STD919橡胶撕裂强度判定.docVIP

Best?mning av rivh?llfasthet hos gummi Determination of tear strength Rubber 橡胶撕裂强度判定 Provningsmetod Testing method Allm?nt General Denna standard ?verensst?mmer med SIS 162203 utg?va 2. This standard agrees with SIS 162203, issue 2. Rivh?llfastheten anges med den dragkraft som f?r en i det f?ljande n?rmare beskriven sk?rad provkropp med nominell bredd och nominell tjocklek att brista. Rivh?llfastheten anges i N/mm. Tear strength is represented by the pull required to tear a slitted test piece, as described in the following, of nominal width and nominal thickness. Tear strength is stated in N/mm. 1 Provningsutrustning 1 Test equipment 1.1 M?tdon f?r best?mning av provkroppens tjocklek, vilket har plana och parallella tryckplattor med ca 6mm diameter, ger ett m?ttryck = 20(5 kNm2 och ?r graderat i hundradels mm. 1.1 For determination of test piece thickness, a gauge which has flat and parallel pressure plates of approximately 6mm diameter and exerts a measuring pressure of 20(5 kN/m2 and has a dial indicator with 100mm increments. 1.2 M?tmikroskop f?r kontroll av den sk?rade provkroppens effektiva bredd. 1.2 Reading microscope for measurement of the effective width of the slitted test piece. 1.3 Dragprovningsmaskin med sj?lvl?sande backar, vars dragkraft ska kunna avl?sas med en noggrannhet av (1% och vars draghastighet ska vara konstant och inst?llbar p? 500mm per minut. 1.3 Tensile testing machine with self-locking jaws, the pull of which shall be indicated to an accuracy of (1% and the speed of which shall be constant and adjustable to 500mm per minute. 2 Provkropp 2 Test pieces 2.1 Provkropp stansas ur 2-3 mm tjockt material med stans vars kontur framg?r av figur 1 och tv?rsnitt av figur 2. 2.1 The test pieces are punched out of 2-3mm thick material by means of a punch, the shape of which is shown by Fig. 1 and the cross section of which by Fig. 2. 2.2 Provkropp f?r stansas ur f?rdig vara. Om materialet ?r tjockare ?n 3mm slipas det ner till en tjoc