ABSTRACT:-The advantages of once through supercritical (OTSC) technology have become a focal point for increasing coal based thermal power generation sector in India. Indian Ultra Mega Power Projects (UMPPs), typically 4,000 MW each, were undertaken during the 11th five year plan and are slated to address increasing coal-based thermal power generation throughout the 12th and 13th five year plans. OTSC technology is expected to account for 40% of all coal-based thermal capacity additions during the upcoming 12th five year plan and all coal-based capacity additions for the 13th plan. These aggressive plans are set against a backdrop of fuel shortages as coal consumption has increased 6% while proven domestic reserves have increased only about 2.5%. The use of imported coals continues to address indigenous coal supply shortfalls. The Indian Central Electricity Authority (CEA) stipulated in 2011 that all future indigenous coal based thermal power plant boilers are to be designed for utilizat ion of fuel blend ratios of 30% imported coal/70% indigenous coal. Thus fuel flexibility will become an issue of incr easing importance in the adoption of OTSC technology in India.  The Roof panels in the second pass of OTSC boilers are designed with 540 openings to enable the ECO & LTRH hanger tubes to pass through the panels. This necessitates the introduction of 540 cut -out openings in the panel alternative tubes. This leads to 1560 additional Manual TIG joints  to fabricate these openings in the 13 roof panels. To eliminate Manual TIG joints in these roof panels, we had taken pre bended tubes, these pre bended tubes were aligned into straight line along with fins according to the drawing dimensions and then auto welding was carried out at pemamek panel formation machine. The welding and dimensions are found satisfactory. A cycle time reduction of 45 shifts per panel is achieved by this new method due to the elimination o f 1560 manual TIG joints (120 joints per panel).