Graphite electrode consumption rate & Eaf electrode connections
By:Yvonne Nov 23, 2020
Gross consumption of ton steel graphite electrode: MM = MZ / MG, So let DanCarbon talk about Graphite electrode consumption rate & Eaf electrode connections.
1. Graphite electrode consumption rate
The calculation of electrode consumption during the smelting process has two concepts, net consumption and gross consumption. Net consumption refers to the technical consumption of the technical water pump during the smelting process where the electrodes are sublimated, oxidized, and reacted. The sum lost without participating in smelting. At present, the iron and steel industry evaluates the physical quality of graphite electrodes by gross loss. graphite electrode consumption rate formula:
The first method: yield method
The production method is based on the amount of molten steel (finished product) produced in a certain period of time, and the consumption of graphite electrode input during the same period minus the remaining amount on the furnace.
Gross consumption of ton steel graphite electrode: MM = MZ / MG
Net consumption of ton steel graphite electrode: MJ = MC / MG
Among them: MZ is the total consumption of the electrode (input amount-remaining amount on the furnace), KG / T;
MC is the pure consumption of the electrode (input amount-remaining amount on the furnace-loss amount), KG / T;
MG is the finished product quantity of molten steel, T.
The second method: power consumption method
The power consumption method is based on the cumulative power consumption of the pure heating time in a certain period, and the graphite electrode input during the same period minus the remaining amount on the furnace is the consumption amount (the LF furnace calculates the power consumption and electrode every 1℃heating ).
Consumption of electrode per kWh:
MX = 1000 * MC / QH
Among them: MC is the pure consumption of the electrode (input amount-remaining amount on the furnace-loss), KG / T; QH is the cumulative power consumption in pure heating time, KW * H.
The output method basically uses gross consumption as the calculation method, and all use the output of the finished product as the calculation base. Although the power consumption method does not consider the loss other than the consumption of the smelting technology, it is still necessary to consider this loss in the assessment of the steel plant. This method will have a clear comparison between the batches of the electrodes.
In summary, the consumption evaluation of graphite electrodes in smelting at this stage is unfair. As the carbon industry, comprehensive evaluation methods should be actively recommended. That is, the industry should actively recommend the comprehensive evaluation method based on the output method. That is, the overall quality level and adaptability of graphite electrodes are evaluated by the output method; the electrode quality and furnace conditions are compared between the batches by the power consumption method; and other consumption during smelting must also be considered. In this way, both the supply and demand sides pay attention to the quality of the electrode, and also pay attention to the changes in the condition of the electric furnace, so as to achieve the purpose of promoting the best operation in the optimal use of the electrode.
2. Is there any gap while joining graphite electrode
When joining graphite electrodes
1) Firstly, blow the socket, end surfaces and nipples with compressed air. There must be no dust and the joints should be kept clean.
2) When the two electrodes are screwed in to a certain extent (about 10mm gap), blow it again with compressed air.
3) Then, tighten the electrode with a torque clamp and apply the torque when tightening. The gap between the both connection ends is not more than 0.05 mm;
4) If there is a gap at the joint after tightening, you must exit and re-join until there is no gap.
3. Eaf electrode connections
• Lift the new arc furnace electrodes over the old column, and slowly drop it vertically to avoid any thread damage occurring from shocks.
• Turn the new arc furnace electrodes with a torque ring. At this time, the lift plug and the electrode rotate down together until the end faces of the two electrodes contact.
• Tighten the electrode with appropriate torque to lock the electrode.
4.Use of arc furnace electrode
Electric arc furnace electrodes are mainly used in the Ac steelmaking arc furnace and Dc steelmaking arc furnace.