Power for Steel

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Steel is a build­ing mate­r­i­al that runs through our entire lives. Most steel­works have been around since indus­tri­al­iza­tion and their mate­r­i­al can be recy­cled with almost no loss. Steel is also essen­tial for the ener­gy transition—be it for the con­struc­tion of elec­tric motors or wind farms. But for its pro­duc­tion to meet the require­ments of the ener­gy tran­si­tion, it must become sus­tain­able. thyssenk­rupp oper­ates Europe’s largest steel­works near Duis­burg and is active­ly work­ing on the future sus­tain­abil­i­ty of its pro­duc­tion.

“This not only includes sourc­ing more and more elec­tric­i­ty from renew­able sources,” explains Fabi­an Mar­quardt, Engi­neer High Volt­age Tech­nol­o­gy and Grid Plan­ning, “thyssenk­rupp Steel is cur­rent­ly under­go­ing a trans­for­ma­tion towards CO2-free steel pro­duc­tion at our site in Duis­burg. This strat­e­gy also includes ensur­ing the longevi­ty of our own equip­ment by expand­ing pre­ven­tive main­te­nance in a tar­get­ed man­ner.”

TESSA® FLEETSCAN 2D is designed to help with this. Using this dig­i­tal con­sult­ing approach from MR, the spe­cial­ists first record a large amount of mea­sure­ment data from the oper­at­ing equip­ment and then eval­u­ate it. This cre­ates a detailed pic­ture of the con­di­tion of the assets in terms of two dimen­sions: the risk of fail­ure and life­time con­sump­tion. The fail­ure risk index is aimed at ser­vice man­agers and looks to the imme­di­ate future, while the ser­vice-life con­sump­tion index is aimed at asset man­agers and their bud­gets for long-term plan­ning deci­sions.

Togeth­er they serve to devel­op a main­te­nance strat­e­gy based on the con­di­tion of a fleet. Repeat­ed at inter­vals of one to three years, TESSA® FLEETSCAN 2D pro­vides an accu­rate pic­ture of the con­di­tion of the equip­ment, which can be seen at a glance using the asso­ci­at­ed soft­ware.

Since the eval­u­a­tion is only as good as the pre­vi­ous­ly mea­sured data, the MR spe­cial­ists nor­mal­ly col­lect this data them­selves at the customer’s premis­es. In Duis­burg, how­ev­er, they took a dif­fer­ent approach, explains Philipp Birgmeier, Tech­ni­cal Con­sul­tant in the Ser­vice depart­ment: “thyssenk­rupp has very well-trained spe­cial­ists and want­ed to read out the trans­former data them­selves. That’s why we held a two-day train­ing course on site which will enable the spe­cial­ists to inspect their equip­ment based on our spec­i­fi­ca­tions, and col­lect the data nec­es­sary for our sub­se­quent eval­u­a­tion.” Mar­quardt adds: “The pre­vi­ous assess­ment aspects such as oil analy­ses or elec­tri­cal mea­sure­ments are com­bined and sup­ple­ment­ed by the stan­dard­ized visu­al inspec­tion. In this way, we ensure that the bud­get is used in the right places and that new acqui­si­tions are ini­ti­at­ed in good time despite long deliv­ery times.”

LEARNING THE THEORY

In the train­ing, the thyssenk­rupp spe­cial­ists were first taught some the­o­ry. “On the first day, we explained the data col­lec­tion to them and my col­league Nina Mach­nikows­ki from Devel­op­ment sup­port­ed the par­tic­i­pants in installing and using the TESSA® FLEETSCAN 2D web appli­ca­tion,” says Birgmeier. Users can lat­er save the mea­sured data and asso­ci­at­ed doc­u­ments via the app and retrieve them at any time, as well as check the val­ues of the eval­u­a­tion car­ried out.

The next day was all about prac­tice: after repeat­ing the the­o­ry, the engi­neers and tech­ni­cians col­lect­ed the data on two trans­form­ers using ther­mal imag­ing cam­eras and the addi­tion­al exper­tise of the MR pro­fes­sion­als. Birgmeier explains: “This includ­ed learn­ing to read the ther­mal images which are non-con­tact, non-destruc­tive imag­ing in real time, so they can be tak­en dur­ing oper­a­tion and pro­vide great insight into the con­di­tion of the equip­ment if you know what to look out for.” The aim here is to cre­ate a stan­dard­ized eval­u­a­tion sys­tem.”

Trained in this way, thyssenk­rupp employ­ees were able to record and enter the rel­e­vant trans­former data them­selves over the fol­low­ing few weeks which was then sent to MR togeth­er with doc­u­ments from pre­vi­ous mea­sure­ments. “We then eval­u­ate every­thing and write a detailed inspec­tion report for each trans­former as well as a fleet report that assess­es the con­di­tion of all assets as a whole,” explains Birgmeier, who is very sat­is­fied with the pilot project. “We can well imag­ine estab­lish­ing this pro­ce­dure with oth­er cus­tomers. The train­ing has shown us that this type of know-how trans­fer works well.”

Mar­quardt agrees: “Our tech­ni­cians and main­te­nance staff were enthu­si­as­tic about the prac­ti­cal train­ing. The core objec­tive was to teach them how to use the tool to enable them to car­ry out visu­al inspec­tions, and it was very impor­tant to us that the tool was easy to use on the indi­vid­ual end devices. The test eval­u­a­tions car­ried out met all objec­tives, and all ques­tions that arose were answered imme­di­ate­ly.”

PRACTICAL IMPLEMENTATION

Once the reports are ready, tech­ni­cians can also view them in the app at any time. In addi­tion to show­ing the con­di­tions, they also con­tain clear and pri­or­i­tized rec­om­men­da­tions for main­te­nance and repair of the indi­vid­ual units. If TESSA® FLEETSCAN 2D is repeat­ed in a few years, this will make the fore­casts and rec­om­men­da­tions even more accu­rate.

But why is such a detailed review of oper­at­ing equip­ment so impor­tant? In Duis­burg, the steel­works fleet con­sists of a total of 68 medi­um-volt­age and high-volt­age trans­form­ers that sup­ply the plant and espe­cial­ly the smelter with ener­gy. Some of these trans­form­ers are already at an advanced age. How­ev­er, new pur­chas­es are cur­rent­ly quite dif­fi­cult because deliv­ery times for both new trans­form­ers and spe­cial com­po­nents are between two and four years, depend­ing on the mod­el, man­u­fac­tur­er and intend­ed pur­pose.

“A sud­den fail­ure means a high finan­cial risk, espe­cial­ly in indus­try,” explains Birgmeier. Due to the high pri­or­i­ty of the infra­struc­ture, it is com­mon prac­tice for net­work oper­a­tors to car­ry out metic­u­lous main­te­nance and keep reserve trans­form­ers ready so that the pow­er sup­ply is guar­an­teed at all times. In indus­try, how­ev­er, this is not pos­si­ble for all assets, and trans­form­ers are replaced only as required. In some coun­tries, there is a trend towards oper­at­ing trans­form­ers under high­er loads and replac­ing them in good time, but this no longer works giv­en the cur­rent deliv­ery times, and it is also not a par­tic­u­lar­ly sus­tain­able approach.

For the steel­works in Duis­burg, these long deliv­ery times mean going the extra mile in terms of main­te­nance and con­di­tion analy­sis and keep­ing a con­stant eye on the assets even dur­ing oper­a­tion. “The right sen­sor tech­nol­o­gy is also cru­cial for this,” says Mar­quardt “and this is where we rely on online hydro­gen detec­tion with the MSENSE® DGA2 sen­sors from MR which detect creep­ing increas­es in the hydro­gen con­tent in the oil at an ear­ly stage and help to avoid seri­ous faults in the trans­former. The aim is to enable the fault in the trans­former sta­tion to be repaired at short notice instead of suf­fer­ing a total loss. It was good that we received an ear­ly and com­pe­tent overview of the new TESSA® FLEETSCAN 2D and MSENSE® DGA2 sen­sor tech­nol­o­gy via long-stand­ing MR sales con­tact Wern­er Sam­met.”