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Case Study
Optimising assembly processes through in-situ measurement
Project challenges
The MTC worked with Rolls-Royce to develop a methodology for measuring bolt clamping load in-situ within a restricted geometry environment.
Business challenge
Process Innovation
Sector
Aerospace
SME
Technology or capability
Metrology & NDT
The Challenge
- Assembly of a critical bolted joint within a Rolls-Royce engine is currently reliable, but there were opportunities to improve and optimise the design for the fitter
- Future product designs are likely to require ever increasing clamping load capability, driving the requirement for improved and more efficient methods
- The bolted joint is located within a restricted and difficult-to-access geometry, severely limiting the options for in-situ measurement
MTC's Solution
- Identified the use of ultrasonic technology to enable in-situ measurement of bolt clamping load
- Developed a functional tooling prototype to implement ultrasonic measurement capability within an existing tooling footprint
- Designed and manufactured a suite of test hardware to prove the technology and the process
- Conducted a detailed series of trials to prove performance, collect relevant parameters, and enable practical usage of technique on development engine build
Can I pass on my congratulations to the Rolls-Royce/MTC team… it’s great to have a project go from early ideas and concepts and then see it all the way through to actually being used to build an engine.
Alan Pardoe, Partnership Manager, Rolls-Royce
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The Outcome
- Creation of a bolt design ensuring correct ultrasonic functionality
- Development of a functional tooling prototype that enables ultrasonic measurement of bolt clamping
load to within +/- 5kN - Creation of representative ‘engine core’ test hardware that enables a full simulation of the bolted joint
assembly process - Test bench’ hardware that enables single-bolt testing for ongoing calibration
- Ongoing support to determine specific material and geometry factors for development engine bolt designs
Benefits to the Client
- Significant improvement in accuracy of assembly clamping load measurement, enabling significant reduction in reserve factors
- Implementation of a measurement system that directly displays bolt clamping load during operation; and enables straightforward data collection for improved traceability
- Implementation within existing tooling means minimal impact to current assembly process
- Provision of test hardware to enable demonstration of process, operator training, and future testing using
new bolt materials - Provision of measurement data and corresponding statistical analysis in order to support faster technology development/deployment
- Functional tooling prototype that has been successfully used in assembly of engine demonstrator
The combined Rolls-Royce and MTC team has produced an effective and efficient methodology which will provide many benefits to industry.
Geraint Prisk, Manufacturing Engineering Lead UltraFan, Rolls Royce
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