SIRAJGANJ 4, 413 MW

SIRAJGANJ 4, 413 MW POWER PLANT

Another achievement of Avant
SIRAJGANJ POWER PLANT: A project of SEMBCORP NORTH-WEST POWER COMPANY LTD. 400 MW DUAL FUEL POWER PLANT at SIRAJGANJ, BANGLADESH.

Major Scope of Works:
Construction of Temporary Jetty:
The temporary landing jetty was constructed by driving 9 m long wooden poles in 3-lines and 2-lines having a deck area of 750 m2. The approach road connecting the jetty deck and shore was 97 mx9 m. The approach road was also constructed by 9 m & 7.4 m long driven wooden poles.The wooden poles in both jetty and approach road were further strengthened by horizontal wooden runners in 3 & 2 layers. All such structural members were rigidly fixed and secured with steel nuts & bolts. The wooden poles were treated with Creosote oil to have a long-lasting effect. In the mid pocket of the main jetty, 9 m long 65 numbers of wooden poles were again driven to provide cross tie and anchorage to the vertically driven wooden poles. Geo-Textile Blanket was laid throughout the inside periphery of both main jetty and approach road. To prevent leakage of sand grains of the fill materials.At this stage inside pocket of the main jetty and approach road was filled with sand, sand filled bags layer by layer. The top of the deck and approach road was built with 450 mm thick sand mix brick bets and compacted by 8-10 ton Tandem Smooth Drum Roller was done at every 150 mm thick layers.
Over the top layer of compact sand mix brick bets, 700x700x400 mm RCC blocks were laid to withstand the enormous combined ground pressure exerted by Heavy Cargo, Hydraulic Modular Axels, 90 Ton Crawler Crane and the Gantry. All the components and parameters of the construction of jetty and approach road were designed and supported by engineering calculation. Such design and calcu- lation was approved by the employer before construction. As required by the employer, the jetty deck and approach road had safe bearing capacity of 25 ton/m2.
To satisfy safety requirements, 3 nos. of Plate Bearing Test were conducted on the Jetty Deck according to British Standard (BS) 1377 Part 9 and American Society of Testing & Materials (ASTM) D1194. Load bearing capacity of the Jetty passed all such stringent tests and was fully qualified to serve the purpose. During unloading operation maximum load sustained by the jetty was nearly 900 tons and at a particular point of time the jetty performed safely. We were assigned to transport 3 Heavy Lift Cargos as well as general cargos for the construction of 413 MW Dual Fuel Combined Cycle Power Plant as follows: No. of GT weighing: 410 Ton
No. of GTG weighing: 330 ton
No. of Transformer weighing 210 ton

Unloading Operation:
Unloading of GT(410 M.Ton) and GTG (330 M.Ton):

On arrival of the Loaded Barge with GT, it was secured first with Jetty and other 4 more Mooring Posts.

GT Operation:
The 410 ton GT was first raised by Jacks to desired height on the Barge Deck and Heavy Steel I-Beams rested on wooden slippers were inserted in between the Barge Deck and GT bottom. Steel Rollers were also placed on top of the I-Beams. On placement of all the rigging equipment and tools, the GT was again rested on the attachments by releasing Ram of the Jacks. Now, by gradual pulling the Gt was moved forward towards the Jetty Deck.
One Modular Hydraulic Axle (total 27 nos. of Axels) having deck area sufficient to accommodate the GT was placed before such operation. The GT thus approached gradually to the Axles and lifting and placing on Axles was done by Gantry Crane. The GT was secured strongly by adequate lashing so that during travelling there is no dislocation of the GT. Then the loaded GT moved pulled by on 1000 HP TITAN Prime Mover towards the Plant area.

GTG Operation:
The GTG weighing 330 Tons was also moved from the Barge and placed on the Jetty Deck in the similar manner. The GTG was lifted and placed on the Axles in the same way and after securing by adequate lashing was transported to the Plant Site.

Loading of Transformers:
In this case one 1000 Ton capacity Gantry having self-weight of 90 ton was boarded on the Barge Deck. This gantry lifted the Transformers and to such a height so that I-Beams, Wooden Slippers and Rollers could be placed below the Transformers. By gradual pushing, the Transformer was rolled off to Jetty Deck where the Trail- er and Axles were waiting. A that stages, the Transformer was lifted by Jacking and were slowly rolled off to rest on the Deck of the Axles. The Transformer was secured strongly by adequate lashing so that during travel- ling there is no dislocation of the Transformers. Then the Axles and Prime Movers with loaded Axles moved towards the Plant area.

410 MT GT of Sirajganj-4 CCPP project being loaded onto the barge

410 MT GT, 310 MT GTG, 27 lines Modular Axles, 1000 HP Tractor & 90 MT Crawler crane on Sirajganj-4 Temporary Jetty

410 MT Gas Turbine being transported from Temporary Jetty to Sirajganj-4 Power Plant site