1、Designation: F2934 12 (Reapproved 2018) An American National StandardStandard Specification forCircular Metallic Bellows Type Expansion Joint for HVACPiping Applications1This standard is issued under the fixed designation F2934; the number immediately following the designation indicates the year ofo
2、riginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification establishes the minimum require-ments for
3、 the mechanical design, manufacture, inspection andtesting of circular metallic bellows-type expansion joints usedto absorb the dimensional changes resulting from pipingthermal expansion or contraction, as well as the movements ofterminal equipment and supporting structures.1.2 Additional or better
4、features, over and above the mini-mum requirements set by this specification, are not prohibitedby this specification.1.3 The layout of many piping systems provides inherentflexibility through natural changes in direction so that anydisplacements produce primarily bending or torsional strains,within
5、 acceptable limits. Where the system lacks this inherentflexibility the designer should then consider adding flexibilitythrough the use of metallic bellows-type expansion joints.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalc
6、onversions to SI units that are provided for information onlyand are not considered standard.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and en
7、vironmental practices and deter-mine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Stan
8、dards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASME/ANSI Standards:2B16.25 Butt Welding EndsB16.5 Pipe Flanges and Flanged FittingsB31.1 Power Piping Code2.2 ASME Standard:3Section IX Welding and Brazing
9、 Qualifications2.3 EJMA Standard:4Standards of the Expansion Joint ManufacturersAssociation2.4 Pipe Fabrication Institute Standard:5ES-3 Fabrication Tolerances3. Terminology3.1 Expansion joint definitions shall be in accordance withthose in the EJMA standards.3.2 Definitions:3.2.1 double expansion j
10、ointexpansion joint consisting oftwo bellows joined by a common connector.3.2.1.1 DiscussionThe common connector is anchored tosome rigid part of the installation by means of an anchor base.The anchor base may be attached to the common connectoreither at installation or at time of manufacture. This
11、anchorbase is an intermediate anchor and is not usually designed towithstand the full thrust load of the piping run. The dualexpansion joint is installed in the middle of the piping run andthe thrust is directed to the middle. Each bellows acts as asingle expansion joint and absorbs the movement of
12、the pipesection in which it is installed independently of the otherbellows.1This specification is under the jurisdiction of ASTM Committee F25 on Shipsand Marine Technology and is the direct responsibility of Subcommittee F25.11 onMachinery and Piping Systems.Current edition approved March 1, 2018.
13、Published April 2018. Originallyapproved in 2012. Last previous edition approved in 2012 as F2934 12.DOI:10.1520/F2934-12R18.2Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.3Available from American Society of Mechanical E
14、ngineers (ASME), ASMEInternational Headquarters, Two Park Ave., New York, NY 10016-5990, http:/www.asme.org.4Available from Expansion Joint Manufacturers Association (EJMA), 25 NorthBroadway Tarrytown, NY 10591, http:/www.ejma.org.5Available from Pipe Fabrication Institute (PFI), 511 Ave. of America
15、s, #601,New York, NY 10011, http:/www.pfi-institute.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established i
16、n the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.13.2.2 externally pressurized expansion jointtypically usedfor straight runs of pipe accommodating axial movement,
17、 andincorporate an all stainless steel flexible bellows, an internalguide ring/sleeve, an enclosure with end plates at each end.3.2.2.1 DiscussionExternally pressurized expansion jointsare typically configured with a service pipe extending throughthe bellows, and the bellows attaching to the end of
18、the servicepipe and the end plate. The external side of the bellows isexposed to the pressure of the medium being conveyed by theservice pipe and the inside of the bellows is exposed toatmosphere.3.2.3 gimbal expansion jointexpansion joint designed topermit angular rotation in any plane by the use o
19、f two pairs ofhinges affixed to a common floating gimbal ring.3.2.3.1 DiscussionThe gimbal ring, hinges, and pins aredesigned to restrain the thrust of the expansion joint as a resultof internal pressure and extraneous forces, where applicable.3.2.4 hinged expansion jointexpansion joint containingon
20、e bellow designed to permit angular rotation in one planeonly by the use of a pair of pins through hinge plates attachedto the expansion joint ends.3.2.4.1 DiscussionThe hinges and hinge pins are designedto restrain the thrust of the expansion joint as a result ofinternal pressure and extraneous for
21、ces. Hinged expansionjoints should be used in sets of two or three to functionproperly.3.2.5 internally pressurized expansion jointtypically in-corporates an all stainless steel flexible bellows containing thepressure on the internal side.3.2.5.1 DiscussionInternally pressurized expansion jointscan
22、be configured to accommodate a wide range of move-ments.3.2.6 pressure balanced expansion jointexpansion jointdesigned to absorb axial movement or lateral deflection, orboth, while restraining the pressure thrust by means of tiedevices interconnecting the flow bellows with an opposedbellows also sub
23、jected to line pressure.3.2.6.1 DiscussionThis type of expansion joint is usuallyintended for use where a change of direction occurs in a run ofpiping. The flow end of a pressure balanced expansion jointsometimes contains two bellows separated by a commonconnector, in which case it is called a unive
24、rsal pressurebalanced expansion joint. Inline pressure balanced expansionjoints do not require a change in direction of the piping.3.2.7 single expansion jointsimplest form of expansionjoint, consisting of single bellows construction, designed toabsorb all movement of the pipe section in which it is
25、 installed.3.2.8 swing expansion jointexpansion joint designed toabsorb lateral deflection or angular rotation, or both, in oneplane.3.2.8.1 DiscussionPressure thrust and extraneous forcesare restrained by the use of a pair of swing bars, each of whichis pinned to the expansion joint ends.3.2.9 univ
26、ersal expansion jointexpansion joint containingtwo bellows joined by a common connector for the purpose ofabsorbing any combination of axial movement, lateraldeflection, and angular rotation.3.2.9.1 DiscussionUniversal expansion joints are usuallyfurnished with control rods to distribute the movemen
27、t betweenthe two bellows of the expansion joint and stabilize thecommon connector when a universal expansion joint is usedfor lateral movement only and installed at a change in directionof the piping and is intended to absorb the thermal growth ofthat section of the piping, it must be designed with
28、tie rodssuitable to absorb the full pressure thrust of the expansion joint.4. Ordering Information4.1 An expansion joint is a unique product and must bespecifically designed for the intended service. It is the respon-sibility of the piping system designer to supply sufficientengineering data necessa
29、ry for the complete design. Theinformation compiled by the piping system designer must becomplete and contain all pertinent data detailing the conditionsunder which the expansion joint is expected to operate.4.2 Orders for each expansion joint shall include the fol-lowing information:4.2.1 Title, de
30、signation number, and latest revision of thisspecification.4.2.2 SizeThe nominal pipe diameter or specific ductingdiameter.4.2.3 Type of Expansion JointSingle, double, universal,guided, hinged, gimbal, swing, or pressure balanced.4.2.4 Flow Characteristics:4.2.4.1 Flow MediumIndicate whether the med
31、ium is gasor liquid.4.2.4.2 Flow velocity, medium density, or viscosity, orcombination thereof.4.2.4.3 Flow direction.4.2.5 Pressure in psig (N/mm2)Design, operating, and testpressures.4.2.6 Temperate in F (C)Design, operating, and instal-lation temperatures.4.2.7 MovementAxial (extension, compressi
32、on); lateral(single plane, multiplane); angular; torsional (to be avoided).Differentiate between start-up, operational, or field installationtolerance movements.4.2.8 MaterialsMaterial types (including that for the bel-lows shall be specified by the purchaser (see 5.1 for materialrestrictions).4.2.9
33、 Internal LinerLiner shall be specified when neededbecause of flow velocity or other flow conditions. Specificcriteria for liners is shown in Section C-3 of the EJMAStandards (see 6.6).4.2.10 External CoverTo protect personnel having closeaccess to the bellows, when thermal insulation is to be added
34、 inthe field, or when external mechanical damage is possible (see6.5).4.2.11 End FittingsThe type of end connections such asflanged, threaded, or others to match the mating piping orterminal equipment.4.2.12 AccessoriesSpecify what accessories are requiredand the conditions under which they operate.
35、 Consider itemssuch as insulation lugs, tie, limit, or control rods, pantographiclinkages, trunions, gimbals, drains, purge connections, anchorbases, and interplay monitoring devices.F2934 12 (2018)24.2.13 Dimensional LimitationsIf space limitations existspecify the maximum overall length, maximum o
36、utsidediameter, minimum inside diameter, and installation toler-ances.4.2.14 Operating ForcesSpecify calculated bellowsspring forces and pressure thrust forces if they are required forsubsequent anchor design or other piping systems analysis. Ifthere are maximum allowable values, these must also bes
37、pecified.4.2.15 Installation Positionhorizontal, vertical (flow up ordown). Specify if liner drainage holes are required.4.2.16 Cycle Life RequirementsSpecify an anticipatednumber of thermal cycles over the intended life of theexpansion joint.4.2.17 Testing RequirementsSpecify testing requirementsin
38、 addition to the hydrostatic test required by 9.4 (for example,vacuum testing, testing at operating temperature).4.2.18 Inspection RequirementsSpecify inspection re-quirements in addition to the inspection required by Section 9(that is, radiographic, fluorescent penetrant, or mass spectrom-eter).4.2
39、.19 Piping Code RequirementsSpecify any piping ordesign code that must be used as the basis for design inaddition to those specified in 5.2.4.2.20 Special RequirementsSpecify the magnitude ofspecial system conditions such as vibration, shock, or hydraulicsurge. When vibration is present the customer
40、 shall provide thenatural frequency of the equipment. The design engineer shalldesign the bellows natural frequency to be less than23 of thesystem frequency or two times greater than the system fre-quency.4.2.21 Shipping RequirementsSpecify whether specialpacking is required including protection for
41、 extended outsidestorage, export handling, or special lifting considerations forheavy or large assemblies.4.2.22 Piping DrawingIn addition to specifying the aboveinformation it would be beneficial to provide a drawing of theproposed piping system.4.2.23 Supplementary RequirementsSpecify any addi-tio
42、nal requirements not identified herein.4.3 Fig. 1 and Fig. 2 should be used as a guide in orderingexpansion joints to this specification.5. Materials and Manufacture5.1 Materials:5.1.1 Pressure-containing parts shall be manufactured frommaterial specifications and grades listed in ANSI B31.1. Endcon
43、nection materials shall have in service properties similar tothe bellows material. Flanges shall meet ANSI B16.5.5.1.2 All other materials of construction shall be of the typespecified by the user and shall conform to an ASTM or ASMEmaterial specification. Materials not identified by the orderingdat
44、a shall be of the manufacturers standard and of the samequality used for the intended purpose in commercial practice.5.1.3 Materials used shall be free from defects that wouldadversely affect the performance of the expansion joint.5.1.4 All material incorporated in the work covered by thisspecificat
45、ion shall be new. The use of rebuilt or used productsis not allowed under this specification.5.1.5 Materials for hinge or gimbal hardware, or othersliding parts, shall be chosen to minimize galling of thecontacting parts.5.2 Manufacture:5.2.1 Expansion joints shall be designed and fabricated inaccor
46、dance with requirements set forth in the ordering data andthe EJMA Standards.5.2.2 Nonstandard flanges shall be designed and fabricatedin accordance with Appendix 2 of Section VIII, Division 1, ofthe ASME Code. Flanges machined from plate shall not beused at pressures exceeding 150 psi (1034 kPa) an
47、d tempera-tures exceeding 450F (232C). Hubbed flanges machinedfrom plate or bar stock shall meet the requirements ofAppendix 2, Paragraph 2-2(d) of Section VIII, Division 1, ofthe ASME Code.5.2.3 All welding shall be accomplished in accordance withANSI B31.1.5.2.4 Welding personnel and welding proce
48、dures shall bequalified in accordance with the applicable sections of SectionIX of the ASME Code.5.2.5 All fabrication details not covered by the referencedcodes and standards shall be taken from the appropriate ANSIstandard. If no standard applies, accepted industry practiceshall govern.5.2.6 The b
49、ellows shall be of tested and proven convolutiongeometry.6. Other Requirements6.1 The details of design, material supply, fabrication, andtesting of the complete product are the responsibility of themanufacturer unless specific details are requested by thepurchaser.6.2 The specified normal operating movements (axial,lateral, and angular) shall be available concurrently. Thespecified lateral and angular movements shall be available oneither side of the expansion joint centerline.6.3 Internal sleeves, external covers, and all attached har
