If we look at what is considered low flow measurement of air mass flow rate,  those applications ranging from 0 to 10 sccm up to 0 to 1000 slpm ranges, there is a right way and a wrong way to measure. It’s an inherent problem many of our customers face before they find the right […]

In this final post on pressure regulation and flow meters, I’d like to present a case study. A customer was convinced that our unit intermittently lost control for given flow rates. It turns out that as they increased flow rate, the outlet pressure of the regulator (inlet to the mass flow controller) was drooping below […]

Think about it. It’s pretty much impossible to make a controlled pressure drop without burning up some energy as heat. Therefore, the outlet pressure and flow rate cannot be linearly proportional at 1:1, but rather, must have some positive loss of X:1, where X is greater than 1. So, for a given regulator setpoint, the outlet pressure […]

If my previous post on droop, the least apparent pressure regulation issue, wasn’t enough of the low down for you, let me share some more about this common issue that arises with flowmeters. Droop is the difference between the outlet pressure at low inlet pressures and at high inlet pressures along the ‘operating range’ of the […]

If you’ve been reading my series on pressure regulation, you know my goal is to help you achieve the best possible gas mass flow control with your flowmeter. Previously, I’ve discussed undersizing and seat-drop lock. Now I want to move onto something that can really get you down – “droop.” Regulators may exhibit hysteresis, also known as droop. Droop is […]

Proper line regulation, be it supply pressure regulation, or back pressure regulation, is fundamentally key to a properly tuned flow system process. All instruments operate most accurately under steady-state conditions, so awareness of regulator behavior and proper tuning will save you time and money on avoiding waste during transient conditions. In my continuing tutorial on mass flow […]

In the world of mass flow control, it sometimes surprises me how often issues with mass flowmeters can be attributed to improper sizing of pressure regulators. But given all the intangibles with mass flow, I do get it. So, if you are building a flow system that requires precision gas mass flow control, this is the […]

I am always struck by the often beautiful world of flow measurement. Even though we design and manufacture precision flow meters and controllers for nearly any gas, liquid or steam flow application, the images linked below explain why there are so many different measurement technology solutions (Vortex, Thermal, Ultrasonic, Magnetic, Coriolis…etc.) to handle the variety of fluid flow applications […]

Meet the MFC we proudly call “Hammer-Trak”… What if you require very low-pressure drop across your mass flow controller and need to control higher flows? Case in point: I had a customer asked me to design an MFC to handle medium-to-high flows (100-500 slpm Air), with at MOST 1.0 PSIG delta across the unit.  To solve this difficult problem and […]