1、Designation: F 2716 08Standard Practice forComparison of Nonmetallic Flat Gaskets in High PressureSaturated Steam1This standard is issued under the fixed designation F 2716; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice provides a means of comparing variousnonmetallic flat gasket materials, Classification F 104,insatur
3、ated steam service under controlled conditions. While thepractice is designed primarily for flat gaskets, it also can beapplied to various form-in-place gasket materials upon modi-fication. The practice may be used for quality control ormaterial comparison purposes as agreed upon between pro-ducer a
4、nd user. This practice is consistent with Fluid SealingAssociation test method, FSA-NMG-204-02, with regard tofixtures used and procedure.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided
5、 for information onlyand are not considered standard.1.3 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 and health practices and determine the applica-bility o
6、f regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A 193/A 193M Specification for Alloy-Steel and StainlessSteel Bolting Materials for High Temperature or HighPressure Service and Other Special Purpose ApplicationsA 194/A 194M Specification for Carbon and Alloy SteelNut
7、s for Bolts for High Pressure or High TemperatureService, or BothF 104 Classification System for Nonmetallic Gasket Mate-rials2.2 ASME Standards:3ASME B16.21 Nonmetallic Flat Gaskets for Pipe FlangesASME PCC-1 Guidelines for Pressure Boundary BoltedFlange Joint Assembly2.3 ESA/FSA Standards:4ESA/FSA
8、 Publication No. 009/98 Guidelines for Safe SealUsage - Flanges and GasketsFSA-NMG-204-02 Standard Test Method for Performanceof Non-Asbestos Gaskets in High Pressure, SaturatedSteam3. Significance and Use3.1 This practice may be used to evaluate ClassificationF 104 gasket materials using saturated
9、steam and standardASME RF (raised face) flanges. This practice is intended foruse as quality control or material comparison tool and shouldnot be used to predict performance.4. Apparatus4.1 The test equipment shall consist of the following com-ponents:4.1.1 Hot Air Circulating Oven, equipped with te
10、mperaturecontrols and capable of maintaining temperatures up to 570 65F (299 6 3C).4.1.2 Scales, capable of maintaining an accuracy of 60.1 gwith a nominal capacity of 12 kg.4.1.3 Flange FixtureA 2 in. cast steel Class 600 fixturemade from one weld neck flange capped by welding to boilercode and one
11、 blind flange (see Fig. 1). Flange surfaces are 275to 325 RMS in. (7.0 to 8.3 mm), flatness range 0.002 in.(0.05 mm). Each fixture shall have an identification number.4.1.4 Flange ProtectorsTo help ensure safe operation, usestandard metal flange protectors.4.1.5 Fasteners:4.1.5.1 Seven58-in. bolts,
12、4 in. long, per SpecificationA 193/A 193M, Grade B7.4.1.5.2 One calibrated bolt modified by the insertion of acalibration pin as detailed in Fig. 1.4.1.5.3 Eight58-in. hexagonal nuts per Specification A 194/A 194M, Grade 4, coarse thread.4.1.5.4 Sixteen58-in. hardened steel washers (38-45 HRC),Grade
13、 8.1This practice is under the jurisdiction ofASTM Committee F03 on Gaskets andis the direct responsibility of Subcommittee F03.10 on Composite Gaskets.Current edition approved May 1, 2008. Published May 2008.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Custom
14、er Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Three Park Ave., New York, NY 10016-5990, http:/www.asm
15、e.org.4Available from Fluid Sealing Association (FSA), 994 Old Eagle School Road,Suite 1019, Wayne, PA 190871866.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.1.6 Calibrated Dial Indicator, graduated to 0.0001 in.(0.0025 mm) and
16、equipped with a 90 conical contact point tobe used in conjunction with the adapter shown in Fig. 1.4.1.7 Torque WrenchOne calibrated torque wrench with aminimum capacity of 70 ftlbf (95 Nm).4.1.8 Torque WrenchOne calibrated torque wrench with arange of 0 to 200 in.lbf (0 to 23 Nm).4.1.9 Bolt Lubrica
17、ntHigh temperature-resistant molybde-num disulfide grease.4.2 Preparation of Apparatus:4.2.1 Prior to running any tests in a new fixture, the integrityof the assembled test fixture should be checked by running atest at a temperature at least 100F (38C) higher than the testtemperature, without exceed
18、ing the temperature/pressure ratingfor the flange. A standard gasket material approved for theseservice conditions shall be used with water as the test fluid.4.2.2 The maximum use temperature for the fixture withsaturated steam is 563F (295C). Therefore, if a test tempera-ture is not specified, this
19、 maximum shall be used as the default.However, any temperature that does not exceed this limit maybe used if agreed upon by the producer and user.4.2.3 Follow the steps in Section 9 for one cycle of aminimum of 24 h. Ensure that the gasket is acceptable for thattemperature/pressure.5. Test Specimen5
20、.1 The test specimen shall be a Class 600 2-in. (50-mm)ring gasket. It is recommended that a116-in. (1.5-mm) thickgasket be used. However, other thicknesses can be used ifagreed to by the producer and user.5.1.1 See ASME B16.21, Table 8, for gasket dimensions.5.1.2 See Classification F 104 for thick
21、ness tolerance.5.1.3 Preconditioning of the test gasket is not necessary,since this test is designed for shelf stock gaskets.6. Flange Limits6.1 Ensure that the test pressure never exceeds the pressure/temperature rating of the flange class:Class 600 Cast Steel 400F (205C) Limited to 1270 psig (88.6
22、 bar) or (8.87 MPa) 500F (260C) Limited to 1200 psig (83.8 bar) or (8.38 MPa) 600F (316C) Limited to 1095 psig (76.6 bar) or (7.66 MPa) 700F (371C) Limited to 1065 psig (74.5 bar) or (7.45 MPa)7. Test Limits7.1 Temperature/pressure properties for saturated steamfrom the steam table:FIG. 1 FSA Steam
23、Test FixtureF 2716 082400F (205C) Generates 235 psig (16.2 bar) or (1.62 MPa)450F (232C) Generates 405 psig (27.9 bar) or (2.79 MPa)500F (260C) Generates 665 psig (45.8 bar) or (4.58 MPa)540F (282C) Generates 945 psig (65.1 bar) or (6.51 MPa)550F (288C) Generates 1035 psig (71.3 bar) or (7.13 MPa)56
24、3F (295C) Generates 1145 psig (78.9 bar) or (7.89 MPa)8. Bolt Torque Guidelines8.1 The recommended assembly torque is 65 6 5 ftlbf (886 7 Nm), which produces a gasket stress of approximately 11000 psi (75.8 MPa). This calculation is based on the use ofmolybdenum disulfide grease as the bolt lubrican
25、t (4.1.9).8.2 A recommended article is “Torque - Tensioning Part II”by Dr. H. E. Trucks.5Also see ASME PCC-1.8.3 Various assembly torques may be used, as agreed uponby producer and user, and provided the gasket stress is neverless than 4350 psi (30 MPa).9. Procedure9.1 A minimum of two test assembli
26、es is recommended pergasket type tested.9.2 Ensure that the flange assembly has been thoroughlycleaned and that the exposed surfaces of the flanges are free ofall residues from previous tests. Inspect for nicks, scratches, orserious defects. Recondition when required. (WarningIt isimportant to check
27、 the flanges to ensure that the surfacesremain within the correct roughness and flatness range.)9.3 Ensure that the bolts, nuts, and washers are not damagedand that the nut runs freely onto the bolt by hand.9.4 Cut standard ASME 2-in., Class 600 ring gaskets.9.5 Clean bolt threads, nuts, and washers
28、 with an organicsolvent. Then lubricate bolts, nuts, and washers. Do notlubricate the dial indicator adapter assembly or the part of thecalibrated bolt that it will contact, since the presence oflubricants on these components will adversely affect boltelongation readings. Do not coat gasket or flang
29、es with anykind of release material.9.6 Assemble the fixture as follows:9.6.1 Place the empty weld neck flange on the scale and tareit.9.6.2 Pour 125 mL of water in the flange, and record theexact weight of water (Ww).9.6.3 Tare the scale, center the gasket onto the raised face ofthe weld neck flang
30、e, and record gasket weight (Gw).9.6.4 Place the blind flange carefully on the weld neckflange, and install the bolts, washers, and nuts finger tight.9.6.5 Install the dial indicator assembly (dial indicatormounted on adapter) over the calibrated bolt with a calibratedtorque wrench set to 40 in.lbf
31、(4.6 Nm), and zero the dial.Lock the dial indicator in the zero position, then remove thedial indicator assembly carefully. Bolt stretch may also bemeasured externally using an ultrasonic bolt stretch gauge fora given bolt.9.6.6 Using a calibrated torque wrench, torque the boltaccording to the FSA r
32、ecommended cross pattern in 3 incre-ments of 20 6 5 ftlbf (27 6 7 Nm) and finally one cycle at65 6 5 ftlbf (886 7 Nm) (see ESA/FSA Publication No.009/98 or ASME PCC-1, or both). Then torque each boltconsecutively in a counterclockwise pattern at 65 ftlbf (88Nm), doing the first bolt a second time. T
33、he final torque maybe adjusted as agreed upon between producer and user, butmust be clearly stated in the report. The default torque settingshall be 65 ftlbf (88 Nm) unless otherwise agreed upon andspecified.9.6.7 Complete the tightening process in 15 min.9.6.8 Ten minutes after completing the tight
34、ening processdescribed in 9.6.6, torque again with the FSA cross pattern to65 ftlbf (88 Nm). Finally, tighten each bolt consecutively in acounterclockwise pattern to 65 ftlbf (88 Nm), doing the firstbolt a second time.9.6.9 Reinstall the dial indicator assembly over the cali-brated bolt using a cali
35、brated torque wrench set to 40 in.lbf(4.6 Nm). Take the reading and record this value as Lo.Remove the dial indicator assembly carefully. This readingmay also be taken using an external bolt stretch gauge asdescribed in 9.6.5.9.6.10 Install the flange protector, weigh the assembly, andrecord the wei
36、ght as Wt.9.6.10.1 A separate dial indicator assembly (dial indicatormounted on adapter) will be required for each calibrated boltused in the test.9.7 Place the test rigs in the oven, and raise the temperatureso the test temperature is reached no sooner than in 30 min.Ideally, a temperature rate-of-
37、rise of 1C/min is preferred.NOTE 1The test can be run with the steam in contact with the gasketby locating the fixture in the oven with the liquid chamber down (steamphase). Another option is to allow the gasket to be in contact with the testliquid by reversing the fixture so the liquid chamber will
38、 be up (wetphase).NOTE 2The weekly steam cycle in Fig. 2 consists of two cyclesallowing time for the technician to take all the measurements in a normal5-day working week.9.8 After the indicated time at the chosen temperature, cooldown the oven to room temperature no sooner than 30 min.Ideally, a co
39、ol down rate of 1C/min is preferred.9.9 Remove the test rig from the oven and weigh it. Recordthe weight as Wr.9.10 Repeat the steps in 9.7-9.9 for a minimum of 10 cyclesand 1000 h. Test hours will include the ramp-up time for thefixture and the time held at temperature but not the cool-downtime. If
40、 Fig. 2 is followed, a 7-week test will comprise 1064 h.NOTE 3Cycles can vary from 9.7-9.10, provided there is an agree-ment between testing parties. Note any change from the default schedulein the report.9.11 After the final cycle is completed, measure and recordthe weight of the fixture, install t
41、he dial indicator adapter asdescribed in 9.6, take the reading, and record as Lf. Thisreading may also be taken using an external bolt stretch gaugeas described in 9.6.5.9.12 Dismantle the fixture, and record any relevant obser-vations.5Trucks, Dr. H. E., “Torque-Tensioning Part II,” Fastener Techno
42、logy, Decem-ber 1987.F 2716 08310. Calculation10.1 Calculate water loss as follows:W%5Wt WrWw3 100 (1)where:W%= water loss in percent,Ww= initial water weight,Wt= initial total assembly weight, andWr= assembly weight after each cycle.NOTE 4Determine weight loss due to the gasket and the lubricant by
43、running a dry test for a few cycles. Use results to confirm what effect theyhave on precision of W%.10.2 Calculate bolt elongation as follows:L%5Lo LfLo3 100 (2)where:L%= bolt elongation loss in percent,Lo= initial bolt elongation, andLf= final bolt elongation.10.3 Calculate incremental leak rate as
44、 follows:li5 Wri 1 Wri!/Ti! (3)where:Wri1= the previous Wr measurement,Wri= the current Wr measurement,Ti = the time increment during which the weightchange (Wri1Wri) occurred, andli= the leak rate for the time increment during whichthe weight change (Wri1Wri) occurred.NOTE 5Typical units are weight
45、 per secondwhich is useful forcomparisons.11. Report11.1 Report the following information (the information onthe worksheet in Fig. 3 is also reported to support the testfinding):11.1.1 Gasket identification and thickness under “Productdescription.”11.1.2 Initial bolt torque in ftlbf and calculated g
46、asket stressin psi under “Comments.”11.1.3 Indicate wet or steam phase under “Condition (Wetor Steam).”11.1.4 Total number of cycles and total hours.11.1.5 Temperature of the oven.11.1.6 Weight loss at each cycle.11.1.7 Bolt elongation loss in percent.11.1.8 General observations under “Comments.”11.
47、1.9 Leak Rate at each cycle.12. Keywords12.1 bolt elongation; flange gasket; gasket; nonmetallic flatgaskets; saturated steam; steam testFIG. 2 Weekly Steam CycleF 2716 084FIG. 3 FSA Steam Test Status WorksheetF 2716 085ASTM International takes no position respecting the validity of any patent right
48、s asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any t
49、ime by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views know
