Wide blue yonder
- August 28, 2017
- ReMaTec News
Rolls-Royce is among the most recognisable, blue-chip brands in history. One of the world’s largest producers of aero engines, it also has a thriving reman operation. Tim Maughan speaks to the company’s Singapore-based chief of materials engineering, Nick Weeks
To many people, the name “Rolls-Royce” perhaps used to be best known as a luxury car manufacturer: brands such as Silver Shadow, Phantom and Corniche are purred over by collectors and enthusiasts wherever the internal combustion engine is used. But Rolls-Royce Motor Cars, sold in 1998, was only ever part of the story. Rolls-Royce has long been a giant in the world of aviation: the company is one of the largest producers of aero engines for large civil aircraft and corporate jets, and the second largest provider of defence aero engines in the world - and it may come as a surprise to some that this world-famous firm is heavily involved in remanufacturing too. Nick Weeks, chief of materials engineering, Asia Pacific Region, heads a Singapore-based team, with a number of personnel also based in Japan, China and Taiwan. “We focus on our Trent engines,” he explains. “All of them go through a life cycle which involves them getting overhauled in overhaul shops. The list includes a shop up in Hong Kong where we have a joint venture with Cathay Pacific, and one in Singapore, where we have a joint venture with Singapore Airlines.”
The Trent ‘family’
The term ‘Trent’ refers to the family of the firm’s large gas turbine aeroengines. There are six different Trent models in service: Trent 500, Trent 700, Trent 800, Trent 900, Trent 1000 and Trent XWB. They are bought by more than 400 airlines, and lessors, across the world. The company’s Singapore manufacturing plant, which was opened in 2012, makes the Trent 900 and the Trent 1000. Soon, the Trent 7000 will also be produced there. At full capacity, the facility will be able to produce 250 engines a year. Rolls-Royce says that, in the remanufacturing process, all parts are cleaned before it can be ascertained what work needs to be done. This process is known as ‘sentencing’, a combination of visual assessment and non-destructive methods such as ultrasonic or eddycurrent inspection. A dimensional check is also carried out. The parts are then sentenced as either for service, scrap or requiring rework. The engines are typically brought into a maintenanceand overhaul shop, where they will be disassembled. The parts in need of remanufacture are then shipped to a component repair facility. An example of such a component is the nozzle guide vane, which directs the airflow onto the turbine blade in an engine. These are shipped to the facility, based on airline contracts. Repairs are completed and the component is returned in 14 days.
“It’s a bit like when you take your car for a service after 10,000 miles. There are major and minor inspections you have to do at different points in the engine’s lifecycle” - Nick Weeks
Safety and reliability
Remanufacturing, says Rolls-Royce, has always been part of the aero engine business model. At no stage does the reman process reduce an engine’s safety, reliability or performance. Weeks explains: “It’s a bit like when you take your car for a service after 10,000 miles, or whatever it is these days. There are major and minor inspections you have to do at different points in the engine’s lifecycle. We will do several minor checks, and there will be a major overhaul at certain amounts of engine cycles. At that point, we will strip down the engine into separate modules, and then we will strip down each module. We will inspect each of the parts, then we will either replace them, or we may repair that particular component, and put that back in the engine – and that is the remanufacturing element to it.” The company divides parts up into what it calls “different levels of criticality” when it comes to safety. “You have got something like a washer,” says Weeks. “If it had a defect, it can’t impact the safety of an engine. That would be a non-critical part. We then have what are called sensitive components, which could affect the running of the engine, and we have critical parts that could affect the whole aircraft.”
Significantly, although reman is very much part of the civil aviation business, it does have a limitation. Critical parts have a strictly de ned lifespan, and when that duration comes to an end, the remanufacturers do not get started on them: the component is simply replaced. But before that, there is so much that this leading player in aviation reman can do. And you would not bet against Rolls-Royce forging new horizons for its engines in the skies - and elsewhere.