The importance of metrology in manufacturing

What is metrology in manufacturing? 

To provide a broad definition, metrology is concerned with the science of measurement and its application. 

Technological advancements linked to accuracy, sustainability and cost-saving are pushing the manufacturing industry to produce parts more efficiently with higher rates of quality. It is in this area that the power of metrology comes into its own for manufacturing. 

Metrology is concerned with quality assurance and the tools to provide calibration, in-process measurements, process control, automation and data collection. For manufacturers, this has often looked like physical metrology instruments (i.e. gauges and CMMs) but with advancements in technology, integrated software-based metrology options have emerged, providing more benefits in terms of automation, lights-out CNC machining and IoT.

This integrated use of metrology can often be the difference between successful and unsuccessful manufacturing processes. 

How can metrology improve manufacturing processes?

Most manufacturers will be familiar with metrology in the form of gauges, lasers or CMMs to either calibrate their manufacturing equipment or inspect their parts. But metrology has a much bigger remit than that; it can take the guesswork and uncertainty out of all manufacturing processes. 

Removing uncertainty and improving the quality of machined parts requires metrology-quality data – which requires CNC spindle probes. Machine tool probing is now an established metrological best practice in the CNC manufacturing industry working with types of metrology software to improve every stage of manufacturing and CNC machining processes. 

Let’s look at some of these areas in more depth. 

Pre-production Improvements
If you’re manufacturing high-value parts, it is imperative to check everything is setup, calibrated and working accurately before parts are machined. 

This includes the CNC probes themselves. Metrology devices, such as AutoClock from MSP, can setup the calibration artefact used to calibrate the probe to micron-accurate levels within a few minutes. And automatically, which is key to properly ensure no errors are present within the setup and won’t affect the rest of the process. 

The next stage is ensuring the probe is properly calibrated. There are different ways of using metrology for this but the simplest is NC-Checker from MSP. This runs automatically after AutoClock to calibrate the probe in 5-axis. Proper calibration ensures accurate measurements will be produced for any processes the probe is used for (e.g. machine setup, part setup, verification and inspection). 

Metrology is also important for understanding if CNC machines are performing accurately ahead of production too. Metrology software is available within the industry that can highlight if CNC machines are capable of machining parts within tolerance and a myriad of other information such as, showing if a crash has affected the machine, the difference between two machines or if the temperature / environment is having a detrimental effect on machine performance. 

If that wasn’t enough to show how useful metrology within the CNC manufacturing industry can be, it is also effective for improving part setup processes. Powerful metrology software exists which can confirm if a part’s condition of supply is good, can calculate the correct part alignment (and automatically upload it to the controller) and help connect part alignment and machining processes so everything can run 24/7 lights-out. 

Post-Production Improvements
Inspection is already a well-known area for metrology with the use of CMMs or laser inspection equipment. However, as technology, and therefore, metrology, advances it is becoming possible to inspect parts while they are still on the machine tool bed. This adds further improvements to the inspection process as no extra equipment is needed and less elements are involved for safer processes. It also means large parts, unable to fit on the CMM, can go through similar inspection processes.