1、November 2014 English price group 6No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 23.040.80!%C%e“2320266www.din.de
2、DIN 28090-3Static gaskets for flange connections Gaskets made from sheets Part 3: Chemical resistance test procedures,English translation of DIN 28090-3:2014-11Statische Dichtungen fr Flanschverbindungen Dichtungen aus Dichtungsplatten Teil 3: Prfverfahren zur Ermittlung der chemischen Bestndigkeit,
3、Englische bersetzung von DIN 28090-3:2014-11Joints statiques dtanchit pour assemblages brides Joints dtanchit en plaques isolantes Partie 3: Mthode dessai pour la dtermination de la rsistance chimique,Traduction anglaise de DIN 28090-3:2014-11SupersedesDIN 280903:199509www.beuth.deDocument comprises
4、 8 pagesD02.16Translation by DIN-Sprachendienst. In case of doubt, the German-language original shall be considered authoritative. DIN 28090-3:2014-11 2 A comma is used as the decimal marker. Contents Page Foreword . 3 1 Scope 4 2 Normative references 4 3 General 5 4 Preliminary test . 5 5 Main test
5、 5 6 Test conditions . 7 7 Test report . 8 DIN 28090-3:2014-11 3 Foreword This document has been prepared by Working Committee NA 082-00-16 AA Flansche und ihre Verbindungen of the DIN-Normenausschuss Rohrleitungen und Dampfkesselanlagen (NARD) (DIN Standards Committee Piping and Boiler Plant). Atte
6、ntion is drawn to the possibility that some of the elements of this document may be the subject of patent rights. DIN shall not be held responsible for identifying any or all such patent rights. Amendments This standard differs from DIN 28090-3:1995-09 as follows: a) normative references have been u
7、pdated; b) requirements in Clause 7 have been deleted; c) the standard has been editorially revised. Previous editions DIN V 28090: 1989-01 DIN 28090-3: 1995-09 DIN 28090-3:2014-11 4 1 Scope This standard applies to the testing of sheet gasket materials as specified in DIN 28091-1 to DIN 28091-4 and
8、 the gaskets produced from such materials. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of t
9、he referenced document (including any amendments) applies. DIN 28090-2, Static gaskets for flange connections Gaskets made from sheets Part 2: Special test procedures for quality assurance DIN 28091-1, Technical delivery conditions for gasket sheets Part 1: General requirements for gasket materials
10、DIN 28091-2, Technical delivery conditions for gasket sheets Part 2: Requirements and testing for fibre-based gasket materials (FA) DIN 28091-3, Technical delivery conditions for gasket sheets Part 3: Requirements and testing for PTFE-based gasket materials (TF) DIN 28091-4, Technical delivery condi
11、tions for gasket sheets Part 4: Requirements and testing for expanded graphite-based gasket materials (GR) DIN EN 1092-1, Flanges and their joints Circular flanges for pipes, valves, fittings and accessories, PN designated Part 1: Steel flanges DIN EN 1514-1, Flanges and their joints Dimensions of g
12、askets for PN-designated flanges Part 1: Non-metallic flat gaskets with or without inserts DIN EN ISO 175, Plastics Methods of test for the determination of the effects of immersion in liquid chemicals DIN EN ISO 178, Plastics Determination of flexural properties DIN EN ISO 4014, Hexagon head bolts
13、Product grades A and B DIN EN ISO 4032, Hexagon regular nuts (style 1) Product grades A and B SEW 4001)Rolled and forged stainless steels 1) Obtainable from: Verlag Stahleisen mbH, Postfach 10 51 64, 40042 Dsseldorf DIN 28090-3:2014-11 5 3 General The purpose of this standard is to specify a test me
14、thod for determining the effects of chemicals on the mechanical properties (e.g. creep/relaxation behaviour) and leakage behaviour of sheet gasket materials. 4 Preliminary test The preliminary test is carried out on immersed specimens along the lines of DIN EN ISO 175 and only gives results that can
15、 be used for a rough estimate. This test should not be regarded as a substitute for the main test described in Clause 5, and mainly serves to exclude materials which are clearly unsuitable. The test vessel used shall be made of corrosion-resistant material and shall be leaktight. The specimens shall
16、 be either strips cut to dimensions specified in DIN EN ISO 178, or gasket sheet 42 mm 22 mm 2 mm in size. Prior to testing, subject the specimens to a compressive load of 30 MPa for at least 10 min. Take care that the specimens are completely immersed and fully exposed on all sides to the test medi
17、um. Immerse at least five specimens in one test vessel at a time. The ratio of the test medium volume to the total gasket surface area should be 4 cm3/cm2. After 24 hours at test temperature, cool the test vessel to room temperature, take out the specimens and visually examine them. Depending on the
18、 condition of the specimens, further tests (such as the three-point loading test described in DIN EN ISO 178) can be carried out. The results obtained can be evaluated by comparison with a reference specimen which has not undergone testing, taken from the same sheet. 5 Main test Determine chemical r
19、esistance using a flanged test assembly as shown in Figure 1, in a test apparatus made of a corrosion-resistant material, preferably steel of material number 1.4539 as specified in SEW 400. Four calibrated micrometers, each with a welded-on pin, shall be used to hold the flanges together (see Figure
20、 1). Before they are welded on, make sure the pins can move freely with as little friction as possible. Calibrate the micrometer/nut/washer system with a grip length of 41 mm. The level of friction shall be the same for calibration and for testing. Grease the micrometer thread and the nut faces with
21、 a non-volatile, temperature-resistant lubricant. Volatile matter in the lubricant can falsify results. Specimens shall be gasket sheets as in DIN EN 1514-1, DN 40, PN 40, with a thickness of preferably 2 mm. Condition the specimens in accordance with DIN 28090-2. Pour the test medium ( 20 ml) into
22、the bottom part of the test assembly. Four dial gauges are needed. Centre the gasket between the flanges and apply a compressive load of 30 MPa. Any deviations from this load due to the type of gasket material used shall be stated. Increase the load in four equal steps to 25 %, 50 %, 75 % and 100 %
23、by a crosswise tightening of the micrometers. This tightening procedure shall last no longer than 15 min. After 10 min, check the preload and correct if necessary. Remove the dial gauges needed to determine the elongation of the micrometer and weigh the test assembly using a scale with a limit of er
24、ror no greater than 0,1 g. Turn the test assembly upside down to expose the gasket to the test medium. Place the assembly in an oven and condition it at the given test temperature. After periods of 24, 100, 500 and 1 000 h each, cool the test assembly to room temperature and weigh it to determine th
25、e loss in test medium. DIN 28090-3:2014-11 6 Key 1 Precision dial gauge, with 0,001 mm scale intervals 2 Adaptor 3 M16 hexagon nut, property class A2-70, as in DIN EN ISO 4032 4 Washer 5 Blind flange DN 40, PN 40 as in DIN EN 1092-1, type A 6 Calibrated micrometer of size M16 70, property class A2-7
26、0 as in DIN EN ISO 4014, with a central bore of 3,20+0,1 mm 7 Weld neck flange DN 40, PN 40, as in DIN EN 1092-1 8 Base 9 Pin of diameter 3,0-0,10 mm 10 Specimen with dimensions 92 mm 49 mm gasket thickness, in mm, as in DIN EN 1514-1 Figure 1 Example of a test assembly DIN 28090-3:2014-11 7 Next, d
27、etermine the loss in micrometer force, by checking the change in length of all calibrated micrometers as described below: Place the dial gauge on the micrometer using an adaptor and set the dial indicator to zero. Then, loosen the hexagon nut, read the dial, and immediately tighten the nut until the
28、 dial indicator reads zero again. The loosening and re-tightening of the micrometer is to last no longer than 5 s. Determine the individual values for each micrometer. Determine the mean of individual values. State the mean value and the scatter of results. The measurement of the change in micromete
29、r length using the dial gauges shall be performed in such a manner that the plunger of the dial gauge is centrally (and vertically) inserted into the adaptor. 6 Test conditions The test medium and test temperature shall be selected to reflect actual service conditions. The tolerance for the test tem
30、perature is 5 K. Testing using the test conditions in Table 1 is sufficient for gaining a rough idea. Table 1 Test conditions Medium Test temperature Test duration C h Sodium hydroxide 30 % (mass fraction) 100 24 100 500 1000 Sulfuric acid 50 % (mass fraction) 40 Nitric acid 65 % (mass fraction) 40
31、Acetone 40 Toluene 100 Trichlorethylene 40 Deonized water 230 Air 40 Air 100 Air 230 DIN 28090-3:2014-11 8 7 Test report The test report shall include the following information: a) a reference to this standard; b) type, standard designation, and form of supply of tested material; c) manufacturer, ga
32、sket designation, batch number and date of manufacture; d) shape and dimensions of specimens before and after testing; e) specimen conditioning; f) any deviations from the test conditions specified in this standard as agreed with the client; g) test medium: quantity, designation and concentration; h
33、) test temperature; i) test duration; j) drop in micrometer force, or compressive stress of gasket material; k) any loss in volume of test medium due to leakage; l) visible external changes to specimens after testing (e.g. cracking, delamination, blistering or deformation); m) name of tester; n) date of test; o) name of laboratory or test body. Test reports shall only be published in an unabridged form.
