IEC 60779:2020 pdf download – Installations for electroheating and electromagnetic processing – Test methods for electroslag remelting furnaces.
3.3.1 08 secondary electrical circuit of an electroslag remelting furnace electrical circuit which is closed by the melting power supply and may include a) output terminals of melting power supply; b) high-current feeder (busbars and/or cables); c) bus switches, if required; d) electrode clamp; e) electrode stub; f) consumable electrode or electrodes (depending on the connection system); g) conductive molten slag (not included in the short-circuit test); h) remelted ingot (not included in the case of the furnace with more than two electrodes); i) base plate (depending on the connection system) 3.3.1 09 electrode clamp metallic, water-cooled equipment for holding an electrode and supplying the current to the electrode 3.3.1 10 coaxial arrangement of the electroslag remelting furnace arrangement of more than two return conductors symmetrically positioned around the crucible for the electroslag remelting furnace 4 Basic provisions for testing and test conditions Clause 4 of IEC 60398:201 5 is applicable. 5 Comparing equipment or installations Clause 5 of IEC 60398:201 5 is applicable. 6 Measurements and workloads Clause 6 of IEC 60398:201 5 is applicable except as follows. 6.4.3 Measurement positions Addition: For measurement positions of all electrical parameters of the power circuit of electroslag remelting equipment, see Figure AA.1 -Figure AA.3, being at output terminals of supply disconnecting device for the electric consumption measurement of the power circuit, and at the output terminals of the power distribution cabinet in shop for other electrical and mechanical auxiliaries (see 4.3 of IEC 60398:201 5). 7 Numerical modelling Clause 7 of IEC 60398:201 5 is applicable.
8 Technical tests Clause 8 of IEC 60398:201 5 is applicable except as follows. Additions: 8.1 00 Measurement of the effective stroke of the electrode ram motion The effective stroke of the electrode ram motion is the distance between the upper limited position and the lower limited position of the electrode ram where the motion stops. The measurement shall be made with a meter ruler when the main power of the furnace is off. 8.1 01 Measurement of the speed of the electrode motion The measurement shall be made with manual control of the moving system of the electrode in two directions under the condition that the furnace is equipped with the electrode(s) of the largest weight and length allowed by the designer. NOTE The measurement can be made by another method, for example, using electric signal control. The measurement of the speed of motion shall be carried out by means of a stop-watch (or electronic time-base control), noting the distance covered by the electrode arm relative to its fixed support. 8.1 02 Measurement of the time interval for exchanging electrodes The purpose of this test is to check if the time interval for exchanging electrodes meets the requirements agreed between the manufacturer and the user when the furnace is equipped with two sets of electrode feed drive systems.
The time to be measured with a stop-watch is the time interval from the moment when the secondary current becomes zero after the first electrode has melted and pulled out of the molten slag to the moment when the next electrode is dipped into the slag pool and the secondary current flows in the circuit. 8.1 03 Measurement of the open-circuit secondary voltage of the electroheating installation This test shall be carried out across the melting power supply terminals (see item 6 in Figure AA.1 ). If the installation is provided with a regulation system, the minimum and the maximum open- circuit secondary voltages shall be measured. 8.1 04 Measurement of the electrical parameters of the secondary circuit of the electroheating installation 8.1 04.1 General The purpose of this test is to check if the characteristics of the secondary circuit of the furnace meet the requirements agreed between the manufacturer and the user.