ASHRAE 126-2016 Method of Testing HVAC Air Ducts.pdf

1、ANSI/ASHRAE/SMACNA Standard 126-2016(Supersedes ANSI/ASHRAE/SMACNA Standard 126-2008)Method of TestingHVAC Air DuctsApproved by ASHRAE on June 30, 2016, by the Sheet Metal and Air Conditioning Contractors National Association on May9, 2016, and by the American National Standards Institute on July 1,

2、 2016.ASHRAE Standards are scheduled to be updated on a five-year cycle; the date following the Standard number is the year ofASHRAE approval. The latest edition of an ASHRAE Standard may be purchased on the ASHRAE website (www.ashrae.org)or from ASHRAE Customer Service, 1791 Tullie Circle, NE, Atla

3、nta, GA 30329-2305. E-mail: ordersashrae.org. Fax: 678-539-2129. Telephone: 404-636-8400 (worldwide) or toll free 1-800-527-4723 (for orders in US and Canada). For reprintpermission, go to www.ashrae.org/permissions. 2016 ASHRAE ISSN 1041-2336SPECIAL NOTEThis American National Standard (ANS) is a na

4、tional voluntary consensus Standard developed under the auspices of ASHRAE. Consensus is definedby the American National Standards Institute (ANSI), of which ASHRAE is a member and which has approved this Standard as an ANS, as“substantial agreement reached by directly and materially affected intere

5、st categories. This signifies the concurrence of more than a simple majority,but not necessarily unanimity. Consensus requires that all views and objections be considered, and that an effort be made toward their resolution.”Compliance with this Standard is voluntary until and unless a legal jurisdic

6、tion makes compliance mandatory through legislation. ASHRAE obtains consensus through participation of its national and international members, associated societies, and public review.ASHRAE Standards are prepared by a Project Committee appointed specifically for the purpose of writing the Standard.

7、The ProjectCommittee Chair and Vice-Chair must be members of ASHRAE; while other committee members may or may not be ASHRAE members, allmust be technically qualified in the subject area of the Standard. Every effort is made to balance the concerned interests on all Project Committees. The Senior Man

8、ager of Standards of ASHRAE should be contacted fora. interpretation of the contents of this Standard,b. participation in the next review of the Standard,c. offering constructive criticism for improving the Standard, ord. permission to reprint portions of the Standard.DISCLAIMERASHRAE uses its best

9、efforts to promulgate Standards and Guidelines for the benefit of the public in light of available information and acceptedindustry practices. However, ASHRAE does not guarantee, certify, or assure the safety or performance of any products, components, or systemstested, installed, or operated in acc

10、ordance with ASHRAEs Standards or Guidelines or that any tests conducted under its Standards or Guidelineswill be nonhazardous or free from risk.ASHRAE INDUSTRIAL ADVERTISING POLICY ON STANDARDSASHRAE Standards and Guidelines are established to assist industry and the public by offering a uniform me

11、thod of testing for rating purposes, bysuggesting safe practices in designing and installing equipment, by providing proper definitions of this equipment, and by providing other informationthat may serve to guide the industry. The creation of ASHRAE Standards and Guidelines is determined by the need

12、 for them, and conformanceto them is completely voluntary.In referring to this Standard or Guideline and in marking of equipment and in advertising, no claim shall be made, either stated or implied,that the product has been approved by ASHRAE.ASHRAE Standing Standard Project Committee 126Cognizant T

13、C: 5.2, Duct DesignSPLS Liaison: Peter SimmondsKevin J. Gebke*, Chair Herman F. Behls* Ralph Koerber, I*Alex M. Kouvolo*, Vice-Chair Eli P. Howard, III* Stephen R. Wiggins*Gary L. Miller, Secretary* Denotes members of voting status when the document was approved for publicationASHRAE STANDARDS COMMI

14、TTEE 20162017Rita M. Harrold, Chair Julie M. Ferguson Cyrus H. NasseriSteven J. Emmerich, Vice-Chair Michael W. Gallagher David RobinJames D. Aswegan Walter T. Grondzik Peter SimmondsNiels Bidstrup Vinod P. Gupta Dennis A. StankeDonald M. Brundage Susanna S. Hanson Wayne H. Stoppelmoor, Jr.Waller S.

15、 Clements Roger L. Hedrick Jack H. ZarourDrury B. Crawley Rick M. Heiden William F. Walter, BOD ExOJohn F. Dunlap, Srinivas Katipamula Patricia Graef, COJames W. Earley, Jr. Arsen K. MelikovKeith I. Emerson R. Lee Millies, Jr.Stephanie C. Reiniche, Senior Manager of StandardsCONTENTSANSI/ASHRAE/SMAC

16、NA Standard 126-2016,Method of Testing HVAC Air DuctsSECTION PAGEForeword .21 Purpose.22 Scope23 Definitions and Symbols24 Instrumentation .35 Tests .36 Leakage Test 37 Structural Tests.48 Durability Tests .139 Report .1310 References14Informative Annex ACommentary15Informative Annex BLeakage Test S

17、etups and Example Problem16Informative Annex CRecommended Acceptance Criteria .19Informative Annex DBibliography 20NOTEApproved addenda, errata, or interpretations for this standard can be downloaded free of charge from the ASHRAEwebsite at www.ashrae.org/technology. 2016 ASHRAE1791 Tullie Circle NE

18、 Atlanta, GA 30329 www.ashrae.org All rights reserved.ASHRAE is a registered trademark of the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.ANSI is a registered trademark of the American National Standards Institute.2 ANSI/ASHRAE/SMACNA Standard 126-2016(This forewor

19、d is not part of this standard. It is merelyinformative and does not contain requirements necessaryfor conformance to the standard. It has not been pro-cessed according to the ANSI requirements for a standardand may contain material that has not been subject topublic review or a consensus process. U

20、nresolved objec-tors on informative material are not offered the right toappeal at ASHRAE or ANSI.)FOREWORDFirst published in 2000, Standard 126 is a joint project ofASHRAE and the Sheet Metal and Air Conditioning Contrac-tors National Association (SMACNA). It was created to pro-vide methods of test

21、ing to determine the strength anddurability characteristics of HVAC ducts under various load-ing and environmental conditions. The intent of Standard 126is to address all duct shapes and materials. To the projectcommittees knowledge, no other publication addresses all ofthe structural and durability

22、 tests as comprehensively as thisstandard, although individual tests are covered under otherstandards. A standardized set of comprehensive tests is used toensure that products meet minimum structural requirements,and to allow products to be compared to one another. Suchtests should simulate structur

23、al stresses that the duct willexperience in service and facilitate the application of safetyfactors. These tests include pressurizing the ductwork, apply-ing superimposed loads, dropping weighted implements forimpact or puncture, applying tension to the duct, bendingflexible duct 180 degrees, subjec

24、ting the ductwork to tempera-ture and humidity changes, and bursting or collapsing theductwork under pressure. After an individual test or a seriesof tests, leakage tests may be conducted to determine theeffect of a structural or durability test on a specimen. Duringa test or series of tests, the du

25、ctwork is observed to determineif there is degradation and permanent damage.Pass/fail criteria are determined by the sponsoringagency, code officials, or other users of this standard. Recom-mended acceptance criteria are provided in InformativeAnnex C.1. PURPOSEThis standard provides laboratory test

26、 procedures for the eval-uation of HVAC air ducts.2. SCOPE2.1 This standard shall be used to determine the structuralstrength, dimensional stability, durability, and leakage charac-teristics of HVAC air ducts.2.2 This standard does not address the following:a. Fittingsb. Effects of aerosols, solid p

27、articulates, corrosive environ-ments, or combustibilityc. Long-term effects of extended serviced. Seismic qualificationse. Underground ductsf. Plenums and equipment casingsg. Supports for ductwork and fittings3. DEFINITIONS AND SYMBOLS3.1 Definitionsaccuracy: the degree of conformity of an indicated

28、 value toan accepted standard value, or true value. The degree of inac-curacy is known as “measurement error” and is the sum ofbias error and precision error.bias error (systematic error): the difference between the trueor actual value to be measured and the indicated value fromthe measuring system

29、that persists and is usually due to theparticular instrument or technique of measurement. Theseerrors are corrected through calibration.density of standard air (s): 1.204 kg/m3.duct, HVAC: duct and fittings used for conveying air in resi-dential, commercial, institutional, and industrial heating, ve

30、n-tilating, and air-conditioning systems.joint: a connection of duct surface elements that is primarilyintended to connect lengths of ductwork, to join intersectingducts, or to join ducts and equipment.leakage: the volumetric flow rate required to maintain a con-stant static pressure in a test speci

31、men. leakage class: leakage of ductwork, L/s per Pa0.65per m2ofduct surface area.precision: the closeness of agreement among repeated mea-surements of the same characteristic by the same methodunder the same conditions.random error (precision error): a statistical error that iscaused by chance and i

32、s not recurring.sealant: a material or product used to seal longitudinal ductseams, transverse duct joints, and ductwork penetrations. Prod-ucts include liquids, mastics, tapes, gaskets, heat-activatedmaterial, and mastic with an embedded fabric.seam: a connection of duct surface elements that is pr

33、imarilyoriented in the direction of airflow.sponsor: a manufacturer, trade association, or some othergroup that funds, sponsors, or requires ductwork tests in com-pliance with this standard.transverse joint: a joint that is used to assemble sections ofduct together or connect them to fittings.3.2 Sy

34、mbolsAf= final area, mm2Ai= initial area, mm2D = diameter, mmL = length, mmLrs= reinforcement spacing, mmLus= user-specified support spacing, mmPR = percent reduction, %Qa= leakage rate at actual conditions, L/sQs= leakage rate at standard air conditions, L/sANSI/ASHRAE/SMACNA Standard 126-2016 3R =

35、 gas constant, kJ/(kgK)W = duct width (flat surface), mmpb= barometric pressure, kPape= saturated vapor pressure of air, kPapp= partial vapor pressure of air, kPato= dry-bulb temperature, C= wet-bulb temperature, Co= density of atmospheric air, kg/m3s= density of standard air, kg/m3 = relative humid

36、ity, percentage4. INSTRUMENTATION4.1 Accuracy and Precision. Measurements from the instru-ments shall be traceable to primary or secondary standardscalibrated by the National Institute of Standards and Technol-ogy (NIST) or to the Bureau International des Poids etMesures (BIPM) if a National Metrolo

37、gy Institute (NMI)other than NIST is used. In either case, the indicated correc-tions shall be applied to meet the accuracy and precisionstated in this standard. Instruments shall be calibrated on aregular schedule that is appropriate for each instrument, but inno case less than annually. Calibratio

38、n records shall be main-tained. Instrument accuracy and precision shall be as follows:a. Temperature measurements shall be made using deviceswith an accuracy equal to or better than 1C and with aprecision equal to or better than 0.5C.b. Pressure shall be measured with an accuracy equal to orbetter t

39、han 1.0 Pa and a precision equal to or better than0.5 Pa.c. Barometric pressure shall be measured with accuracyequal to or better than 25 Pa.d. Flowmeters shall have an accuracy of 2% of reading.4.2 Temperature4.2.1 Temperature instruments and measurements shallcomply with ASHRAE Standards 41.11and

40、41.62.4.2.2 Calibration. Thermometers and temperature instru-ments shall be calibrated to traceable standards per Section 4.1.4.2.3 Wet-Bulb. The wet-bulb thermometer shall have a 3.5to 10 m/s air velocity over the water-moistened wick-coveredbulb or sensor. The dry-bulb thermometer shall be mounted

41、upstream of the wet-bulb thermometer so its reading will notbe depressed by the cooling effect of evaporated moisture.4.3 Pressure4.3.1 Pressure indicating-instruments shall comply withASHRAE Standard 41.33.4.3.2 Calibration. Each pressure instrument shall be cali-brated to traceable standards per S

42、ection 4.1.4.4 Barometers. Barometers shall be calibrated to traceablestandards per Section 4.1.4.5 Flowmeters. Flowmeter shall be an orifice or laminarflowmeter.4.6 Dial Indicators. Dial indicators shall have jewel bear-ings, a suitable range, and 0.01 mm graduations.5. TESTS5.1 Tests to be conduct

43、ed are listed below. At the discretionof the sponsor, a specific test specimen for more than one testis permitted.a. Leakageb. Deflection under pressurec. Deflection under superimposed loadsd. Impacte. Tensionf. Bendingg. Pressure cyclingh. Burst/collapsei. Puncturej. Temperaturek. HumidityInformati

44、ve Note: The purpose of each test is brieflyexplained in Informative Annex A.5.2 At the discretion of the sponsor, it is acceptable to omitindividual tests.5.3 When required by the sponsor, a leakage test shall beconducted before and after an individual test. Informative Note: If a specific test spe

45、cimen is to beused for a group of tests, a leakage test may be conductedbefore and after the test series. Exclusive leakage tests may beconducted on any specimen.6. LEAKAGE TESTThe leakage testing described below is intended to determinethe durability and air tightness of ducts and connections relat

46、edto the testing performed. This leakage test is not suitable todetermine the leakage class of a duct system.6.1 Test Specimen and Test Pressure. The duct assemblyand test pressure shall be specified by the sponsor. The endsof the duct assembly shall have sealed end caps.6.2 Test Setup6.2.1 The test

47、 setup shall be in conformance with Figure 1and Section 4. Informative Note: Example test setups are provided inInformative Annex B.6.2.2 Pressure shall be measured by an inclined manometeror other instrument in compliance with Section 4.3. The pres-sure connection shall be on the end cap opposite t

48、he supply/exhaust connection end cap.6.3 Test Procedure6.3.1 The end caps and instrument tubing shall be sealed.Resealing of end caps during any test is permitted providedthat the effects of the resealing are recorded.6.3.2 The test pressures shall be set at the levels specifiedby the sponsor.6.3.3

49、The duct pressure and leakage rate shall be recorded.6.4 Leakage Rate Correction 6.4.1 Leakage rates shall be corrected from actual condi-tions (Qa) to standard air conditions (Qs) by using Equation 1:to4 ANSI/ASHRAE/SMACNA Standard 126-2016Qs= Qa (a/s) (1)Informative Note: Refer to Informative Annex B, Sec-tion B2, for an example problem. For the example, the ductleakage rate at test and standard air density conditions are5.093 and 4.86 L/s, respectively.6.4.2 The density of atmospheric air (o) shall be deter-mined from measurements in the general test