1、November 2014 English price group 5No 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%n“2320275www.din.de
2、DIN 28091-3Technical delivery conditions for gasket sheets Part 3: Requirements and testing for PTFEbased gasket materials (TF),English translation of DIN 28091-3:2014-11Technische Lieferbedingungen fr Dichtungsplatten Teil 3: Anforderungen und Prfung fr Dichtungswerkstoffe auf Basis von PTFE (TF),E
3、nglische bersetzung von DIN 28091-3:2014-11Spcifications techniques pour plaques isolantes Partie 3: Exigences et essais pour matriaux dtanchit base de PTFE (TF),Traduction anglaise de DIN 28091-3:2014-11SupersedesDIN 280913:199509www.beuth.deDocument comprises 6 pagesD02.16Translation by DIN-Sprach
4、endienst. In case of doubt, the German-language original shall be considered authoritative. DIN 28091-3:2014-11 2 A comma is used as the decimal marker. Contents Page Foreword . 3 1 Scope 4 2 Normative references 4 3 Requirements 4 4 Testing . 5 4.1 General 5 4.2 Cold compression set KSW, KSWk5 4.3
5、Compression set at elevated temperature WSW/T,WSWk/T5 4.4 Determination of leak rate . 5 5 Material . 5 5.1 Main components 5 5.2 Material designation system . 5 5.3 Designation to be used when ordering 6 DIN 28091-3:2014-11 3 Foreword This document (DIN 28091-3:2014) has been prepared by Working Co
6、mmittee NA 082-00-16 AA Flansche und ihre Verbindungen of the DIN-Normenausschuss Rohrleitungen und Dampfkesselanlagen (NARD) (DIN Standards Committee Piping and Boiler Plant). Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. DIN a
7、nd/or DKE shall not be held responsible for identifying any or all such patent rights. DIN 28091 consists of the following parts under the general title Technical delivery conditions for gasket sheets: Part 1: General requirements for gasket materials Part 2: Requirements and testing for fibre-based
8、 gasket materials (FA) Part 3: Requirements and testing for PTFE-based gasket materials (TF) Part 4: Requirements and testing for expanded graphite-based gasket materials (GR) Amendments This standard differs from DIN 28091-3:1995-09 as follows: a) normative references have been updated; b) short-te
9、rm test values in accordance with DIN 28090-2 have been added; c) non-relevant or incorrect properties and limit values have been deleted or corrected; d) the standard has been editorially revised. Previous editions DIN 28091-3: 1995-09 DIN 28091-3:2014-11 4 1 Scope This standard specifies requireme
10、nts and methods of testing for PTFE based gasket materials (TF). This standard, in conjunction with DIN 28091-1, applies to PTFE based gasket sheets (TF) and gaskets produced from such materials. Gaskets produced using other methods can also be tested according to this standard. 2 Normative referenc
11、es 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 the referenced document (including any amendments) applies. DIN
12、28090-2, Static gaskets for flange connections Gaskets made from sheets Part 2: Special test procedures for quality assurance DIN 28091-1:2014-11, Technical delivery conditions for gasket sheets Part 1: General requirements for gasket materials 3 Requirements Table 1 contains requirements for PTFE (
13、TF)-based gasket sheets. Table 1 Requirements Item No. Property Unit Requirements 3.1 Appearance of the surface The material shall be free of cracks, delamination, indentations, grooves or clusters. Its thickness shall not exceed the limit deviations given in Table 1 of DIN 28091-1:2014-11. Given th
14、e wide variety of possible defects, comparison with reference specimens may be agreed upon. 3.2 Density or mass per unit area as in DIN 28090-2 g/cm3or g/cm2 To be specified by the supplier. Tolerances 5 % 3.3 Cold compression set KSWas in DIN 28090-2 (long-term test) % 20 35 50 for expanded PTFEa3.
15、4 Cold compression set KSWkas in DIN 28090-2 (short-term test) % 20 35 50 for expanded PTFEa3.5 Recovery at ambient temperature KRWas in DIN 28090-2 % To be specified by the supplier 3.6 Compression set at elevated temperature WSW/Tas in DIN 28090-2 (long-term test) % 50 35 15 for expanded PTFEa3.7
16、Compression set at elevated temperature WSWk/Tas in DIN 28090-2 (short-term test) % To be specified by the supplier (optional) 3.8 Leak rate as in DIN 28090-2 mg/(s m) 2,0 0,1 aThe differing values given for expanded PTFE sheet materials are due to their difference in structure and thickness when co
17、mpressed. DIN 28091-3:2014-11 5 4 Testing 4.1 General The specimen sheet should be 2 mm thick. 4.2 Cold compression set KSW, KSWkChoose a preload that will result in a compressive stress of 1,0 MPa being reached. The main load FHKshall produce a compressive stress of 20 MPa. 4.3 Compression set at e
18、levated temperature WSW/T,WSWk/TThe test shall be carried out according to DIN 28090-2 at 150 C (long-term test) or respectively at 250 C (short-term test). The main load FHWshall produce a compressive stress of 20 MPa. 4.4 Determination of leak rate For the determination of leak rate , see DIN 2809
19、0-2. 5 Material 5.1 Main components PTFE (TF) gasket materials are based on PTFE (TF), with or without fillers. Gasket materials in accordance with this standard are to be designated according to 5.2. The material designations indicate the fillers that have a decisive impact on the technical propert
20、ies. 5.2 Material designation system The designation is based on the letter symbol TF (for PTFE), followed by the symbols given in Table 2. Table 2 Symbols Type of filler Symbol Type of insert Symbol No fillers used O No inserts used O Glass G Steel St Carbon C Nickel-chromium steel Cr Mineral M Nic
21、kel Ni Other Z Aluminium Al Other Z DIN 28091-3:2014-11 6 EXAMPLE For structuring a material designation: TF G C Cr According to Table 2, the symbols in this designation have the following meaning: TF gasket material; 2 type of filler (main component); 3 type of filler (secondary component); Cr type of insert. 5.3 Designation to be used when ordering EXAMPLE For structuring a material designation for ordering: Gasket sheets DIN 28091 Dimensions TF G C Cr Name of manufacturer Type
