Micro Bore

Ongoing Development of Micro-Bore Orifice Systems


A project to investigate the performance of Critical Flow restriction orifices having bores less than 0.5mm

50miron orifice bore


The performance of critical flow orifice plates and nozzles is well known for bores that can be manufactured with reasonable ease – nominally 1mm and above.

Our mission [ongoing] is to investigate the performance of smaller bores, most notably bores in the order of 50 micron.

Results so far

Albeit early days, we have found good correlation between flow rates calculated using RW Miller critical flow function and the flow rates measured on test.

There are many factors to consider when determining the uncertainty budget for this project, and the very nature of manufacture currently dictates that we look at broad range of uncertainty (5% to 10%).

However, the theory is holding good and our objective is to utilise our finding for future flow measurement and flow control applications.