Current position > Contact Us
Quick Answer: Silver Automation Instruments is a low flow flow meter manufacturer and supplier for Southeast Asia, Oceania, Latin America, Africa, and the Middle East. Low flow meters and low flow sensors from our range measure liquids and gases from DN3 to DN25, with starting points near 0.01 kg/h for Coriolis mass flow meters and 0.05 L/h for oval gear flow meters. Send us your flow range, pipe size DN, pressure bar, temperature °C, and fluid name for a fixed quotation.
In most process plants, low flow means less than 100 kg/h for liquids and less than 50 slpm for gases. This range is common in chemical dosing, pilot reactor feed, fuel oil supply to burners, and seal water lines. The pipe size is usually DN3 to DN15. Some skid builders ask us about additive injection rates from 0.5 L/h to 5 L/h. The fluid can be as thin as water or as thick as 500 cP oil.
Standard electromagnetic flow meters struggle below 0.1 m/s flow velocity. The signal becomes noisy and the output drifts. Vortex flow meters stop producing reliable shedding at low Reynolds numbers. Turbine flow meters add pressure drop and can stall in viscous liquids. That is why a low flow meter with a small bore and a direct mass or positive displacement principle is more stable.
Our Coriolis mass flow meters measure mass directly. You do not need separate temperature compensation for mass flow. A Silver Instruments Coriolis flow meter with DN3 or DN6 process connections can measure 0.01 kg/h to 600 kg/h. Accuracy is around ±0.1 percent of reading for liquids. Wetted parts include 316L stainless steel and Hastelloy C22 options. Outputs are 4-20 mA HART, pulse, and RS485 Modbus. This meter is often used for catalyst injection in polymerization lines, flavor dosing in beverage plants, and methanol feed in biodiesel pilot plants.
For gas lines under 50 slpm, thermal mass flow sensors respond faster than differential pressure devices. Silver Instruments supplies inline thermal mass flow meters with DN4 to DN20 connections. Typical accuracy is ±1 percent of full scale. The sensor uses a heated RTD and a reference RTD. It works with air, nitrogen, natural gas, and clean biogas. We have seen units installed on burner test rigs in Saudi Arabia and on laboratory gas blending skids in Malaysia. The output is normally 4-20 mA with optional RS485 Modbus.
Oval gear flow meters are a practical choice for diesel, lube oil, fuel oil, and some chemicals. The smallest body uses DN4 or DN6 connections. It can measure from 0.05 L/h up to about 100 L/h. Viscosity above 5 cP improves sealing between the oval gears. A paint manufacturer in Vietnam needed to dose 2 L/h of solvent into a mixing vessel. A DN4 oval gear meter with 4-20 mA output solved the issue. The meter body was 316L stainless steel with PTFE seals.
An electromagnetic flow meter works when the liquid conductivity is above 5 µS/cm. For low flow water lines, we use DN2 to DN15 sensors with PTFE or PFA liners. The minimum flow velocity is about 0.05 m/s. This works for water treatment plants that inject flocculant or coagulant. A customer in Australia asked for a DN10 electromagnetic flow meter to measure 0.8 L/min of sodium hydroxide solution. The meter had tantalum electrodes and 4-20 mA HART output. The reading stayed stable because the line was always full and back pressure was kept above 0.2 bar.
Ultrasonic flow meters are not the first choice for very low flow. They need clean liquid and a minimum flow velocity around 0.1 m/s in small pipe sizes. A DN15 inline ultrasonic meter can measure water from about 0.5 L/min to 20 L/min. This suits RO permeate lines, cooling water branches, and small distribution pipes. We usually recommend ultrasonic only when the fluid is non-conductive or the customer wants no moving parts and no pressure drop.
In practice, most engineers skip the long catalog search and send us four things. Send the flow range with units such as kg/h, L/h, or slpm. Send the fluid name and viscosity if known. Send the pipe size DN and connection type such as threaded G1/8 or compression fitting. Send the pressure bar and temperature °C. We respond with a recommended model, accuracy, wetted parts, and price. Contact Silver Automation Instruments: Tel: +86-25-68650347, WhatsApp: +86-25-52155837, WeChat: +86 15365082610.
Q: What is the lowest liquid flow rate a Coriolis meter can measure?
A: A DN3 Coriolis mass flow meter from Silver Instruments can measure 0.01 kg/h for water-like liquids. Dense or viscous liquids may allow even lower mass flow detection, but pressure drop will increase.
Q: Can you measure low gas flow without temperature and pressure compensation?
A: A thermal mass flow sensor measures mass flow directly for most clean gases. It does not need a separate pressure transducer or temperature compensation. For wet gas or large pipe sizes, check the process conditions first.
Q: Which low flow meter works best for diesel or heavy oil?
A: An oval gear flow meter with DN4 or DN6 connections is usually the most practical choice. It handles viscosity from 5 cP to over 1000 cP and gives a pulse or 4-20 mA output.
Q: Do electromagnetic flow meters work at low flow rates?
A: Yes, if the liquid conductivity is above 5 µS/cm and the pipe stays full. A DN10 electromagnetic meter can measure 0.05 m/s and above. Below that velocity the signal stability depends on installation and grounding.
Q: What details should I send for a fast quotation?
A: Send flow range in kg/h, L/h, or slpm, fluid name, viscosity, pipe size DN, connection type, pressure bar, temperature °C, and power supply. This helps our engineers choose the right low flow sensor and quote within one business day.
