Photo by Ngoc Loan
Mr. Trinh Van Tuan – PCC1’s Chairman of Management Board cum President and CEO revealed that this is an advanced, modern and effective solution. The balloon will pull a lure rope of a diameter which is as small as a chopstick, slim and light, but bearing. This lure rope is connected with 4 lure cables, located on the pillars, then a machine is used for stringing the line. The biggest difficulty in implementing this solution is that the synchronous devices are rather cumbersome and difficult for transportation. Therefore, the contractors often use balloon for pulling the long sections of cable (normally over 3 km), but a double brake is used for the shorter one and regular pulling is applied.
The highest advantage of this technology is that the balloon is used to string the power lines through the areas of special topography such as big river, high mountains, populous cities with many buildings and houses. In case the traditional tension is used, it will be very difficult, time and labour required, but expensive, because compensation and site clearance is required. It is absolutely correct in the locations where there are many buildings, houses, trees, crops and protection forests. Apart from the push up of the construction progress, this solution makes a reduction of duration of power-cut for construction, and compensation for crops and trees is not required, creating a high socio-economic effectiveness.
Thanks to the synchronous brake, the implementation of line stringing by balloon is 3 – 4 times faster, because all 4 lines are pulled at the same time instead of 1 line as done in the past. Concretely, it took only 1 day for stringing 7km of the 500kV Xuan Loc – Ham Tan transmission line. Besides, stringing line by balloons will not make the power line scratched, because of no clash against trees, the invester does not have to patch the lines after the installation.
Ảnh: Ngọc Loan
According to Mr. Tuan, the balloons used by PCC1 are imported from China, but all the engine and hydraulic power system are manufactured by Germany. Up to now, a full set of balloon including the subordinate equipment has a total cost of over VND 40 billions. At present, some contractors planed to hire this set of balloon to deploy the power projects in coming time.
The 500kV Vinh Tan – Song May transmission line running through Binh Thuan, Dong Nai provinces has a total length of over 237km, evacuating power from Vinh Tan Thermal Power Centre (in Tuy Phong district, Binh Thuan province) to the 500kV Song May substation (in Dong Nai province) to connect to the national power grid. This is a very important project which was implemented according to the special mechanism approved by the Prime Minister. It contributes to reduce the power shortage in the South in coming time.
PCC1 is known as the 1st unit in Vietnam using balloon for stringing line for the ultra-high voltage transmission line. Previously, PCC1 used balloon for implementing the 220kV transmission line evacuated power from Nho Que hydropower plant (of Ha Giang province) to the 220kV Cao Bang substation, where the topography is difficult to access, with many rocky mountains. Besides, PCC1 have applied this tecchnology for implementing many other projects, including the 500kV Son La – Hiep Hoa transmission line, in section of line running over Ma river and section closed to the 500kV Hiep Hoa substation, the 220kV transmision line branch to the 500kV Hiep Hoa substation running over Cau river, where the line string is very difficult …