Reconditioning of electric equipment of rolling mill “1800”.
Owing to the fire that happened on the 15th of May, 2016 in several electrical rooms of rolling mill “1800”, the following equipment went out of order and therefore required the replacement: electric equipment of screw-down mechanisms and coiler after stand, electric equipment of control desks of pumps and coolant management system damper valves and electric equipment of integrated cable system as well.
Brief description of basic mill drives:
- Mill stand drive — double-anchor motor 2 х 4,5 MW, 900 V, 5000 A, 12-pulse rectification circuit.
- Coiler drive — three motors for 1,5 MW, 750 V, 2000 A, united by one reduction gear unit. The coilers before and after stand are similar.
- Screw-down mechanisms drive — two motors for 165 kW, 440 V, 500 A.
The last large-scale reconstruction took place in 2001 and was conducted by our company as well. It involved withdrawal from operation of valve inverters produced in remote 1960s and their subsequent replacement by “ABB” converters. The mill stand drive was implemented on basis of 4 complete DCS converters for 5000 A; coiler drives were implemented on basis of DCR-controlled old gate units. All other drives were implemented on basis of complete DCS converters, while mill operation was executed on basis of Advant controller (“ABB”).
The gate units of “ASC” design and manufacture controlled by Sinamics DCM modules were used to recondition the coiler drive. Upon customer’s request the same equipment was used for the coiler before stand that was not destroyed by the fire (6 converters in total). Screwdown mechanisms drives were reconditioned on basis of complete Sinamics DCM modules. The fact that Advant net periphery was partially destroyed too resulted in replacement of master controller for Simatic S7- 400 controller.
The electrical installation works were executed by “UralPromEnergo” company. They lasted for one month. It took two weeks to perform the commissioning.
The 5th of December, 2016 became the day when the first coil was produced on the mill.