Michels® Power construction crew, headquartered in Brownsville, Wisconsin, has been working on a mammoth project replacing copper high tension lines with cabled aluminum lines from Readsboro, Vermont, to a substation in Wendell, Massachusetts. The new cables will still carry power at 115 KV but will carry a flow of twice the amperage as the old copper lines. The increased power load siphon off to feed communities at Millbury, MA in the Worcester, MA area.
Michels crews have erected one new tower and are making repairs where necessary on the existing towers. The main thrust of the project is to replace copper high-tension lines with cabled aluminum lines in order to upgrade the lines to carry more power. The company has slogged on in good weather and bad, through swamps, mud and record snowfalls, since October of 2014. The project is about 90% complete.
The new conductors have a composite ceramic core of nine strands wrapped with 24 aluminum strands. The individual composite core strands are brittle and snap like dry spaghetti when subjected to severe deflection, but they have high tensile strength so that the lines do not stretch or sag under tension, especially when subject to high ambient temperatures as copper lines are apt to do. The ceramic core strands cabled together and wrapped with aluminum strands creates a line that has extraordinary attributes, but must be handled differently than copper lines. When an aluminum line is attached to an insulator, it must have a special connector clamped onto it. A jumper line to the outgoing line bridges the insulator.
Michels Power linemen are also installing new porcelain insulators for the new lines. Though high line crews often work with live high voltage lines, in this instance power has been shut off to expedite the work on the more than 250 tower structures along the 30-mile route.
As a part of the environmental planning process, crews lay down hardwood timber mats to bridge streams and wetlands as mapped by an environmental company. An operator sets the timber mats with a Cat loader equipped with forks. He places them where designated, directly onto wetlands, though sometimes they need to build bridges over small streams or deep ravines.
For this project the crew’s equipment lineup includes 11 Ford pickup trucks, an Army surplus 6 X 6 all-wheel drive truck, 5 bucket lift trucks, 2 digger derrick trucks, 3 cranes, 1 Peterbilt lowboy, 1 Caterpillar forklift, 2 Wagner- Smith pullers, 1 Wagner-Smith V-groover, 3 Volvo Excavators, 3 Volvo Payloaders, 2 Caterpillar bulldozers, a Snow Cat and an office trailer. Because of the high salvage value of the copper material that they remove, the scrap copper line is kept in secure dumpsters, under lock and key.