Current position > Product detail
『Flow Meter Types and Principles: Volumetric vs Mass Sensing Basics』Related information(clamp on meter|electromagnetic meter|venturi meterrotameter|orifice meter|ultrasonic flow meter|mass flow meter|coriolis mass flow meter|coriolis flow meter|magnetic flow meter|magmeter flow meter|magflow flow meter|mag meter flow meter|electromagnetic flow meter|vortex flow meter|turbine flow meter|thermal mass flow meter|thermal flow meter|rotameter flow meter)
Flow Meter Types and Principles: Volumetric vs Mass Sensing Basics
Quick Answer: Volumetric flow meters count the actual volume of fluid that passes through the flow chamber. They work best for viscous liquids like heavy fuel oil, diesel, glucose syrup, and polymer melts. Mass flow meters measure mass flow rate directly and ignore changes in temperature, pressure, or density, which is why Coriolis and thermal mass sensors dominate custody transfer and reactor feed applications. Silver Automation Instruments stocks both technologies and ships them from China to end users across Southeast Asia, Oceania, the Middle East, Africa, and Latin America.What Is a Volumetric Flow MeterIn the simplest terms, a volumetric flow meter divides a flowing stream into fixed, countable volumes. Each pocket fills and empties, and the meter counts the cycles. Oval gear meters and gear flow meters are common positive displacement devices in this family. Because they trap fluid physically, they deliver strong repeatability on liquids that have a viscosity above 5 cP. Many engineers skip high-maintenance turbine meters on dirty oil and go straight to an oval gear meter just to get a stable 0.5% reading repeat hour after hour.We have seen this on customer sites many times. In 2024, a paint manufacturer in Ho Chi Minh City replaced three mechanical turbine meters with our DN25 oval gear flow meter. The fluid was a solvent-based primer with viscosity around 180 cP at 30 degrees C. The old turbine output swung by 3 percent when the temperature shifted by only 5 degrees C in the morning. The oval gear meter stamped out that error. The plant now runs batch dosing directly from a 4-20 mA HART signal wired into a Siemens PLC. No more manual correction tables.Common applications for volumetric meters are fuel oil consumption monitoring on ships, edible oil blending in food plants, and diesel transfer in mining sites. Silver Automation Instruments offers oval gear flow meters from DN6 up to DN200 in cast iron, SS304, and SS316. For a gold mine in Ghana, we supplied a DN40 meter that runs 24/7 on heavy lubricant oil at 80 degrees C and 16 bar. It has a local totalizer and an active 4-20 mA pulse output. Total delivered cost was about one-third that of a comparable Coriolis meter, which is exactly why the procurement manager chose this route.How Mass Flow Meters WorkA mass flow meter reads the true mass moving through the sensor, normally in kg/h or t/h. The two main types we supply are Coriolis and thermal mass. Coriolis meters use vibrating tubes and measure phase shift to get mass flow and density in one go. Thermal mass meters work with heated sensors and measure the cooling effect of gas molecules, giving direct mass flow of air, natural gas, biogas, or argon without any pressure or temperature compensation needed in the PLC.Here is the thing. When you buy a Coriolis mass flow meter from Silver Automation Instruments, you get a sensor that typically includes an integrated PT100 for temperature, a density output, and a standard 4-20 mA HART or Modbus RTU interface. A DN15 unit weighs only 9 kg but can measure from 0.1 kg/h up to 1000 kg/h with ±0.1% of rate accuracy. That same meter handles viscous adhesive, supercritical CO2, and demineralised water without any K-factor change. One chemical terminal in Port of Tanjung Priok, Indonesia, installed six of our DN25 Coriolis meters on an additives loading skid. They needed ATEX Zone 1 certification and accurate mass totals for tax invoices. The meters delivered end-of-day batch totals that matched the weighbridge reading within 0.2%, which satisfied the local metrology office on the first audit.Thermal mass flow meters from Silver Automation Instruments target gas and compressed air networks. They are compact, have negligible pressure drop, and offer a direct mass output in kg/h or Nm³/h. A food-grade nitrogen blanketing line in a Kenya coffee factory uses our inline thermal mass meter with a local OLED display and RS485 output. The operator reads mass flow directly and adjusts the nitrogen valve without any manual conversion charts.Volumetric vs Mass: Key Differences That Affect Your BillIn practice, the biggest difference hits you during temperature and pressure swings. A volumetric meter measures volume at actual conditions. If the fluid density changes by 2 percent, the mass inside that volume changes by the same 2 percent, but the meter still reports the same litres. A mass meter does not care. It reports the real mass that moves. When a buyer in Dubai pays for a truckload of palm oil by mass, a magnetic flow meter or an oval gear meter alone is not enough. You need a Coriolis mass meter, or at minimum a volumetric meter combined with a densitometer and a flow computer.Viscosity is the other filter. Positive displacement oval gear meters love high viscosity. They even increase accuracy slightly as viscosity climbs. A standard oval gear meter on diesel with 4 cP might give 0.5% accuracy. On heavy fuel oil at 180 cP, the same meter easily holds 0.3%. Coriolis meters also handle viscosity well but carry a
Contact Silver Automation Instruments todayEmail: sales@sil