The event that scientists of Vietnam AGRIMECO company were successful in manufacturing a hydraulic power cylinder system with 400-ton lifting capacity to open and close valves of stream of Son La hydroelectricity work flabbergasted domestic and foreign scientists.
Mr. Le Van An- Director General of Agriculture, Irrigation Manufacture and Electromechanis Corperation (AGRIMECO), Chief of KC.05.DA.12 project on “Perfecting the design and manufacturing technology of hydraulic power cylinder system used for opening and closing device of irrigation and hydroelectricity works” said that processing and manufacturing opening and closing device and valves system for four drains of stream of Son La hydroelectricity acidentally happened. Because of the awearnesss that the corporation of Le Van An has produced, designed and manufactured hydro…and irrigation engineering devices for man years, No.1 electricity construction Consultancy Company gave Mr.An the design of drain of stream system.
An unimaginable innocentativeness
Formerly, the principle of constructuring hydroelectricity and irrigation works was that a dam made from concrete and steel rod and a system of drain of stream had to be built. Because Son La hydroelectricity has a very great size, the dam made from concrete and steel rod is 60m high with four drains of stream of 400 tons for each, it is necessary to use a device of 400-ton lifting capacity to open and close these valves. These are…and …device which can not be manufactured internally. Further more, when the drains of stream made from concrete is completed, a road from the top of dam need to be emtanked to bring thousands of tons of devices to drains of stream to install. Besides, drain of stream is 60m higher than the ground, so that it is not only expensive (around VND60-70 billion) to embark but also wasteful in time to execute and after entirely transfering devices, the road will be diged to execute other articles.
After carefully studying the design, team of technical officers and Diretor General Le Van An found out solutions to the design of openning and closing valves and an effective execution without emtanking the road, earning state expenditures and shortening time of execution. The sollutions were that when pouring around 12m-high concrete compared to the ground, crane with loading capacity of 100 tons would be used to put valves of stream into positions. Regarding to device of lifting and lowering valves , insteading of using fours big hydraulic power cylinders on the bottom of drains of stream, he proposed to use a transferable... with lifting capacity of 400 tons on which a hydraulic power cylinder on the top of the dam was installed in order to close valves in turn.Lifting and lowering device was designed with 8 hyraulic cylinders, each cylinder had lifting capacity of 50 tons installed into 8 steel bars to lift valves. Therefore, the road of transfering devices wasting tens of VND billion did not need to be executed, helping to shorten time to execute this article.
28 days and nights and 1.400 tons of equipment for Son La hydroelectricity
As soon as the Prime Minister approved the proposed project, AGRIMECO’s Board of Leaders met difficulties: due to requirements of executing drains, equipment of valves had just installed to catch ...., time for manufactruing lifting and lowering device was only next 28 days. According to enginering experts, manufacturing a 4-valve device with many complexed details within 1 month was unimaginable. If we call on foreign investors, it took us nearly 18 months with expenditure of around USD115 billion. Basing on the rich experiences, AGRIMECO mobilised all skilled technical officers to work in 12 hours per day, successfully manufacturing ....moving on the railway of the top of drains to open and close each valve.
In stipulated time, the system of lifting and lowering valves was successfully installed in the work ... the flabbergast of appearing execution units.
It took only around 2-3 hours to lift and lower each valve. This success contributed an important part to decision on.the starting ceremony of constructuring Son La hydroelectricity according to the plan, as well as completely changed the progress thinking of constructuring hydroelectricity existing up to now. Le Van An-Chief of project said “in order to ensure progress and quality of device, AGRIMECO mobilised a campaign of working in the whole day for Son La. Addition to considerably high wage regime, the Corporation also gave reward of VND100 thousand per day to encourage wokers’ spirit. Moreover, the Corporation also had a special reward regime for workers whose innotativeness help to speed up the progress. However, the time when lifting and lowering device was operated made eyewitnesses anxious, because a small mistake also had a bad effect to the progress of executing the work. When valves were successfully lowered , happiness seemed ..., and Director General Le Van An himself felt he has never had such love of life like this before.
The success of project has proved domestic engineering can successfully manufacture hydraulic power cylinders for national economy.
(Resource: Science and Develpment Newspaper)