Inside a Gas Turbine Stack: Inspections Without Outages Using Elios

Elios was used to complete the inspection of a gas turbine stack at a major energy facility – saving thousands of euros and days of time.

Download the PDF of the case study here
uniper_logo_small

Benefits in a nutshell

DOWNTIME

No downtime. Visual inspection performed in one hour instead of 3 days.

COSTS

9000 Euros of direct savings (manpower, crane and scaffolding rental) for 1 hour of inspection.

SAFETY

No human entry in the stack. No related paperwork.

 

Introduction

Uniper SE is a major energy company servicing Europe and the U.S. A spin-off of German utility giant E.On, “Uniper” is a hybrid of the words “unique” and “performance”: and their newest method of inspection bears out their name. An inspection team using the collision-tolerant Elios operating inside the stack was able to fly past baffles to perform an inspection in only an hour – saving 3 days of work and thousands of euros, all without a pause in production.

 

elios-inside-the-dark-gas-turbine

 

Designed to fly in dark and inaccessible spaces, Elios is uniquely equipped to provide views of the stack interior

 

Customer Needs

Uniper’s open cycle gas turbine stacks are huge – and hot. At 570 degrees Celsius – over 1000 degrees Fahrenheit – there is no question of human inspection while the turbine is operating, explains Mikael Nilsson, Uniper (Sydkraft Thermal Power AB) Maintenance Manager. The units act as stand-by reserve power plants and can be remotely activated at any time by the customer (Transmission Systems Operator). Inspections must take place at least every 3 years, and they must be carefully timed to take advantage of production downtime.

Traditionally, the inspection of the top half of the stack is performed by lowering workers into the space with a mobile crane. For safety reasons, the machine must be offline and isolated, with fuel and ignition systems turned off. The inspection requires extensive paperwork and a specialized work permit: it can take several hours to get the work permit and isolations done. The inspection itself takes about 30 minutes, but de-isolation and return to service take another hour.

That’s only half of the job. The inspectors in the crane can’t move past the baffles on the interior of the stack: to inspect the lower half, workers generally use scaffolding. The scaffolding takes a full day to erect and another to dismantle after the inspection is complete, requiring a full 3 days of lost production time.

It’s not only time consuming; it’s an expensive process. With 1 or 2 inspectors in the basket and another staff member to operate the crane, inspecting the top half of the stack alone can cost over 500 euros just in manpower. Inspecting the bottom of the stack is much more expensive – the scaffolding alone costs the company about 8000 euros.

 

elios-flying-to-the-top-of-the-chimney

 

We don’t even have to involve the customer at all, and the customer appreciates that.

- Mikael Nilsson, Maintenance Manager, Uniper

 

Solution

Nilsson’s team used the Elios to fly inside the stack, flying past the baffles and inspecting the entire area in one mission. Designed to fly in dark and inaccessible spaces, Elios is uniquely equipped to provide views of the stack interior. With the footage from Elios, inspectors were able to gather all of the data they needed on the state of the surfaces and the mantle, looking at support brackets, welds, and bolts for potential problems.

Using Elios, the team didn’t require the extensive paperwork and work permits required to send people into the stack, or approval from the customer since the unit was still available for dispatch– something that saved both time and effort. “We don’t even have to involve the customer at all,” says Nilsson. “And the customer appreciates that.”

 

 

Results

The results of the mission speak for themselves. The one hour of inspection time using Elios is a major gain over the usual 3 days of lost production. The cost of a 1 hour mission with Elios compared to almost 9000 euros for a standard inspection is another compelling advantage.

Perhaps the major gain for the inspection team using Elios is in operations management. The usual 3 year scheduled inspections are carefully timed to take advantage of outages, to avoid having to take production down just for the inspection process. With a drone, however, managers can inspect before the outage – and be ready to fix any problems during the regularly scheduled downtime. “You can do much better planning,” says Nilsson.

 

checking-welding-of-silencer-suspension

 

YOU CAN DO MUCH BETTER PLANING.

- Mikael Nilsson, Maintenance Manager, Uniper

 

Conclusion

Elios offers major advantages for Uniper’s inspection teams, saving thousands of euros and days of downtime. By using a drone instead of human inspectors, the extensive paperwork and technical safety processes required to put people into the stack can be eliminated. Most importantly, management and planning processes are improved by being able to perform inspections outside of regularly scheduled outages.

Nilsson says that Uniper is more than pleased with the outcome. “They think it’s great that we reduce downtime and increase the availability,” he says. “We’ll definitely use drones more frequently.”

Let's look at your application together

 

The best way to get started with indoor drone inspection is probably by understanding if there is a fit with the application you have in mind.

We offer to provide you with a free personalized consultancy service to do exactly that.

Request your Application Assessment r

SEE ALSO

Infrastructure & Utilities

Elios was used to complete the inspection of a damaged section of sewer infrastructure in Barcelona, Spain.

Food & Beverage

Elios was used to complete a complex indoor ceiling inspection over the factory floor in the Pilsner Urquell brewery, in less than half the time of […]

Mining

Elios is used for mine facility and equipment inspections in Copper mines of Northern Chile, flying in the dangerous and confined areas around mining […]

Infrastructure & Utilities

Elios is used for bridge inspections in Minnesota, USA, navigating the difficult to reach spaces under bridges between beams and inside of box girders. […]

Mining

Flyability’s collision tolerant Elios drone has performed multiple missions in the North American Palladium (NAP) Lac des Iles mine near Thunder Bay, […]

Power Generation

Flyability’s collision-tolerant Elios UAV has been used at a major nuclear power plant, proving the case for Elios in the normally inaccessible spaces of […]

Aeronautical

The jet engine test beds used in the aeronautical industry for Quality Control and R&D require strict maintenance. Traditional methods of inspection […]

Maritime

CMA CGM required the internal inspection of a ballast tank of one of its container ships, the CMA CGM ANDROMEDA. Flying in complex and pitch-dark confined […]

Chemicals

Pulp, which is the raw material used in the manufacture of paper, is prepared by chemically or mechanically separating cellulose fibers from wood, fiber […]

Chemicals

Novozymes, a world leader in biological solutions, is looking for solutions improving the quality of its infrastructure’s maintenance process while […]

Oil & Gas Chemicals

TAU AG, an asset manager in charge of a tank farm in Muttenz Switzerland for the BP and Avia oil companies, required the internal inspection of […]

Power Generation

Ronik Inspectioneering, a Dutch inspection company, together with Flyability performed the general visual inspection of the boiler of a coal-fired power […]

Oil & Gas Chemicals

A prevalent tool in energy production and storage are pressure vessels, which hold gases and liquids at high pressures. Vessels are subject to regular […]