialrelative to the pointer.diameter, stem: the outside diameter of the stem.element, bimetallic: the temperature-responsive compo-nent. It is composed of two or more metals mechanicallyassociated in such a way that relative expansion of themetals, caused by temperature change, producesmotion.eleme

46、nt, bimetallic helical: a bimetallic element formed inthe shape of a helix.environmental conditions: see conditions, environmental.error: the difference between the true and indicated val-ues of the variable being measured. A positive error3denotes that the indicated value is greater than the trueva

47、lue (see also correction).error, friction: the difference between the indicated valuesbefore and after the thermometer has been lightlytapped.error, parallax: reading error induced by visualmisalignment.Fahrenheit: U.S. customary unit of temperature measure-ment, abbreviation F.failure, corrosion: f

48、ailure caused by environmental or pro-cess-corrosive chemical attack.failure, over-temperature: failure caused by environmentalor process exposure to temperatures in excess of ratedtemperature limit (see para. 6.3).failure, vibration: failure caused by exposure to vibration(see para. 6.6).friction e

49、rror: see error, friction.friction ring: see ring, friction.graduations, dial: see dial, graduations.hermetically sealed: see case, hermetically sealed.jam nut: see connector, jam nut.length, immersion: the distance from the free end of thestem to the point of immersion in the medium. Thislength must be greater than length, sensitive portion(see para. 3.6.4).length, insertion: the length from the free end of the stemto, but not including, the external threads or other meansof attachment.length, sensitive portion: the length of that section of thestem enclosing the bimetall