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CHAPTERTWO <br />Alternatives <br />• Material storage sites, often with security measures such as fences and/or temporary storage <br />buildings, are erected. <br />• Staging areas are cleared for vehicles, equipment, and assembly of some components. <br />• Lay-down areas for transmission structures are prepared. <br />Construction <br />• Materials and equipment are delivered to the job site staging areas. <br />• Poles are unloaded at lay-down areas. <br />• Transmission poles are framed. <br />• If steel structures are used, then foundations for the structures are installed, bases are <br />grounded and the structures are erected. Holes are then augured into the earth where poles <br />are set. <br />• After poles are set, holes are backfilled and compacted. <br />• Structures are prepared for stringing. <br />Stringing <br />• Before conductor installation begins, temporary clearance structures are installed at road <br />crossings and other locations where the new conductors may accidentally come into contact <br />with electrical or communication facilities, or vehicular traffic during installation. <br />• Actual conductor-stringing operation begins with the installation of sheaves or stringing <br />blocks. The sheaves are rollers attached to the cross arm of the supporting structure. The <br />sheaves allow the individual conductor to be pulled through each structure until the <br />conductor is ready to be pulled up to the final tension position. <br />• When the pull and tension equipment is set in place, a sock line (a small cable used to pull in <br />the conductor) is pulled from pole to pole using ground equipment. <br />• After the sock line is installed, the conductor is attached to the sock line and pulled in, or <br />strung, using the tension-stringing method. This involves pulling the conductor through each <br />pole under controlled tension to keep the conductor elevated above crossing structures, roads, <br />and other facilities. <br />• After the conductor is pulled into place, sag is adjusted to apre-calculated level. The <br />conductor is clamped to the end of the hardware of each insulator as the sheaves are <br />removed. <br />• The final step of the conductor installation is to install vibration dampers and other <br />accessories. <br />Energizing Conductors <br />• Operational procedures are followed in energizing the lines. Step-by-step written operational <br />procedures are followed during the entire process to assure a safe startup. <br />2-46 <br />