When Physical Digital® was selected by Wood Group, the multinational aircraft MRO, to reverse engineer gas turbine components for remanufacture, we used the market leading GOM ATOS III 3D scanning systems to capture and analyse the data and to create a highly accurate model of the parts.
Reverse engineering gas turbine components
The aim of the project was to produce a model of the parts to reflect the original design intent, which through the manufacturing process had become less accurate. Engineering Manager Daniel Lainchbury explains the challenges and successes of the process and confirms the final results.
Reverse Engineering: Two stage project
Lainchbury explains: “We were approached by Wood Group to provide reverse engineering for these essential gas turbine parts. Our project developed in two stages: data analysis and validation to capture the original design intent of the parts, then modelling of the components. We were confident that our advanced in-house process would enable us to provide an enhanced-quality model of the components.”
For this project, the 3D scan data was captured in the US using the ATOS II system and provided to Physical Digital by Wood Group. The original digital scan projects could not be provided. Although Physical Digital were unable to check all quality parameters, using their vast experience of the GOM system enabled them to verify confidently the accuracy of the results.
Physical Digital recommends the use of the newer and even more accurate ATOS III TS which uses single and double camera capture mode and data verification. This allows the accurate capture of all surfaces and reduces the number of missing faces due to the angle of capture. The ATOS III is widely accepted in the industry as the leading scanner. For further information please visit GOM.
Initial data problems
The first challenge was to ensure the accuracy of the data supplied by Wood Group’s provider in the States, Digital Reality. This proved to be problematic: when interrogating the existing scan data, our team discovered areas where the data was not accurate enough or showed anomalies. It took a number of samples to ensure that the information would be suitable to create an accurate model of the components.
Stage One: Validation and Defining Geometry
Once the sample data had been selected, it was analysed to check where there might have been variations in design or where the components had deviated over time and use.
The samples of Wood Group’s gas turbine components were inspected to define the inner and outer geometries of the items. Special care was taken to ensure stability across all measurements types and an average size for each component was defined. Where appropriate, the engineers gained an average model using an average mesh command within the GOM professional inspection software.
Stage Two: Physical Digital’s in-house modelling process
The all-important reverse engineering phase of the project was ambitious in its remit: ‘We drew on the years of experience of our engineers when we created an in-house process to capture the original design intent of the gas turbine blades,’ Lainchbury explained. ‘It was vital to ensure that the aerofoil geometry would generate stable, high-quality models and to avoid ‘wobbly’ or poor-quality blades on remanufacture.’
Physical Digital used complex geometry calculations to improve the gas turbine blade’s aerofoil definition for Wood Group.
We worked closely with our client to ensure the precise definition of the blade’s aerofoil tip so that the model would be of the highest integrity. Then a series of complex geometrical calculations followed. This in-house modelling process ultimately resulted in a better-than-original model for the client to use for remanufacture. Faced with deviations in the data samples relating to the supporting case for the turbine blades, Lainchbury and his colleagues found that these related either to issues in the original manufacture or to usage over time. The Physical Digital process again resulted in a high integrity model for remanufacture.
Results and Achievements:
For Wood Group it was essential to ensure the integrity of its high-cost and high-impact components such as the turbine blade and support case as described here. For remanufacture it is imperative to use wholly accurate measurements.
Physical Digital, a company with vast experience of the requirements of the aerospace and automotive industries, is uniquely placed to provide that assurance and produce accurate models and drawings of the original design intent of the components. Lainchbury was delighted with the results of this project: ‘We provided models for the client which were more accurate than the original designs: better than new!’
To discuss your reverse engineering requirements, whether for remanufacture or to improve prototype designs, contact us or call 01483 750200.