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Moving equipment smarter, faster

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​Moving equipment smarter, faster Every day Western employees think of ways to improve how they do their jobs. As just one example, Sierra Nevada’s Elverta electrician crew built a new tool to help move heavy equipment in a new and more efficient way. 

Maintaining Western’s transmission system and assets requires hard work, collaboration and drive. Ensuring old parts are replaced with new parts can be a heavy task, literally.

In October 2011, Elverta electricians were tasked to replace Elverta 582 high-voltage oil circuit breaker at the Elverta Substation in northern California with a new sulfur hexafluoride, or SF6, circuit breaker. This required moving a 9,800-pound SF6 circuit breaker, and figuring out how to get the old oil breaker out of its position and maneuvering the SF6 breaker into place.

Decision sparked by future needs, cost savings

According to team discussions, there were two practical and viable options. The first was to completely remove a 230-kilovolt switch; coordinate a main bus outage; remove a light pole so the team could move the old and new breakers as needed; and hire a crane company to use a large crane to lift the equipment in the constrained radius. The second option was to construct a trailer that could hold the 9,800-pound breaker that would be low enough to drive through the 230-kV substation yard without contacting any energized equipment; coordinate a short outage in conjunction with switching out relays in the control room; and rent a crane the team could maneuver themselves. Because the rest of the oil circuit breakers in the yard would have to be replaced in the future and because the first option was more costly and time consuming over time, the team decided to construct a breaker trailer.

When transporting large circuit breakers in the past, electricians would have to remove switches and other obstacles in the yard to clear enough space to get the breaker in place, then park a big rig and crane as close as possible and “leap frog” the unit over to its location. Using the breaker trailer is safer and saves time and money because the electricians no longer have to spend funds on a large crane to complete the task. “Coming up with the breaker trailer idea and implementing its construction illustrates of how the Elverta crew uses innovation, technology and know-how to improve how this job is completed,” said Elverta Lineman Joel Carrillo. 

Designing path to improvement  Elverta crew is getting ready to drive the new SF6 circuit breaker through the Elverta 230-kV Substation Yard.

Next, the project team reviewed manufacturer’s drawings to find the breaker’s center of gravity and weight. Apprentice Electrician Eduardo Arellano Flores began designing the trailer. Before his career at Western, Arellano Flores worked for an agriculture equipment manufacturer. He gained extensive knowledge and experience designing trailers and was a certified welder.

Once the final design was agreed upon, the team began building the trailer. Construction took about eight days from start to finish. The trailer featured some key components like nylon tie downs, 8,000-pound axles with electric breaks, a fifth wheel turn table for tight steering and a two-inch ball coupler so the trailer could be towed by a truck, tractor or utility task vehicle. The finished product was covered with a silver-powder-coat finish so it would last for years.

“On Oct. 3, 2011, the day of the outage, everything went as planned. We drained the oil out of the old oil circuit breaker, cut it into thirds and moved it out of the way. Next, we loaded the new SF6 breaker onto the trailer with a 15-ton crane. After securing the breaker to the trailer, we towed the new breaker through the very narrow, energized 230-kV yard. Once the breaker was in place, we lifted and set it with the crane that was previously used to load the breaker on the trailer,” said Arellano Flores.

The construction of the breaker trailer was made possible by the creativity and partnership of Elverta crew Foreman III Electrician Jim Higgins; electricians Sam Lake, Dana Trimble and Kurt Zastrow; and Arellano Flores. From start to finish everyone involved played a key role in the success of switching out the circuit breakers with minimal outages, cost and zero sacrifice to Western’s power system reliability.

Recently, Senior Vice President and Sierra Nevada Regional Manager Subhash Paluru visited the Elverta crew, which inspired the team to discuss the process improvement they have accomplished in recent years. “I am so glad that I have met the entire Elverta crew and was able to discuss the technology and innovation topic with them. Stories like this one—building something so that you can perform a job better—motivate our entire workforce. My thanks goes to all who were involved in designing the breaker trailer and also to the foreman and management team for fostering a collaborative environment.”

​Oil vs. SF6 circuit breaker

High-voltage circuit breakers are automatic switch devices that connect and break electricity currents. An oil breaker is different from a sulfur hexafluoride, or SF6, breaker because it is filled with oil instead of SF6. Both the oil and SF6 within the circuit breakers are used to extinguish an electric arc. Through a high-voltage circuit breaker, an electric arc that is too high for the transmission system to handle will be drawn in oil or SF6 to dissipate or extinguish the arc.

On Oct. 3, 2011, the Elverta crew is getting ready to drive the new SF6 circuit breaker through the Elverta 230-kV Substation Yard in Sierra Nevada using the newly construction breaker trailer hitched to a tractor. The old oil breaker circuit breaker has already been removed. (Photo by Eduardo Arellano Flores) See more breaker trailer photos on Western's Flickr.

Page Last Updated: 7/13/2015 10:35 AM