SNEL to put broken down machines back into service at the Inga dam- DRC
Since the end of September 2020, several subscribers of the national electricity company (SNEL) have experienced an increased problem in serving electric energy. For good reason, a deficit of at least 185 MW caused by the shutdown of two machines (G16 and G24) at the Inga dam (Kongo Central).
Group 4 of the Inga 2 (G24) plant produces a power of 130 MW, or nearly près of Kinshasa’s consumption. To remedy this situation, the 100% Congolese operating staff of SNEL has been hard at work day and night since the shutdown.
“It was a machine that was running. For the record, this machine has already more than 70,000 hours of operation. It happened that on September 28, we had significant leaks. ‘we usually have because there is always a schedule for the work on the various machines, it turned out that the situation worsened before the date scheduled for its maintenance. We had significant leaks, consequence we have our bearing which was polluted by water and therefore we could not continue to run the machine in this condition, ”explained Olivier Tshibangu, head of the ai division of the Inga 2 plant.
And to explain:
“Water is the operating principle of machines. Water attacks the turbine, the turbine turning drives the generator. At the level of the turbine, we manage to keep this water there in the turbine, c This is why there is a device to contain this water in the turbine. There are vane pots in which leaks have been observed which are due to the water which is charged, that is to say there is full of sand and with the movement of the guide vanes which allow the water to pass, that is to say to play on the flow, the wear has worsened “.
The number 1 of the Inga 2 plant, which notes significant progress in the work, believes that the end should come in early November.
“The machine itself can run but there will be a lot of water in the impeller which will prevent normal operation. We have 26 guide vanes and 26 vane pots that need to be dismantled, if you average the wear. , the presence of sand and corrosion you have one blade pot per day but SNEL made an effort by doubling the teams. We were able to dismantle everything in less than 15 days. We are at the cleaning stage, after We are starting to replace the defective linings. Unless something unexpected happens, we will pick it up the first week of November “, added Olivier Tshibangu.
At the Inga 1 power plant, it was the 6th group that experienced a short circuit of the exciter at the level of the alternator rotor on October 6. 55 MW of deficit which impacts the large entities of the district of Bas-Fleuve in Kongo Central (Matadi, Boma, Muanda, Tshela etc).
“It was since October 6 that the group 6 of the Inga 2 power plant experienced problems with its exciter. It was in fact a short circuit at the level of the connecting bars between the armature conductor and the soul of the collector. Group number 6 like all the other groups produce 55 MW, it is the equivalent of the service of the Lower River, from Matadi to Tshela via Kinzau-Mvuete, Boma and Moanda “, said Serge Mbiyavanga, head of division ai of the Inga 1 plant.
For this breakdown, the mechanical work of which is nearing completion, Mr. Mbiyavanga plans to put the group back into service at the end of October.
“The faulty part is already in the turn. We did not need the expatriates, it is the operator SNEL, that is to say the nationals who are already working. We are sufficiently advanced and within a few days the part will be completely revamped and could be reassembled for the resumption of operation of the machine by October 31 at the latest, “he said.
Commissioned in 1974, the Inga 1 power plant has 6 machines for a production of 351 MW. Inga 2, considered the largest of the power plants, was launched in 1982 with 8 machines (1400 MW). Only 6 machines are available, 3 of which are running. Apart from the G24, the G27 was already at a standstill long before to facilitate the finalization of the major works carried out by KCC at the G28.
