Does this Steel carry the Load??
Dear Colleagues, Dear Energy Professional;
After graduating from Middle East Technical University Mechanical Engineering Department in 1973, I started to work in Alpullu Sugar Factory in Thrace. During the summer period, the revision continued non stop. Motors / pumps/ turbines were removed, cleaned and replaced. Bearings were checked, rusted / worn equipment were renewed, and electronic control equipment were checked, cleaned, repaired, and renovated.
At that time, in the sugar beet supply channel of the sugar plant, sugar beet capacity was unable to possess the capacity to feed, so we were to construct higher / bigger/ wider sugar beet feeding chutes in steel construction to wash beets and to feed the plant during operation. Construction responsibility was given to senior superintendent of raw plant, 60 plus years old Mehmet Usta from nearby Pancarköy village of Alpullu county. He was making his own simple static calculations based on his past in-house company education and vast past experience, choosing the necessary steel profiles to his wish from the stock site, making the welding and building the structural steel channel, working feverishly. ”Strength of Materials” course was very new in my mind, since I've repeated the course and got the best grade in the senior year. So I myself separately calculated the necessary profiles to carry that buckling load. Mehmet Usta had put quite strong steel/ heavy construction. One morning, I showed my calculations and advised that he could have used smaller size range of profiles, in order to pass the same distance, and it would be cheaper. My master listened to me, looked at the calculations, and said without critising, "Engineer, your calculations are pretty good, but it is solid steel construction, and it should first convince my eyes, convince my mind that I need to. That should first give me confidence in,". I did not understand, and I asked further clarification, "Engineer, you see a weight, then you see a load, then you see an opening, you note at your steel designer what profile he used, you write into your head. In some other place, you see similar weight, volume, similar to the load, similar to the one you noted earlier, to a similar opening, but they do not fit into with the previous profile. That new profile should give you confidence based on your past experience. That is called engineering feeling against to any calculation errors.” I checked my calculations once again. I noticed that I forgot to add fatigue factors. When those factors were added, then my profiles were close to the Selected the profiles of Mehmet Usta. If you have sufficient data, you sit down and calculate, and double check the outcome based on your past experience, and you should trust your engineering feelings. All these past years, I saw enormous amount load/ weight/ volume in thermal power plants. I saw very large openings and large volumes suspended. These days when I look at the steel structures of new cheap thermal power plants designed by the Far East companies, sayings of MehmetUsta come to my mind. While this is the cold steel, the existing structure may carry the load, but how about in hot operation, which means when the coal inside the thermal power plant is burning in high temperature combustion, can the same steel profiles carry the hot load?? How does the steel behave? For a long operation period, how is the wear/tear ? Do they carry properly, what is up?? I ask owners’ project control managers at site, “That steel construction seems weak, did you check? Did you make calculations once again by yourself?” They respond, "The main contractor has guaranteed the steel structure and the overall operation performance, I do not need to check." Why do you trust the contractor? Why don’t you make your own calculation?? That dependence / submission is not correct. In the end, we all have the same “Strength of Materials” course for engineering graduation. This new steel structures do not come to me at all reliable. I do not have any information in my hand. But owners’ a site engineers have all information and they should have double check. That is deemed necessary for long and uninterrupted operation of the power plant. The Far East contractor company has only one purpose in mind. They try to be the cheapest, it is not important to operate long periods, spares/ redundancy are not important. The key issue is the cheapest price in the market. Investors also want the cheap property, so how does the financier give credit to that investment? Based on what risk factors?? How is that plant calculated? That is a mystery. We received an order from Bechtel company in 1998. We were to supply 4 each high steam output capacity USA licensed package steam boilers. We had similar local references in the past, but this was the first in overseas. Contract was signed in London, England. Our price was the cheapest compared to USA and European competitors. We had a new condition in our contract. Bechtel asked to send a senior experienced engineer to our head office in order to check all our design calculations, and inspect our plant fabrication, review our project schedule and in the end do the plant acceptance tests all at their own cost. He should have an office fully equipped with PC / fax /phone. It was not usual practice but we accepted in order to receive that order. We were not expecting them to do it. However to our surprise, upon contract signing, Bechtel sent a senior experienced British mechanical engineer, who is working and serving the industry as freelance, and he spent one full year with us in our head office on Bechtel's own expense. He made every design check, got clarifications, compliance with ASME norms, and reviewed our plant fabrication and witnessed our plant acceptance tests. We are talking about a project at about 10 million US Dollars, not billions of US Dollars as in huge thermal power plants. In a power plant you should make all necessary controls, and make all necessary design checked by your own staff. You should not be at the mercy of the vendor. I always remember the wording of MehmetUsta from Alpullucounty of PancarKoy village. That steel structure should convince my eyes, my mind first. When I see the new imported coal firing thermal power plants, I check them by myself if they give me confidence based on my past experience. Will they work? Can they operate long periods without wear and tear? Will they stand 30+ years?? I do not know, I need to make serious calculations. For a temporary acceptance period of 2-3 years, they may works, but after that I suspect. These steel structures do not give me confidence with their appearance. When I look at those new cheap projects, it feels like toys. The investor makes decision in selection, pays the cheapest, but is this worth that?? The Creditor/ the Financier, how they place the project finance, on what parameters?? Is this risk acceptable?? Or let me ask like this, Can the project finance carry the high burden of this high risk? In last Cancun Climate Change conference in December 2010 following the Copenhagen meeting, there is no concrete consensus on limitation of CO2 emissions of fossil firing thermal power plants to reduce use of coal. But we have latest developments early 2011. There is flood in Australian coal mines, railway accidents to halt South African coal transportation from mines to seaside export sea ports, there are interruptions in Russia and Colombia due to latest weather conditions. IN the end there is shortage in coal supply in the imported coal spot markets. Coal prices started to increase from 80 US Dollars per ton to 130+ US Dollars per ton for 6000 kcal/kg LHV high quality imported coal. Weather conditions can change; railways can be reconstructed but the flood in Australian coal mines and railway lines will not be cleared in the short run. With these increased prices of imported coal, how will those new imported coal firing thermal power plants operate? May God help them all, and give them wisdom when making investments, and more wisdom to Financiers who cover project finance to those shaky projects. Your comments are always welcome. With deepest regards Haluk Direskeneli, Ankara based Energy Analyst