Last Monday, Reliance’s first- and second-year apprentices visited the National Physical Laboratory (NPL) in Huddersfield with Training School Manager, Robert Farrell, to learn about high-precision metrology.
When we arrived, the team at NPL gave us a presentation which started with an explanation of what metrology is. Next, they talked about the history of measurement, starting with the cubit from ancient Egypt, then the yard (the distance from King Henry I’s nose to his thumb) and then the metre, which was defined as one ten-millionth of the distance from the North Pole to the equator through Paris. The world (mostly) used this and would refer back to a physical artefact, but eventually that was too inaccurate, so a new method was devised using maths to define the metre much more accurately.
After the presentation, we were taken on tours around some of the laboratories, including the R&D lab, where they were running experiments using sensors on CNC machines (microphones, vibration sensors and temperature sensors) to check part accuracy and identify defects before they even leave the machine. They also showed us large-volume metrology, which is used to measure things like turbines and even robots.
Then we went back to the presentation room for some more presentations. One was given by their new apprentice about what she has been learning, along with a more in-depth explanation of large-volume metrology and the use of sensors on CNC machines.
Overall, I really enjoyed the visit. I learnt just how much metrology impacts my daily life, more about the history of measurement and how machinists can often hear subtle noises in a CNC machine that indicate a part will come out wrong. The highlight for me was the presentation about all the strange things the NPL has been contracted to measure over the years. I also liked seeing their R&D labs. It was interesting to see the different projects going on at the time. Thank you to everyone at the NPL for having us!
Finlay
