Keep workers safe, costs low
Inspecting critical assets such as boilers is complicated, especially those located in difficult-to-reach or confined spaces, requiring a special permit for entry. Accessing these spaces often puts workers in uncomfortable and potentially hazardous situations. However, industrial robots are available so that plant managers can make tasks like boiler inspections efficient and safe for workers.
Midwest utility company Ameren Missouri is well aware of the complications associated with boiler inspections process. During any outage, Ameren Missouri’s inspection crew conducts a full first-look inspection of its boilers, examining components for high-pressure steam leaks and gauging the extent of slag and material buildup before any work begins.
Complicating the process is how difficult it is to see slag buildup on assets like super heaters, unless a worker is suspended 200 feet in the air in a sky-climber or floating platform. If unchecked, falling slag can damage expensive ash removal systems below and pose worker safety risk. Other issues, such as uncertainty related to maintenance and time resources required to fix tube leaks and the safety of workers crawling through confined spaces during lower mud drum inspections, contribute to the need for sound maintenance planning.
Ameren Missouri recently approached Sarcos Robotics – a global producer of robots that augment humans to enhance productivity and safety – to simplify the boiler inspection process, and create a safer environment.
Calling on the guardian
Sarcos Robotics’ Guardian S robot augments human-based inspections by operating in challenging environments and removing workers from potentially hazardous situations or tight, confined spaces. The company wanted to capture high-quality visual data from the robot’s platform to derive accurate assessment of boiler condition to streamline the scope of maintenance and reduce boiler downtime.
Sarcos provided Ameren Missouri with a magnetic version of the robot’s platform, which collects visual and sensor data while operating in confined spaces, climbing vertically on walls to access systems high up in the boiler. The Sarcos and Ameren Missouri teams completed a first-look inspection of the boiler’s superheaters and waterwall tubes, determining slag buildup, leak location and extent of repairs needed. The robot also inspected lower water wall heaters and was inserted into the mud drum to visually assess tube penetrations.
Impact safety and bottom line
Ameren Missouri reaped myriad benefits. Using the robot for first-look boiler inspection meant employees need not enter its mud drums. Ameren Missouri team estimates time required to complete mud drum inspections was reduced 16 to 32 man-hours.
For outages caused by boiler tube leaks, the robot completed a full inspection in one day versus the typical three to five days workers required. In the future, robot-gathered data will enable better-informed decisions and enhanced maintenance plans. It also will likely shorten overall time the boiler units are out of service reduce inspection costs.
“As early adopters of the Guardian S, we’re learning about it collaboratively, and Sarcos is working with us to experiment and identify new use cases in our facilities,” said Bill Henning, manager of boiler and coal mill services, Ameren Missouri.
Use cases on the horizon
After the boiler inspection was completed, Ameren Missouri worked with Sarcos to successfully test the robot on a first-look penstock inspection in its pump storage facility. Other potential opportunities include testing the robot’s applicability in other Ameren Missouri facilities.
By implementing the robotic platform over time to capture high-definition video and imagery, Ameren Missouri expects it will be able to move toward a more condition-based maintenance planning, whereby they will only schedule maintenance when needed, rather than relying on a time-based maintenance plan. This will allow Ameren Missouri to reduce downtime costs, including worker resources, parts, tools, infrastructure and the need to procure alternative energy sources for customers during these periods.
“I am a firm believer in this type of technology,” said Henning. “The maneuverability of the robot is a big plus. And, any time we can allow non-humans to do something for us, that’s always a positive. Ameren Misouri will continue to look at new ways for the Guardian S to assist our workers beyond boiler inspections in order to keep them safe. Ultimately, reducing maintenance costs and improving efficiencies saves our customers money.”