1、AN AMERICAN NATIONAL STANDARDASME B29.8-2010Revision of ASME B29.8-2002 (R2008)Leaf Chains, Clevises, and SheavesASME B29.8-2010Revision of ASME B29.8-2002 (R2008)Leaf Chains,Clevises, andSheavesAN AMERICAN NATIONAL STANDARDThree Park Avenue New York, NY 10016 USADate of Issuance: March 31, 2011The
2、next edition of this Standard is scheduled for publication in 2016. There will be no addendaissued to this edition.ASME issues written replies to inquiries concerning interpretations of technical aspects of thisStandard. Periodically certain actions of the ASME B29 Committee may be published as Code
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4、he 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 standard was madeavailable for public review and comment t
5、hat 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 take any position with respect to the validity of any paten
6、t 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 assumes any such liability. Users of a code or standard are expresslyadvised that determinati
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8、d.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 reproduced in any form,in an electronic retrieval system
9、 or otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersThree Park Avenue, New York, NY 10016-5990Copyright 2011 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword ivCommittee Roster . vCorrespond
10、ence With the B29 Committee vi1 Leaf Chains . 12 Clevises. 23 Sheaves 24 Lubrication 35 Additional Information . 3Figures1 Assembly Showing 4 H11547 6 Lacing . 32 Assembly Showing 4 H11547 6 Lacing and Parts . 33 Leaf Chain Assemblies and Proportions . 44 Clevis Types . 65 General Clevis Proportions
11、 . 66 General Sheave Proportions 7Tables1 General Chain Dimensions, in. 82 General Chain Dimensions, mm 93 Minimum Ultimate Tensile Strength 104 Dimensions for Anchor Clevises Type B Leaf Chain, in. 115 Dimensions for Anchor Clevises Type B Leaf Chain, mm . 13Nonmandatory AppendixA Supplementary Inf
12、ormation: Lubrication and Maintenance 15iiiFOREWORDFor many years, roller chain manufacturers have furnished a substantial volume of chainsconsisting of link plates assembled on pins without the use of bushings and rollers. These chainsprovide relatively high strength per unit of weight and have fou
13、nd wide usage where sprocketsare not required and high-speed power transmission characteristics are not needed.Previously, variation in link plate thickness, link plate contour, diameter of pins, and the methodof lacing limited its interchangeability and restricted its use. For these reasons the Ass
14、ociationof Roller and Silent Chain Manufacturers appointed a task subcommittee on September 21, 1951to develop this Standard.The scope of the resultant Standard covers the lacing, pin diameter, diameter of link plateholes, link plate contour and thickness, chain widths, and minimum ultimate tensile
15、strengths.The Standard also recommends clevis and sheave design. Supplementary information to guideusers in the application of these chains appeared in the 1958 edition and was deleted in 1960.The 1971 reaffirmation was approved by the American National Standards Institute onSeptember 10, 1971.Prior
16、 to 1975, all B29.8 leaf chain standards included both Type A and Type B leaf chain designs.Type A, the lighter series, was characterized by even or balanced lacing, while Type B, the heavierseries, was shown only with uneven or unbalanced lacing of chain links.During the decade preceding 1975, it b
17、ecame increasingly apparent that the use of Type A leafchain was declining and that it was being used primarily for replacement. Most new designapplications used the heavier Type B design either with the standard uneven lacing or with evenlacing, which was shown as standard only for Type A leaf chai
18、n. The increased use of Type Bchain and the desire to simplify chain standards led the American Chain Association to undertakea revision of B29.8 to:(a) eliminate Type A leaf chain from the standard;(b) add even lacing (balanced) to the Type B chain series;(c) include a 212in. pitch chain to the lis
19、t of Type B chain.These revisions were subsequently included in ANSI B29.8-1977 and approved by the AmericanNational Standards Institute on May 4, 1977.In tabulating dimensional information in this Standard, customary inch-pound units have beenused. Additionally, companion tabulations have been incl
20、uded that provide metric (S.I.) unitconversions of these values in accordance with SI-1, ASME Orientation and Guide for Use of SI(Metric) Units. Certain formulas and relationships have intentionally been presented only incustomary units to eliminate ambiguity between them and the tabulated values.Re
21、visions incorporated in ANSI/ASME B29.8M-1985 provided additional information on clev-ises, clevis pins, minimum sheave size, and lubrication.Revisions incorporated in ASME B29.8M-1993 included changes in format, restatement of thedefinition of Minimum Ultimate Tensile Strength and, most notably, mi
22、nor changes in the standardvalues for maximum pin diameter and the minimum hole diameter. The dimensional changeswere required to allow a direct, error-free conversion between conventional units (inches) andmetric units (millimeters).Revisions incorporated in ASME B29.8-2002 include the elimination
23、of 8H115478 lacing. Tables 1and 2 were revised to show minimum width between outside plates (Lm) and Tables 4 and 5were revised to show the dimensions for an inside clevis. An appendix was added containinginformation on lubrication and maintenance, connect and disconnect, and general inspectioncrite
24、ria. Preload and manufacturers identification marking were added in compliance with therequirements of ISO 4347.Revisions incorporated in ASME B29.8-2010 include upside down rotation of Fig. 1, deletionof the Lmterm and its definition in para. 1.3 and Fig. 3. Also changed is the final sentence ofpar
25、a. 1.4 concerning manufacturers responsibility for ensuring that their chains are properlyconnected; deletion of columns headed “Lm” from Tables 1 and 2; and in Table 1 correcting theWmaxvalues from the BL-5xx chains (the prior values were identical to those for BL-4xx chains).This Standard was appr
26、oved by the American National Standards Institute onNovember 18, 2010.ivASME B29 COMMITTEEChains, Attachments, and Sprockets for PowerTransmission and Conveying(The following is the roster of the Committee at the time of approval of this Standard.)STANDARDS COMMITTEE OFFICERSC. G. Springman, ChairE.
27、 Pawlicki, Vice ChairG. Osolsobe, SecretarySTANDARDS COMMITTEE PERSONNELA. J. Binford, IWIS Drive SystemL. Carrier, Daido Corporation of AmericaD. W. Egbert, Hitachi Maxco Ltd.R. V. Dickey, Alternate, Hitachi MaxcoD. G. Fannin, Emerson Power TransmissionD. Lindsay, Alternate, Emerson Power Transmiss
28、ionW. C. Hall, Ramsey Products Corp.M. Manickam, Webster IndustriesC. A. Norwood, Martin Sprocket however, they shouldnot contain proprietary names or information.Requests that are not in this format may be rewritten in the appropriate format by the Committeeprior to being answered, which may inadve
29、rtently change the intent of the original request.ASME procedures provide for reconsideration of any interpretation when or if additionalinformation that might affect an interpretation is available. Further, persons aggrieved by aninterpretation may appeal to the cognizant ASME Committee or Subcommi
30、ttee. ASME does not“approve,” “certify,” “rate,” or “endorse” any item, construction, proprietary device, or activity.Attending Committee Meetings. The B29 Standards Committee regularly holds meetings thatare open to the public. Persons wishing to attend any meeting should contact the Secretary ofth
31、e B29 Standards Committee.viASME B29.8-2010LEAF CHAINS, CLEVISES, AND SHEAVES1 LEAF CHAINS1.1 DescriptionA leaf chain consists of a series of link plates alter-nately assembled with pins in such a way that the jointis free to articulate between adjoining pitches. Typicalassemblies are depicted in Fi
32、gs. 1 and 2.1.2 Numbering and Marking SystemThe chain described in this Standard shall carry theprefix BL. The last two digits of the number followingthe prefix denote the lacing. The right-hand digit desig-nates the number of link plates in the articulating pitch.The digit to the left of this desig
33、nates the number ofplates in the pin link pitch. The digits to the left of thosetwo digits denote the number of eighths of an inch inthe chain pitch.EXAMPLE: BL523 indicates Type BL leaf chain,58in. pitch witha2H11547 3 lacing; that is, two plates in the pin link pitch and threeplates in the articul
34、ating link pitch.Chains shall be marked with the manufacturers nameor trademark.1.3 Assemblies and General ProportionsVarious assemblies and general proportions for leafchains are depicted in Fig. 3. Dimensions used in thefigures are as follows:CL p clearanceD p pin diameterDmaxp maximum pin diamete
35、rH p link plate heightHmaxp 0.95PP p chain pitchS p hole diameter of articulating link platesSminp approximately Dmax+ 0.0012 in.T p link plate thicknessTmaxp maximum link plate thickness (based on nor-mal steel tolerance). (See Table 1 or 2 forvalues or Tmax.)W p width of chain over pin endsWmaxp w
36、max+ 0.5Dmaxw p width over pin link plateswmaxp (Tmax+ CL) H11547 number of link plates acrosswidth of chainNOTE: Style of heading pins is optional with the manufacturer.11.4 General Chain Dimensions for InterchangeabilityThe dimensions given in Tables 1 and 2 provideguidance that will ensure interc
37、hangeability and compa-tibility with standard design clevises. It is recommendedthat these dimensions be considered for actual minimumand maximum limits. Manufacturers are responsible forensuring that their chains properly connect to the corres-ponding standard clevises.NOTE: Chains from different m
38、anufacturers must never beplaced together within the same application.1.5 Minimum Ultimate Tensile Strength (MUTS)Minimum ultimate tensile strength (MUTS), for chaincovered by this Standard, is the minimum force at whichan unused, undamaged chain could fail when subjectedto a single tensile loading
39、test.WARNING: The MUTS is not a “working load.” The MUTSgreatly exceeds the maximum force that may be safely appliedto the chain.(a) Test Procedure. A tensile force is slowly applied,in a uniaxial direction, to the ends of the chain sample.(b) The tensile test is a destructive test. Even thoughthe c
40、hain may not visibly fail when subjected to theMUTS, it will have been damaged and will be unfit forservice.1.6 Tolerance for Chain LengthNew chains may have a tolerance of 0.031 in./ft(2.58 mm/m) when measured under standard measur-ing load as outlined in para. 1.7.1.7 Measuring LoadThis is the loa
41、d under which a chain is to be measuredfor length. It is equal to 1% of the MUTS. Length mea-surements are to be taken over a length of at least 12 in.(300 mm).1.8 PreloadAll chains shall be preloaded by applying a tensileforce equivalent to at least 30% of the MUTS given inTable 3.ASME B29.8-20102
42、CLEVISESThis section gives recommended design dimensionsof terminal clevises for use with Type B leaf chains.Limiting dimensions herein established are for the pur-pose of ensuring acceptance of chains built in accordancewith foregoing standards.2.1 Design ConsiderationsCare must be exercised in the
43、 manufacture and attach-ment of clevises to ensure equal load distribution acrossthe chain. Failure to do so will seriously reduce the chainload-carrying capacity.It is recommended that the material used for the con-struction of clevises be through-hardening steel.The clevises and pins used to ancho
44、r the chain shallbe of adequate strength to withstand at least the break-ing load of the chain.2.2 Clevis TypesThe clevis may be designed so that the clevis blockfits inside the end plates of the chain, or so that theclevis block fits outside the end plates of the chain, asillustrated in Fig. 4.The
45、required chain end configuration must be speci-fied when ordering cut lengths of chain.2.3 General ProportionsGeneral proportions for clevises are shown in Fig. 5.Dimensions used in the figures are as follows:B pfillet radiusCL pclearancep 0.0015 in. for58in. pitch and smaller, or 0.002 in.for34in.
46、pitch or largerP pchain pitchR pend radiusp 0.5PS pminimum hole diameterT pTmax0.005PTmaxp maximum link plate thicknesst pminimum thickness of outside flange (outsideclevis)p TmaxU pminimum depth of slot for clearancep 0.50P22.4 Dimensions of Anchor ClevisesClevis dimensions are given in Tables 4 an
47、d 5. Lacingfor A, G, K, L, M, N, and O in Fig. 5 is as follows:Lacing Dimensions2 H11547 2 G p 2 H11547 Tmax+4CL + 0.008PL p 2 H11547 T2 H11547 3 G p 3 H11547 Tmax+5CL + 0.008PL p 3 H11547 T3 H11547 4 K p 3(Tmax+ CL)G p 2 H11547 Tmax+3CL + 0.004PA p K + GM p Tmax+2CL + 0.004PL p 2 H11547 TN p (K + L
48、) H11547 0.984 H11547 4 K p 4(Tmax+ CL)G p 2 H11547 Tmax+4CL + 0.008PA p K + GM p GL p 2 H11547 TN p (K + L) H11547 0.974 H11547 6 K p 5(Tmax+ CL)G p 3 H11547 Tmax+5CL + 0.008PA p K + GM p 2 H11547 Tmax+4CL + 0.008PL p 3 H11547 TN p (K + L) H11547 0.986 H11547 6 K p 4(Tmax+ CL)G p 2 H11547 Tmax+4CL
49、+ 0.008PA p K + GM p GL p 2 H11547 TN p 6 H11547 Tmax+4CL 0.008PO p (10 H11547 Tmax+8CL 0.008P) H11547 0.96NOTE: Tolerance on A, G, M, and N p + (0.002P + 0.004) / 0.3 SHEAVESGeneral sheave proportions are depicted in Fig. 6.Dimensions used are as follows:FDp flange diameterp SD + Hmax(see Note)Hmaxp 0.95P (see Table 1)L pminimum distance between flangesp 1.05Wmax(see Table 1)SDp minimum recommended sheave diameterp 5P (see Note)NOTE: Smaller diameters may be used where such practice issupported by testing.ASME B29.8-20104 LUBRICATIONChain must be lubricated period
