ISO 3580:2010 pdf free download – Welding consumables一Covered electrodes for manual metal arc welding of creep-resisting steels一Classification.
E.5 Covering type 15
Electrodes of this type have a covering that is highly basic, consisting largely of lime (calcium oxide) and fluorspar (calcium fluoride). Arc stabilization is provided mainly by sodium, and they are generally suitable for use on d.c. electrode positive only. They produce weld metal of high metallurgical quality with low diffusible hydrogen.
For purposes of determining compliance with the requirements of this International Standard, the actual test values obtained shall be subject to ISO 80000-1:2009, B.3, Rule A. If the measured values are obtained by equipment calibrated in units other than those of this International Standard, the measured values shall be converted to the units of this International Standard before rounding. If an arithmetic average value is to be compared to the requirements of this International Standard, rounding shall be done only after calculating the arithmetic average. If the test method cited in Clause 2 contains instructions for rounding that conflict with the instructions of this International Standard, the rounding-requirements of the test method standard shall apply. The rounded results shall fulfil the requirements of the appropriate table for the classification under test.
5 Mechanicaltests
5.1 General
Tensile and impact tests shall be carried out in the post-weld heat-treated condition specified in Table 2, using an all-weld metal test assembly type 1.3 in accordance with ISO 15792-1:2000 with 4,0 mm electrodes and welding conditions as described below in 5.2 and 5.3.
5.2 Preheating and interpass temperature
Preheating and interpass temperatures shall be selected for the appropriate type of weld metal as listed in Table 2.
The interpass temperature shall be measured using temperature indicator crayons, surface thermometers or thermocouples (see ISO 13916).
The interpass temperature shall not exceed the maximum temperature indicated in Table 2 when deposition of any pass begins. If, after any pass, the interpass temperature is exceeded, the test assembly shall be cooled in air to within the limits of the interpass temperature.
5.3 Pass sequence
The pass sequence shall be as indicated in Table 7.
The direction of welding to complete a pass shall not vary. Each pass shall be executed with a welding current of 70 % to 90 % of the maximum current recommended by the manufacturer. Regardless of the type of covering, welding shall be performed with a.c. when both a.c. and d.c. are recommended and with d.c. using the recommended polarity when only d.c. is recommended.
E.6 Covering type 16
Electrodes of this type have a covering that is highly basic, consisting largely of lime and fluorspar. Arc stabilization with potassium is responsible for their ability to weld with a.c. They produce weld metal of high metallurgical quality with low diffusible hydrogen.
E.7 Covering type 18
Electrodes of this type are similar to electrodes of covering type 16, except that they have a somewhat thicker covering with a metal powder addition. The metal powder increases their current-carrying capacity and deposition rate, as compared to electrodes of covering type 16.
E.8 Covering type 19
Electrodes of this type contain oxides of titanium and iron, usually combined in the form of the mineral ilmenite (iron titanium oxide). Although they are not low hydrogen basic electrodes, they are capable of producing weld metal of relatively high toughness.
E.9 Covering type 20
Electrodes of this type contain large amounts of iron oxide. The slag is very fluid, so that welding is generally suitable only in flat and horizontal positions. They are primarily designed for fillet and lap welds.
E.10 Covering type 27
Electrodes of this type are similar to electrodes of covering type 20, except that the covering is thicker and contains large amounts of iron powder in addition to the iron oxide of covering type 20. Electrodes of covering type 27 are primarily designed for high speed fillet and lap welds.