In early July we went to Liuzhou, Guangxi, where it had been summer in South China, with large tall banyan trees standing on the either side of roads, shading the sun and bringing about shady cool to the pedestrians in the summer.

The major overhaul project for no.1 PG5361P gas turbine in Liuzhou Xinhegang Power Company was carried on by the overhauling unit of Nanjing Nangang Power and Equipment Installation Co., Ltd., which was commenced on Jul. 14, 2014; under the common endeavors of the overall overhaul crew members from the Nanjing Nangang Power and Equipment Installation Company, and with the close assistance from related leaders and engineering technicians as well as the overhauling personnel taking part in the project from Liuzhou Xinhegang Power Co., Ltd., the overhauling project was successfully completed on Aug. 18, 2014. After overhaul and reinstallation for the turbine set, on Aug. 19, departmental adjusting and testing were executed, and in the process of departmental test running and overall turbine running, although there were defections emerged in the crank equipment of the turbine set and in electromagnetic clutch of the fuel pump, with the common endeavors from our overhaul unit and overhaul personnel from the power plant, the problems in departmental adjusting and testing process were solved in time. By now the turbine unit has run normally.

The main overhaul items completed in the overhauling project are as below:

1.Inspect fuel nozzles, and replace all fuel nozzles;
2.Inspect the combustion parts such as crossfire tubes, firing liners, transition parts etc., and replace with new crossfire tubes and firing liners;
3.Inspect compressor rotors and stators, and deal with the adjust gaskets on compressor stator root;
4.Check the turbine stage 1 and 2 rotors, and replace the anti-moving pin on the root of impaired stage 1 rotor;
5.Replace turbine stage 1 nozzles; inspect turbine stage 2 nozzles;
6.Check the stage 1 and 2 shrouds in turbine casing;
7.Mend the cracks in turbine exhaust frame, and replace fractured outer heat preservation board; mend the cracks in exhaust chamber;
8.Treat the cracks on frame walls and flexible seals after air discharging;
9.Draw rotors from the generator for inspection;
10.Overall clean generator rotor parts and stators;
11.Add and renovate oil and smoke suction piping in the turbine set, add the suction piping in lube tank and add the suction piping front and behind of the generator bearing housing;
12.Add a drain orifice beneath inlet bell mouth;
13.Clean inlet system;
14.Check the fuel forwarding system;
15.Check cooling seal air system;
16.Check and measure related clearance and angles of IGV, and compare the locally given IGV angle data with the data on MARK V controlling panel for calibration;
17.Renovate and replace the heat preservation inner board on the roof of exhaust chamber;
18.Treat related defections existing in turbine set operation;
19.Check all disposable elements;
20.Change path for related piping in turbine small chambers.

After the major overhaul, the turbine set performs normally in normal running.

During the period of processing the major overhaul, when turbine set departmental and overall test running were executed after completion of reinstalling shrouds, defections happened in cranking system, affecting normal running of the turbine set, and when overall test running was executed, the turbine set main fuel pump and electromagnetic clutch defected, which, though, were not the problem left behind by the overhaul, but in order to put the turbine set in operation as soon as possible, our overhaul personnel worried for the clients, analyzed and treated the problem with the power plant personnel, and tried fastest speed to solve it. Our actions were admired by the owner.

Oil and gas suction equipment newly added in the major overhaul

Corner of the major overhaul

Severe burned impair on stage 1 nozzles

Draw turbine rotors in the major overhaul