GE robot inspectors deployed to check Australian power plants

General Electric (GE) has signed an agreement to deploy advanced robotic inspections of US-based electric company Alinta Energy’s gas-fired power plants in Australia and New Zealand.

GE’s “little” robots will perform the inspections and have been developed over several years by Alstom Inspection Robotics as part of GE’s November 2015 acquisition of Alstom for $13.8bn.

GE's TurboRotoscan detects stress corrosion cracks at the inner and outer surface of the retaining ring on wide range of generators - image courtesy of GE
GE’s TurboRotoscan detects stress corrosion cracks at the inner and outer surface of the retaining ring on wide range of generators – image courtesy of GE

GE Diris and TurboRotoscan inspection systems will alert Alinta Energy to potential generator issues and give it time to evaluate its options.

The Diris robot will provide Alinta Energy with modern robotic instrumentation and tooling to allow fast and reliable remote inspection of the turbogenerator, while also performing critical tests of the generator stator iron core laminations, stator radial wedging system and conducting a visual (video-type) inspection of the inside surfaces of the rotor and stator.

The video inspection features the GE service engineer looking for signs of deterioration, such as delamination of the core packets, and checks for foreign objects and contamination.

The inspection robots deployed by GE signal a new era of optimising machine productivity and reducing the risk of damage to expensive assets.

What is in store for GE’s little robots

Under the terms of the inspection agreement, GE’s little robots will inspect 19 generators manufactured by GE, Alstom, Mitsubishi, and Brush at seven of Alinta Energy’s gas-fired power plants in Australia and New Zealand.

The GE robots inspect save unnecessary downtime by enabling the inspection of generator components without the removal of the rotor.

GE’s Diris ‘Small’ robot provided to Alinta Energy is a precision tool that sends probes through air gaps as small as 9mm to conduct critical testing of the generator components, as well as the TurboRotoscan inspection which tests the condition of the rotor retaining rings.

Not having to remove the generator rotors for inspection and that the technology could be used on non-GE units were the key factors that Alinta Energy manager, engineering services – power generation, Gareth Williams, said GE’s robots would provide.

“We worked closely with GE’s team and our insurance company to demonstrate the benefits of the DIRIS and TurboRotoscan technologies for ensuring effective generator inspections,” he said.

“Proving the technology’s reliability was important because the generator monitoring system provides the current condition of the generator and indicates any issues or early warnings of failures,

“It also provides us with greater flexibility as the inspection work can be done while the generator rotor remains in place,

“The biggest win for us was the ability to use this technology on non-GE units and apply it across our whole fleet, this makes such inspections quicker and easier to perform and is endorsed as a best practice by our insurance company, which indicates that most generator claims arise through rotor removal and replacement activities.”

The ability for the GE robots to inspect the generators without the need to remove the rotors is vital for Alinta Energy’s operations, as it will save the company the added costs of three weeks in generator downtime which came is required to remove the rotor for inspections.

Robot inspections also reduce the risk for the unnecessary risk of damage which comes from having to remove the rotor, and can be performed within two to three days rather than the three-week period of the past inspections.

The new generator inspections for Alinta Energy’s operations started this month and will be performed through to 2020.