ASHRAE 41 4-2015 Standard Method for Measuring the Proportion of Lubricant in Liquid Refrigerant.pdf

1、ANSI/ASHRAE Standard 41.4-2015(Supersedes ANSI/ASHRAE Standard 41.4-1996)Standard Method forMeasuring theProportion of Lubricantin Liquid RefrigerantApproved by ASHRAE on April 30, 2015, and by the American National Standards Institute on May 1, 2015.ASHRAE Standards are scheduled to be updated on a

2、 five-year cycle; the date following the Standard number is the year ofASHRAE Board of Directors approval. The latest edition of an ASHRAE Standard may be purchased on the ASHRAE web-site (www.ashrae.org) or from ASHRAE Customer Service, 1791 Tullie Circle, NE, Atlanta, GA 30329-2305. E-mail:ordersa

3、shrae.org. Fax: 678-539-2129. Telephone: 404-636-8400 (worldwide) or toll free 1-800-527-4723 (for orders inUS and Canada). For reprint permission, go to www.ashrae.org/permissions. 2015 ASHRAE ISSN 1041-2336SPECIAL NOTEThis American National Standard (ANS) is a national voluntary consensus Standard

4、 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 interest categories. This signifies the c

5、oncurrence 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 jurisdiction makes compliance mandatory thr

6、ough 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. The ProjectCommittee Chair and Vice

7、-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 Manager of Standards of ASHRAE should

8、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 efforts to promulgate Standards and

9、 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 accordance with ASHRAEs Standards or G

10、uidelines 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 method of testing for rating purposes

11、, 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 for them, and conformanceto them i

12、s 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 41Cognizant TC: TC 1.2, Instruments and Measureme

13、ntSPLS Liaison: John F. DunlapMark Kedzierski, Chair* Alexander Leyderman*Richard L. Hall, Vice-Chair* Kevin Peck*James L. Douglas, 41.4 Subcommittee Chair*Michael Perevozchikov*Kevin L. Amende* John Scott*Erik S. Anderson* Frank J. Spevak*B. Terry Beck* Russell C. Tharp*Patrick E. Collins* Michael

14、A. Wegenka*Lloyd Le* * Denotes members of voting status when the document was approved for publicationDenotes members of Subcommittee 41.4ASHRAE STANDARDS COMMITTEE 20142015Richard L. Hall, Chair James W. Earley, Jr. Mark P. ModeraDouglass T. Reindl, Vice-Chair Steven J. Emmerich Cyrus H. NasseriJos

15、eph R. Anderson Patricia T. Graef Heather L. PlattJames Dale Aswegan Rita M. Harrold Peter SimmondsCharles S. Barnaby Adam W. Hinge Wayne H. Stoppelmoor, Jr.Donald M. Brundage Srinivas Katipamula Jack H. ZarourJohn A. Clark Debra H. Kennoy Julia A. Keen, BOD ExOWaller S. Clements Malcolm D. Knight B

16、jarne Wilkens Olesen, CODavid R. Conover Rick A. LarsonJohn F. Dunlap Arsen K. MelkovStephanie C. Reiniche, Senior Manager of Standards ASHRAE (www.ashrae.org). For personal use only. Additional reproduction, distribution, or transmission in either print or digital form is not permitted without ASHR

17、AEs prior written permission.CONTENTSANSI/ASHRAE Standard 41.4-2015,Standard Method for Measuring the Proportion of Lubricant in Liquid RefrigerantSECTION PAGEForeword .21 Purpose.22 Scope23 Definitions and Symbols24 Requirements25 Instruments .36 Equipment Required .37 Test Methods 38 Test Procedur

18、es59 Calculations.510 Uncertainty Calculations611 Test Reports612 Normative References.7Informative Annex A: Informative References and Bibliography.8Informative Annex B: Methods for Uncertainty9Informative Annex C: Guidance Regarding Lubricant Sampling Procedure .10Informative Annex D: An Uncertain

19、ty Analysis Example for Lubricant Circulation Rate 1%.11NOTEApproved addenda, errata, or interpretations for this standard can be downloaded free of charge from the ASHRAEWeb site at www.ashrae.org/technology. 2015 ASHRAE1791 Tullie Circle NE Atlanta, GA 30329 www.ashrae.org All rights reserved.ASHR

20、AE 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. ASHRAE (www.ashrae.org). For personal use only. Additional reproduction, distribution, or transmission in ei

21、ther print or digital form is not permitted without ASHRAEs prior written permission.2 ANSI/ASHRAE Standard 41.4-2015(This foreword 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 t

22、o the ANSI requirements for a standardand may contain material that has not been subject topublic review or a consensus process. Unresolved objec-tors on informative material are not offered the right toappeal at ASHRAE or ANSI.)FOREWORDASHRAE Standard 41.4 was last revised in 1996 (and reaf-firmed

23、in 2006), prior to the global commitment to use refrig-erants with lower global warming potential that require theuse of synthetic lubricants instead of mineral oils. The meth-ods used in this revision apply to all lubricant-refrigerantcombinations. This standard has been revised to comply withASHRA

24、Es mandatory language requirements and to moreclearly specify the test requirements and procedures.Safety is an important consideration for all proceduresinvolving refrigerantwear safety glasses and other personalprotection equipment.1. PURPOSEThis standard prescribes a method for measuring the prop

25、or-tion of lubricant in liquid refrigerant.2. SCOPE2.1 This standard uses the gravimetric method as the primarymethod, but alternative methods can be used if those methodsare calibrated against the primary method.2.2 This standard does not apply to collected samples thatcontain less than 0.001 g (0.

26、015 grains) of lubricant.3. DEFINITIONS AND SYMBOLS3.1 Definitionsaccuracy: the degree of conformity of an indicated value toan accepted standard value, or true value. The degree of inac-curacy is known as total measurement error and is the sum ofbias error and precision error.bias, fixed, or system

27、atic error: the difference between thetrue or actual value to be measured and the indicated valuefrom the measuring system that persists and is a characteristicof the particular instrument or measurement technique.error: the difference between the true value of the quantitymeasured and an observed v

28、alue. Because the true value is notknown, it is estimated by the mean. The difference betweenthe mean and an observed value is called its deviation.lubricant circulation rate on the refrigerant basis: the ratioof the mass of lubricant to the mass of refrigerant in the sam-ple.lubricant circulation r

29、ate on the sample basis: the ratio ofthe mass of lubricant to the mass of refrigerant and lubricantin the sample.mean: the sum of measurement values divided by the numberof measurements. Mean is considered the best approximationof the true value.packless all-metal diaphragm valves: valve manufacture

30、rs usethis term to describe diaphragm valves that have polytetrafluo-roethylene (PTFE) gaskets but have no elastomeric seals.precision: the closeness of agreement among repeated mea-surements of the same characteristic by the same methodunder the same conditions.random error (or precision error): a

31、statistical error that iscaused by chance and is not recurring. There are two types ofrandom error:additive errors: errors that are independent of the magni-tude of the observations.multiplicative errors: errors that are dependent on themagnitude of the observations.resolution: the minimum observabl

32、e difference between twovalues of a measured characteristic.uncertainty: a measure of the potential error in a measure-ment or experimental result that reflects the lack of confi-dence in the result to a specified level.3.2 Symbols, SI (I-P)M1= mass of an empty cylinder assembly, g (grains)M2= mass

33、of a cylinder assembly plus the mass of therefrigerant-lubricant sample, g (grains)M3= mass of a cylinder assembly plus the lubricant in thesample, g (grains)M4= mass of an empty beaker, g (grains)M5= mass of a beaker plus the lubricant in the sample, g(grains)CR= ratioofthemassoflubricanttothemasso

34、frefrigerantin the sample, dimensionlessCS= ratioofthemassoflubricanttothemassofrefrigerantand lubricant in the sample, dimensionless= meanoftheindependentobservationsofthelubricantcirculation rates (CRor CS), dimensionlessn = number of independent observations of lubricantcirculation rates, dimensi

35、onless4. REQUIREMENTS4.1 Test Plan. A test plan is a document or other form ofcommunication that specifies the tests to be performed andthe required measurement accuracy for each test. Sources ofthe test plan include, but are not limited to, (a) the person orthe organization that authorized the test

36、s to be performed, (b)a method-of-test standard, (c) a rating standard, or (d) a regu-lation or code.4.2 Values to Be Determined4.2.1 The mean of the lubricant circulation rate on the sam-ple basis (percent).4.2.2 The lubricant circulation rate on the sample basis(percent) expressed as the mean plus

37、 or minus three times thestandard deviation of the mean (SDM) if specified in the testplan.4.2.3 Measurement uncertainty, unless otherwise specifiedin the test plan.C ASHRAE (www.ashrae.org). For personal use only. Additional reproduction, distribution, or transmission in either print or digital for

38、m is not permitted without ASHRAEs prior written permission.ANSI/ASHRAE Standard 41.4-2015 35. INSTRUMENTS5.1 Instruments and data acquisition systems shall beselected to meet the accuracy limits specified in the test plan.5.2 Measurements from the instruments shall be traceable toprimary or seconda

39、ry standards calibrated by the NationalInstitute of Standards and Technology (NIST) or to the BureauInternational des Poids et Mesures (BIPM) if a NationalMetrology Institute (NMI) other than NIST is used. In eithercase, the indicated corrections shall be applied to meet therequired uncertainty stat

40、ed in subsequent sections. Instrumentsshall be recalibrated on a regular schedule that is appropriatefor each instrument, and calibration records shall be main-tained. All instruments shall be applied in a manner thatensures compliance with the accuracy specified in the test plan.6. EQUIPMENT REQUIR

41、ED6.1 Analytical Scale. Determine the estimated lubricantmass in a sample using Table 1. The selected analytical scaleshall have a resolution that is equal to or greater than the min-imum resolution calculated using Equation 1, and shall havean operating range that is capable of weighing the cylinde

42、rassembly filled with a sample:(1)6.2 Cylinder Assembly. Figure 1 shows a schematic thatidentifies the components of the cylinder assembly and showsthe cylinder assembly connected to the refrigerant liquid lineaccess port during sampling. Select a cylinder that meets eachof the requirements stated i

43、n Section 6.2.1 through 6.2.6.6.2.1 Cylinder Internal Volume. The maximum cylinderassembly internal volume is 50 mL (0.013 gal) for refrigerantsystem capacities less than 70.4 kW (20 tons), and 500 mL(0.13 gal) for system capacities greater than or equal to 70.4kW (20 tons). Determine the required m

44、inimum internal vol-ume of the cylinder by following Steps 6.2.1(a) through6.2.1(g).a. Use Table 1 to estimate the lubricant sample mass.b. Divide the estimated lubricant sample mass (Step 6.2.1a)by the expected lubricant circulation rate to obtain the cor-responding estimated mass of refrigerant.c.

45、 Obtain the density of the saturated liquid refrigerant at25C (77F) from REFPROP,1or from the refrigerant sup-plier if the refrigerant is not included in REFPROP.d. Divide the estimated mass of refrigerant (Step 6.2.1b) bythe liquid refrigerant density (Step 6.2.1c) and by 0.8 toobtain a minimum cyl

46、inder assembly internal volume.e. Calculate the internal volume of the tubing and valves thatare an integral part of the cylinder assembly (see Figure 1).f. Subtract out the internal volume of the tubing and valves(Step 6.2.1e) from the minimum cylinder assemblyinternal volume (Step 6.2.1d) to obtai

47、n the minimumcylinder internal volume.g. Select a cylinder that has an internal volume greater thanthe minimum cylinder internal volume (Step 6.2.1f).6.2.2 Cylinder Assembly Components. Figure 1 shows aschematic of a cylinder assembly. The cylinder assembly shallinclude a pressure relief valve or ru

48、pture disc (described inSection 6.2.5), three diaphragm valves, tube fittings, and con-necting tubing. The diaphragm valves shall be manually oper-ated all-metal packless diaphragm valves. Diaphragm valvesof this type are commercially available with pressure ratingsup to 241 bar (3500 psig).6.2.3 Cy

49、linder Assembly Materials. All cylinder assem-bly materials shall be corrosion resistant, chemically compat-ible, and pressure-rated in accordance with Section 6.2.4.6.2.4 Cylinder Assembly Pressure Rating. The entire cyl-inder assembly shall have a working pressure no less than therefrigerant saturation pressure at 85C (185F), or two timesthe maximum refrigerant system operating pressure, which-ever is greater, in accordance with UL 207.26.2.5 Cylinder Assembly Pressure Relief. The cylinderassembly shall incorporate a relief valve or a rupture d