The scope of work for the project included removal and reinstallation of conductors, conductor insulator assemblies, overhead ground wires, and overhead ground wire assemblies on the Tracy-Los Banos transmission line between the 500-kV approach tower and 500-kV take-off structure type II. All of this work was required to replace and or repair the structural steel members of the take off structure and approach tower.
The existing beam on the 500-kV take-off structure type II was removed and replaced with a Government-furnished repair beam. The existing column leg weld defects were repaired and Government-furnished gusset plates were welded to the take off structure as well as the approach tower to ensure structural integrity.
Magnetic particle testing was conducted on all of the existing welds on the 500-kV take-off structure and approach tower to confirm that they were all structurally sound. Areas that were determined to not be structurally sound or corroded on the 500-kV take-off structure and approach tower were wire brushed, welded and then painted with zinc rich paint.
After all of the welding and repairs were complete, insulators were added to the 500-kV take-off structure type II insulator assemblies, the jumpers were replaced and extended from the transmission line to the substation bus at the take-off structure as well as from the transmission line to the surge arrestors at the take-off structure. Extension hardware was also added to the south side 500-kV approach tower insulator assemblies and jumpers at the south side of the 500-KV approach tower were replaced. When the added vibration dampeners were installed to the span between the take-off structure and the approach tower and all other assemblies were in place, the lines were restrung. After close inspection by SWS, subcontractor and WAPA inspectors it was deemed safe to reenergize the line.
The completion date for this project was requested to be accelerated by approximately three weeks and with the cooperation of all parties the project was able to complete ahead of schedule without any additional cost to the end user.