Company Profile

Gas Mass Flow Controllers for Automated High-Speed Gas Blending and Delivery Sinks

Quick Answer: Silver Instruments supplies gas mass flow controllers and automated gas blending panels for high-speed gas mixing and delivery to process sinks. You can expect accuracy of ±0.5% of full scale, response time under 500 ms, and control outputs including 4-20 mA, 0 to 5 VDC, and Modbus RTU. Send us your gas types, pressure in bar, pipe size in DN or inches, and target flow range for a quote.

Why High-Speed Gas Blending Needs a Mass Flow Controller

A mass flow controller measures gas by thermal mass, not by volume. Volume changes with temperature and pressure. Mass flow control keeps the gas ratio stable even when the line pressure moves. That matters for gas blending systems that feed multiple delivery sinks across a plant. We see this in food packaging, laser cutting, and semiconductor process gas panels. Each gas line uses one MFC. The controller compares the setpoint with the measured mass flow. It drives a control valve to hold the flow. Response time under 500 ms is common for high-speed loops. Some systems settle within 1 second. This keeps the mixed gas composition stable during rapid load changes.

Typical Gas Blending and Delivery Sink Configurations

A gas blending panel may combine nitrogen and carbon dioxide for food packaging. Another panel might mix argon and carbon dioxide for welding gas. A delivery sink is the point where mixed gas is consumed, such as a test bench, a burner, or a packaging machine. Silver Instruments configures each channel with a thermal mass flow controller, a filter, a check valve, and a pressure transmitter. The gas header can be DN15 or DN25. We often use 1/4 inch or 3/8 inch compression fittings for low flow. For higher flow up to 200 slm, use 1/2 inch or DN15 connections. The controller accepts 24 VDC power. Control signals can be 4-20 mA, 0 to 5 VDC, or Modbus RTU over RS485. Accuracy is typically ±0.5% of full scale plus ±0.1% of reading for some gases.

Gas Types and Flow Ranges

Do not assume one controller fits all gases. Calibration for methane, hydrogen, nitrogen, argon, oxygen, and carbon dioxide is common. Each gas has a different thermal conductivity and specific heat. Silver Instruments calibrates every MFC on a primary standard flow bench. We request your gas mixture and expected concentration. For low flow, the SI-MFC-100 series covers 0 to 20 sccm and 0 to 50 slm. For high flow headers, the SI-MFC-500 series covers 0 to 100 slm and 0 to 500 slm. If you need 0 to 1000 slm, we add a larger laminar flow element. This is not a catalog item for every range. We build it against your process data.

Delivery Sink Pressure Control and Safety

Each delivery sink should have a local pressure gauge and a pressure transmitter. Some sinks need back pressure control. A gas mixing panel without a pressure control loop may drift when downstream equipment opens or closes. Add a buffer tank of 20 to 50 liters for high-speed gas delivery to absorb flow surges. Use stainless steel 316L wetted parts for corrosive gas mixtures. For solvent vapor or flammable gas blending in chemical plants, Silver Instruments can supply ATEX Zone 1 approved enclosures. Leak test each panel with helium. A typical acceptance limit is 1 x 10 to the power of minus 9 atm cc per second. That number matters for gas safety.

Customer Example: Food Packaging Gas Blend in Vietnam

Last year a packaging line in Ho Chi Minh City asked us for a gas mixing system. They needed 70 percent nitrogen and 30 percent carbon dioxide for modified atmosphere packaging. Total flow was 180 slm at 2.5 bar. We supplied two thermal mass flow controllers, one for N2 and one for CO2. The controllers used 4-20 mA signals and Modbus RTU for the PLC. After installation the customer measured oxygen residue below 0.5 percent. The system has run for 14 mon