Research cuts time-lag between component manufacture and CMM checks

When a component is manufactured, it typically leaves the CNC machine at an elevated temperature, and must be cooled before it can be precisely measured in a Coordinate Measuring Machine (CMM).

But since engineers have no way of knowing precisely when the part will drop to the desired temperature of 20^oC, they typically play it safe and wait for 8-24 hours before checking it in the CMM, according to Dr Naeem Mian at the University of Huddersfield.

This creates a log jam in production, and means expensive CMMs are left standing idle.

Now Mian and his colleagues have found that this wait time could be slashed, potentially to just a few minutes. Their research is expected to give engineering firms a technique for calculating how long it takes for a component’s temperature to be stabilised so that it can safely be measured by a CMM.

The researchers carried out a series of experiments to determine the Thermal Contact Conductance (TCC) values of different components, or their ability to conduct heat to a surface, in a bid to calculate how long it takes for their temperature to stabilise. He then used Finite Element Analysis (FEA) to validate his findings.