What’s A Mass Flow Controller?

mass flow controllers from Metlan Instruments

Measuring and regulating gas or liquid flow with precision is fundamental in industries ranging from semiconductors to biotech. Among the most reliable instruments for this task is the Mass Flow Controller (MFC). This guide will walk you through what MFCs are, their major types and operational principles, their applications.

What Is a Mass Flow Controller?

A Mass Flow Controller (MFC) is a fluid control device designed to measure and regulate flow by mass, not just volume. Unlike traditional mass flow meters, MFCs contain an internal valve mechanism and a control loop that maintains flow at a specific setpoint. This makes them ideal for systems that require precise, stable delivery of fluids under varied conditions.

Key characteristics of MFCs:

  • Measures and actively controls flow
  • Operates with high repeatability and accuracy
  • Suitable for very low flow rates, including SCCM (standard cubic centimeters per minute)
  • Offers digital and analog communication for automation integration

How Does Mass Flow Controllers Work

mass flow controller working principle

The main components of mass flow controllers include a flow sensor, a control valve, and an electronic controller. The flow sensor continuously measures the actual mass flow of the fluid passing through the device, often using thermal or differential pressure principles. This measurement is sent as a signal to the electronic controller, which compares it to a user-set target flow rate.

If the measured flow deviates from the target, the controller automatically adjusts the control valve to increase or decrease the flow, maintaining a stable and accurate output. This feedback loop operates in real time, allowing the MFC to respond quickly to changes in pressure, temperature, or other process conditions.

Types of Mass Flow Controllers

Thermal Mass Flow Controllers

Nasıl Çalışıyorlar? Measure the heat transfer away from a heated sensor element; the heat loss relates directly to the mass flow. Here’s a case study of thermal mass flow controller.

En iyisi: Clean, dry gases at low flow.

Artıları:

  • Compact, highly sensitive, no moving parts
  • Excellent accuracy in low-flow measurements

Eksiler:

  • Sensitive to gas composition and moisture
  • Requires recalibration for different gases
Termal Gaz Kütle Akış Ölçer Kontrolörü

Thermal Gas Mass Flow Controller MTL20FD

  1.  Düşük akışlı gaz ölçümü için tasarlanmıştır.
  2. Kısma Oranı: Dijital kütle akış kontrolörü için 50:1; dijital kütle akış ölçer için 100:1.
  3. Tepki Süresi: kütle akış kontrolörü <0,2s; kütle akış ölçer <0,1s
  4. Akış hızını düzenlemek için entegre PID kontrolörü
  5. Doğrudan kütle akış hızı ölçümü, otomatik sıcaklık kompanzasyonu
  6. Dokunulabilir ekran
  7. Çeşitli yüksek ve düşük basınçlı boru hatları için uygundur.

Differential Pressure (DP)-Based Mass Flow Controllers

Nasıl Çalışıyorlar? Monitor pressure differences across an internal orifice or laminar flow element; modulate flow with a control valve.

En iyisi: Gases, steam, and sometimes liquids in applications requiring broader applicability.

Artıları:

  • More robust across environmental variations
  • Suitable for multi-fluid applications

Eksiler:

  • Less accuracy at very low flows
Differential Pressure Gas Mass Flow Meter Controller

Differential Pressure Mass Flow Controller MTL20FC

  1.  Düşük akışlı sıvı/gaz/buhar ölçümü için tasarlanmıştır.
  2. Kısma Oranı: Dijital kütle akış kontrolörü için 50:1; dijital kütle akış ölçer için 100:1.
  3. Tepki Süresi: kütle akış kontrolörü <0,2s; kütle akış ölçer <0,1s
  4. Akış hızını düzenlemek için entegre PID kontrolörü
  5. Doğrudan kütle akış hızı ölçümü, otomatik sıcaklık kompanzasyonu
  6. Dokunulabilir ekran
  7. Ön ısıtma gerektirmez, ölçüm sırasında yanıt gecikmesi olmaz.

Coriolis Mass Flow Controllers

Nasıl Çalışıyorlar? Utilize vibrating tubes to measure mass flow directly through the Coriolis effect—a true mass measurement independent of temperature or pressure variations.

En iyisi: All fluids—including mixtures and viscous liquids.

Artıları:

  • Exceptional accuracy (±0.1–0.2%)
  • Measures mass flow, density, and temperature
  • Requires minimal recalibration for composition shifts

Eksiler:

  • Daha yüksek maliyet
Coriolis Mass Flow Meter Controller

Coriolis Mass Flow Controller MTL20FE

  • MTL20FE measures a wide range of fluids, such as lubricating oil, liquid nitrogen and other high-density fluids can also be accurately measured.
  • Yüksek hassasiyet, iyi tekrarlanabilirlik. Sıvılar için ölçüm doğruluğu ± 0,25%'ye ulaşabilir; gazlar için ölçüm doğruluğu ± 0,5%'ye ulaşabilir.
  • Aşırı çevre koşullarına dayanabilen yüksek güvenilirlik ve kararlılık

Applications of Mass Flow Controllers

Semiconductor and Electronics

Precise gas control is vital in deposition and etching processes (e.g., CVD, PVD).

Laboratories and Research

Essential for exact gas delivery in chemical, physical, or biological experiments.

Biotech and Medical

Used in cell culture control, respiratory gas management, and dosing in medical devices.

Energy & Environmental Monitoring

Crucial for hydrogen fuel cell testing, emissions control, and biogas flow regulation.

Industrial Processing

Integral in welding, metal treatments, and chemical mixing where tight control of gas flow is mandatory.

Mass Flow Controllers remain essential tools across critical industries requiring precise fluid delivery. From thermal MFCs suited for cost-effective gas control, to Coriolis controllers offering top-tier accuracy across all media, and DP MFCs for industrial resilience—each technology brings unique benefits.

If your operation demands compact, ultra-low flow control with fast stabilization, Metlan Instruments’ MFCs are a compelling solution—offering multi-principle versatility, excellent accuracy, and modular designs that seamlessly integrate into high-precision applications.

Here’re some more posts about Mass Flow Controller: