Services

Preventive Analysis of Electric Cables Chilled Water

Introduction

The W.RADY constantly always sought to answer in the best way its customers demonstrating commercial partnership and technical support to them.
Through this constant concern, it offers technical service preventive analysis of electric water-cooled cables in order to check the cable wear condition installed in EAF furnaces (arcing) or LF (pan) before the oven stop working out of the planned schedule.

Historic

Historically it was only visual analysis observing wear hose, thermal protective fabric and of Bumper to bumper (This analysis was performed by the technicians of steel plant themselves).

The evaluation of the cross section of cable wear could be accomplished by measuring the electrical resistance in direct current, but this process requires that one side of each cable is unplugged that long time-consuming oven stop and hand consumption work.

Preventive analysis

Given the difficulty of the above, it created the indirect evaluation, which is to examine the distribution of electrical current between the cables at the same stage in the average at the time of reading the data, whereas the distribution should be uniform yielding the following analysis:
Cable with relative driving above 110%, is more request from the average and remain in this condition can lead to diminished life. It does not mean that there is an overload on the cable with respect to its nominal capacity, but with the average of the cables of the same phase which data were collected simultaneously;
Cables with driving on the average between 80% and 110% are considered within the normal range, i.e. they are within the expected range (ideal);
Cables with driving on the average between 79% and 60% should be observed more frequently;

Cables with driving on the average less than 60% should be replaced at the first opportunity of shutdown;
Cables that are experiencing driving on the average equal to 0% should be replaced as soon as possible because they are completely broken.

Procedure

sensors will be placed (toroids) in each cable to be measured the electric current;
The oven should be connected to the reading of the data, but you must turn it to place and remove the sensors, the installation of the sensors should be performed after the last load of the oven and removed preferably before the leak of the race;
The analyzer (dedicated computer) will simultaneously collect the driving values of the electric current of each cable for about 30 seconds, preferably during refining when we have the greater stability of electric current;
After the execution of the items listed above, the sensors will be removed and will be completed data collection;

12 will be read or 6 cables simultaneously.