Keeping the lights on for customers in the desert Southwest is a crucial and continual mission, especially during hot summer months. To do so, linemen for Tucson Electric Power (TEP) often must work in remote locations that are nearly impossible to access with a bucket truck or crane.
For example, canyons loomed on both sides of a 345-kV lattice tower in New Mexico where TEP linemen recently needed to perform maintenance at the hot plate on an outside phase. The crew had two options: take the line out of service or access the area from the ground up.
Shutting down a transmission line for repairs could cost hundreds of thousands of dollars a day in lost revenue and place additional stress on adjacent circuits. As an alternative, linemen can work barehand while keeping the line in service, but they would need to be able to use a large crane or truck. That was not an option at this site because of the rugged terrain. Instead, they would need to climb the tower, test and ground the line, and hang a fiberglass hook ladder to access the work site. Accomplishing these tasks while using 100% fall protection equipment could take four to six hours and place significant physical strain on the linemen.
Reliable service for customers and safety for employees are big priorities for TEP, but the company also values innovation, efficiency and keeping costs low. That’s why TEP was willing to consider a new approach to accessing remote facilities.
Observing a Demo
In search of a better alternative, TEP turned to its trainer, Jim McDonald of Power Line Training Consultants. He knew of a product manufactured by Atlas Devices that could be used to quickly and safely ascend and descend a tower in remote locations. For 12 years, the military — including special operations forces — have used this device, and Atlas recently introduced it to the electric utility industry.
McDonald invited Western Area Power Administration employees to demonstrate the product at TEP’s training center. TEP immediately recognized its potential as a flexible, cost-effective tool that would enhance safety for its employees. TEP purchased its first device in December and trained its crews how to use it in a de-energized setting.
The Atlas Devices APA-5 powered ascender originally came with a 10-mm rope capability, but TEP uses a 13-mm rope in its rope and rescue program. For efficiency, TEP didn’t want to stock two different sizes ropes. Atlas Devices used the feedback and adjusted its device to accommodate 13-mm ropes, creating the APA-5-U utility model. In addition, for TEP to maintain its operational capability, TEP sent Atlas its previously purchased device, which was designed for the 10-mm rope. The manufacturer retrofitted the device to accommodate 13-mm at no cost while providing an additional system in the interim.
The Atlas Tower Kit is comprised of a battery-powered rope ascender, compressor and rope launcher. The user launches the non-conductive dielectric projectile and rope over the main members of the arm or over the top of the tower, depending on the work location.
During the repair work in New Mexico, TEP linemen used the launcher’s precision, military-style accuracy to shoot the rope and projectile through lattice structure arms into the exact "diamond" where it needed to be from about 100 ft away. This placement enabled them to access the hot plate from the outside of the conductors, away from the tower. This particular maintenance work order was to install a cotter key on the hot plate. The line crew used the ascender to access the hot plate, install the cotter key and descend safely back down to the ground.
Using traditional methods, this repair would take four to six hours, requiring linemen to climb the tower, ground the line, hang the ladder, ascend and descend the ladder, perform the repair, and then tear it all down once complete. With the ascender, it took about 12 minutes, and the linemen were able to stay truly 100% fall restraint compliant the entire time.
Participating in Training
To perform live-line work, TEP has a dedicated transmission work group that participates in training with McDonald every year. This crew predominantly works on 46-kV to 500-kV lines. At TEP, apprentices rotate through different work groups including underground, maintenance and transmission. Before joining the barehand crew, however, they are required not only to top out as journeymen, but also to participate in extra training and gain more real-world experience.
Each year, the specialized transmission team reviews how to become more efficient on energized 345-kV and 500-kV work practices and rope-rescue procedures, and also establishes contingency plans for when operations do not go as expected. They learn about new work methods and ways to use new tools during these sessions, and study advanced first aid training in case an emergency occurs in a remote area.
This team, which includes three crew leaders and nine journeymen linemen, is hot stick certified, and trained in barehand, rope access and rope rescue. The linemen jumped at the opportunity to use this device and expand its utility with their creativity, resourcefulness and vision.
Today, this transmission crew uses the Atlas device for more than just ascending a tower in a remote location. Linemen use it as a capstan for lifting loads, in place of a hand line, in conjunction with barehand techniques on hot ropes. They also have figured out how to use the ascender as a life-rated capstan to perform ground-based rescues, tower-based rescues and self-rescues.
Reaping Benefits
By using the Atlas powered ascender, TEP was able to achieve significant time savings, and its line crews could use their rope access training in a very efficient manner. In addition, the new technique was much easier on the crew members’ bodies as they were no longer required to use repetitive motions to climb a 125-ft lattice tower.
Once the ropes were in place, it not only became very efficient for the linemen to reach the necessary elevation, but also safer than traditional methods, such as using a capstan. With the Atlas device, there is no possibility of losing control once it has been loaded correctly because of its self-locking brake system.
TEP is also exploring another benefit of using Atlas equipment: reduced disturbance of environmentally sensitive or protected areas. For example, TEP transmission lines cross lands owned by the Navajo Nation, Zuni Pueblo and the American Forest Service. To access facilities in remote locations on these lands, TEP must request permission to build roads that can accommodate large pieces of equipment. This process can take up to a year. However, with Atlas equipment, crews can access equipment with existing roads, eliminating the need to wait for environmental, plant and cultural studies at work sites.
Although TEP coordinates efforts with land owners, the company doesn’t typically need permits because it can access transmission facilities via overland travel and with all-terrain vehicles. This also offers cost savings by reducing or eliminating requirements to obtain road-building permits and construction of roads.
TEP’s elite transmission team has used the Atlas Tower Kit to perform work in a safe and timely manner, and with a lighter footprint, even in hard-to-access work areas. Improving productivity, increasing field safety and reducing environmental impact are important goals for TEP, along with increasing the safety and productivity of its field workforce. ♦
Greg Wildman is a supervisor for the transmission group for Tucson Electric Power. Prior to serving in this position, he served as a journeyman lineman and team lead for the utility. He has worked in the electric utility industry for 28 years.
