The built-in orifice plate flowmeter is a special structure differential pressure flowmeter, also known as "embedded orifice plate", "integrated orifice plate" or "small flow orifice plate".

Main advantages:

• Solves the problem of small flow measurement: Specifically designed for small pipe diameters and low flow rates, it can measure extremely small gas flows (such as a few liters per minute) and liquid flows.
• Compact structure and easy installation: Integrated design, small in size and light in weight. It is usually directly connected to the pipeline through threads (such as G thread, NPT thread) or small flanges, without the need for complex flange pairs, pressure tapping valve groups, and long pressure guiding tubes, greatly simplifying the installation.
• Integrated high precision: When integrated with high-performance micro-differential pressure transmitters, due to the reduction of issues such as leakage, blockage, and response delay caused by pressure guiding tubes, the overall system accuracy and reliability are relatively high.
• Relatively small pressure loss: Although the orifice plate itself causes pressure loss, due to the optimized flow path in the integrated design, the overall pressure loss is usually smaller than that of traditional orifice plates installed on pipelines of the same diameter.
• Can measure dirty media (for some models): Some built-in orifice plate designs have detachable or self-cleaning structures, facilitating maintenance.

Typical application scenarios

• Laboratory and R&D testing: Gas and liquid flow measurement for small-scale experimental setups.
• Auxiliary flow paths in process industries:
  • Measurement of small flow rates of gases such as instrument air, purge gas, and protective gas.
  • Precise metering of chemical additives and injectants (e.g., scale inhibitors).
  • Monitoring of small flow rates in sampling, return, and discharge pipelines.
• Semiconductor and electronics industries: Precise flow control of specialty gases (e.g., SiH₄, NH₃).
• HVAC: Measurement of small flow rates of water in fan coil units, VAV variable air volume systems, etc.
• Energy management: Monitoring of steam or water consumption in small equipment and branch lines.

The built-in orifice plate flowmeter is a successful application and miniaturization and integration innovation of the standard orifice plate principle in the field of small flow and small pipe diameter.