The progress of revitalization of HPP Djerdap 1 (“Iron Gate 1”), New power unit “A-4” to be erected In January

, News Serbia Energy

In early December, a new  turbine runner from Russia was dispatched to Serbian HPP “Djerdap” –  The installation organized Saturdays and Sundays in two extended shifts;  Holidays time reduced

The long-awaited turbine equipment for the power unit A-4, the rehabilitation of which began on the 1st July 2011, was shipped from St. Petersburg, Russia, on the 4th of December and was to reach the HPP “Djerdap 1” by the end of the month. What we talk about is the turbine runner that includes the hub and blades with working mechanisms, that was completed and tested in the halls of “Silovye machines” in St. Petersburg.

After arriving to the HPP “Djerdap 1”, the runner is scheduled to be corrosion-protected, hydraulically tested and installed, and then lowered into the so-called construction shaft. Basically, the long awaited installation of turbine equipment will begin in January, marking a kick off of the first – erection phase of the unit rehabilitation process, which according to the plan was to be completed within 12 months.

– To compensate as much as possible for the lost time, it is planned to introduce two extended work shifts lasting 10 hours each and Saturdays and Sundays work, while the number of holiday days will be cut to the minimum – explains Mr. Ljubisa Jokić, the director of the country’s largest hydroelectric power plant, adding that the current activities include installation of the lower ring and corrosion protection of the direction apparatus blades. – Also the control tests are performed and preparations made for the assembling of the unit, which includes the formation of working teams and that – three plus one. They are committed through their extended hard work to shorten several months of delay on the rehabilitation of the unit A-4, attempting to complete the assembly by the 15th  May, so to make possible that the following day, which coincides with the jubilee day of HPP “Djerdap 1”, the new A-4 is synchronized with the grid of EPS.

Following the receiving the turbine hub assembly, together with blades and the working mechanisms, at the HPP “Djerdap 1”, a part of the dismantled equipment from the unit A-4 will be dispatched to Russia for rehabilitation and revitalization so to be later installed into the new A-5 unit, the revitalization of which is scheduled after the 1st June 2013.

– This equipment completed the first phase of rehabilitation one year ago, and has been waiting since for shipping to the production halls of “Silovye machines”, St. Petersburg, Russia, which is the holder and the quality guarantor in the revitalization project of HPP “Djerdap 1”. Once there, it should be completely revitalized and within a four to five months turned back to Serbia.

However, Mr Jokić points that the revitalization of A-5 will not begin until all the equipment reaches its destination, implying to the equipment being revitalized in the local factories, which should be dispatched to Russia at the end of the year, and to the new, currently manufactured equipment.

Now the focus is on the new turbine runner. The hub of this vital part for the A-5 is manufactured by Italians. The new blades with more efficient profiles that bring an increase of about 10 percent in electricity production, are manufactured in “Litostroj”, Ljubljana, while their assembly and testing will be performed by Russian specialists in St. Petersburg. We also learned from Ljubisa Jokic that the first Danube hydropower plants are well prepared for the winter season and ready for improved hydrology of the great river.

Also it was fully implemented a comprehensive program of planned / preventive maintenance of the equipment, that involved: two complete capital overhauls, maintenance,  inspection check of the new revitalized unit A-6 after 7,000 hours of work, a short overhaul of the ship leader and replacement of the old transformer-block No 3 with a newer and stronger one. In December, a new transformer-block was erected and put to wait on the so called panel siphon for a suitable moment to be replaced, because this procedure takes at least a month of work. All this has contributed to the positive production effects. With the considerably increased production, HPP “Djerdap” in November for the first time fulfilled monthly production plan in this extremely dry year, thus announcing the safe operation and maximum utilization of the increased Danube River inflow in the coming months.

Unlike its “big sister”, HPP “Djerdap 2″ has achieved remarkable product results this year, and on the 14th of December it completed an extensive program of scheduled and preventive maintenance of production and other ancillary equipment. By rational use of lower inflows of the Danube River, which works well with this plant by creating greater fall, the HPP “Djerdap 2”, one month ahead of the schedule realized the annual production plan by producing one billion and 386 million kWh of electricity, and stands good chances for making a 120 million kilowatt-hours surplus at the end of the year

Also in this plant, repair procedures and maintenance of power units were performed right on time and successfully, and the pace of modernization and unification of the equipment were kept. According to Zoran Kršenković, director of HPP “Djerdap 2”, the workers completed successfully, on time and schedule, general overhaul of four units (3,4,5 and 6), maintained another four units (1,8,9 and 10) and performed an extensive, six-month long overhaul of the ship leader. Moreover, in cooperation with experts from the Institute “Nikola Tesla” and the “Institute for Testing Materials” of Belgrade they completed reconstruction of Central Command, the switchgear  6.3 KV of the power station and the switchgear 0.4 kV of the power unit 1 and 2, repaired a crack on the A-5 shaft, and made a reinforcement at the transition radius. HPP “Djerdap 2” is entering the New Year 2013 with all the 10 units and total operational capacity of  270 ready to take full advantage of the available inflows of the Danube.

The same forecast applies to two other members of the company HPP “Djerdap”, “Vlasinske HPPs” and HPP “Pirot” that are the peak energy producers. These plants were considerably engaged during the summer months due to the power system needs, but did not fail to fully realize plans for planned and preventive maintenance, with major reconstructive procedures for the purpose of unification and modernization of equipment. This is especially true for “Vlasinske HPPs”, which before the year end fulfilled production plan for 2012, and welcomes the year 2013 with all aggregates, including PAP “Lisina” ready for production as required according to the needs of the system, i.e. order of dispatchers of EPS.

It is also expected that the HPP “Pirot” will have fulfilled its annual production plan, since at the beginning of December they had already produced 90 of the planned 99 million kWh of electricity, at which in the accumulation “Zavoj” there was enough water to produce additional 53 million kilowatts.

Source; Kwh