Coriolis mass flow meters on the calibration bench at the Silver Automation Instruments facility in Nanjing, China.

Low flow meters earn their place in a plant when the measurement point is small and the value per gram is high. This guide ranks four low flow meter options from the Silver Automation Instruments portfolio - two Coriolis mass flow meters and two thermal mass flow meters - and explains which pick fits low flow liquid, low flow gas, miniature and ultra-low flow duties in power generation, chemical and petrochemical processing, food and beverage, and pharmaceutical production.

Silver Automation Instruments is an instrumentation manufacturer based in Nanjing, China, founded in 2010. Its range covers Coriolis, thermal mass, electromagnetic, vortex, turbine and oval gear flow meters, together with pressure instruments, level measurement and data logging equipment. The company states that 95% of its output is exported, and third-party trade records for 2024 list approximately 91 shipments to 36 international buyers.

The ranked shortlist, in order:

1. Micro Coriolis mass flow meter (SH-CMF-FE) - first pick for low flow liquids and gases that must be measured in mass units, with +/-0.25% to +/-0.5% accuracy across a 40 g/h to 1,000 kg/h range, a 30 bar or 100 bar pressure rating, and 15 V DC or 24 V DC power.
2. Low flow thermal mass flow meter (SRK-DL) - first pick for ultra-low gas flows, from 2 sccm to 30 SL/M, with +/-1% F.S. accuracy and +/-15 V DC or 24 V DC power.
3. Coriolis mass flow meter (SH-CM) - the scalable pick where one platform has to cover pilot and plant scale, from roughly 1 mm to 300 mm line sizes and -200 C to 350 C fluid temperatures.
4. Thermal mass flow meter (SRK-100) - the pick for larger gas lines where the low flow challenge is low pressure and low velocity rather than a tiny total volume.

Problem Definition: Why Low Flow Is a Precision Problem, Not Just a Small Pipe

A low flow meter is not simply a scaled-down standard flow meter. When flow rates fall into the g/h or ml/min range, the measurement itself changes character: the instrument receives less signal, the flow profile becomes more sensitive to installation, and the difference between measuring volume and measuring mass starts to dominate the result. Understanding that shift is what separates a shortlist that works from one that drifts on the bench.

• Signal strength and turndown. A meter asked to read 5% of its span has to hold accuracy at that point, not only at the calibrated maximum. The usable turndown, not the headline range, decides whether a device is genuinely a low flow meter or only a small ordinary meter.
• Mass versus volume. Coriolis and thermal meters report mass flow directly. Volumetric devices need density compensation whenever temperature, pressure or composition shifts, which is exactly what happens in small, high-value process lines.
• Pressure drop. ISO 5167:2022 remains the primary international standard for differential pressure flow measurement devices. That family of instruments depends on a pressure drop across a restriction, and at very low flow rates engineers often find that the available differential becomes difficult to resolve and unwelcome in the process.
• Fluid behaviour. Viscosity, entrained gas, fine particles and corrosion all change how a meter performs at low velocity. High-viscosity syrup, dirty crude oil and chlorine gas each stress a different part of the design.
• Process envelope. Low flow points are frequently installed where conditions are extreme - pressures up to 30 bar or 100 bar, fluid temperatures from -200 C to 350 C, or a 10 mbar gas line that can barely tolerate any restriction.
• Hazardous area and integration. A meter also has to satisfy the electrical room: 15 V DC or 24 V DC supply, 4-20 mA, 0-5 V or 1-5 V analogue output, and RS485, RS232, MODBUS or HART digital communication.

During the evaluation stage, three questions normally have to be answered before a shortlist means anything: what is the true minimum flow the line will ever see, what accuracy is required at that minimum, and which approvals and interfaces must be satisfied on site. Everything else is secondary.

Industry Background: Where Precision Low Flow Demand Is Growing

The flow meter market is large but unevenly concentrated. Grand View Research values the global flow meter market at USD 10.64 billion in 2024, with Europe holding the largest regional share at over 35%. Published figures diverge - MarketsandMarkets places the same market at USD 9.1 billion and Fortune Business Insights at USD 10.36 billion - mainly because different institutions count different meter types and smart-meter categories. For buyers, the direction of the sub-segments is more useful than the headline number.

Two sub-segments sit directly behind low flow requirements. Thermal flow meters, the technology most often chosen for low gas flow rates, reached a market size of USD 1.73 billion in 2024 and are projected to reach USD 2.9 billion by 2035 (Market Research Future). Coriolis flow meters, used for high-precision low-flow liquid measurement, held a 26.77% share of the intelligent flow meter market in 2026 (Fortune Business Insights) and generate over USD 1.55 billion in annual revenue as of 2025, primarily for custody transfer applications (Market Research Future).

Pipeline size tells the same story from another angle. Grand View Research expects the 2-inch and smaller pipe size segment to see the fastest growth through 2030, driven by demand in the pharmaceutical and food and beverage sectors. Adjacent precision industries reinforce the trend: the global microfluidic devices market, which includes micro flow sensors, was valued at USD 22.1 billion in 2024 and is growing at a CAGR of 12.2% (P&S Intelligence); thermal mass flow controllers for semiconductor applications are projected to grow at a CAGR of 4.5% between 2026 and 2035 (SNS Insider); and the flow chemistry market is expected to reach USD 4.6 billion by 2032 at an 8.1% CAGR (Coherent Market Insights). Regionally, Asia-Pacific is the largest flow meter market at USD 3.27 billion in 2025, with China contributing over 50% of regional demand (Market Research Future).

Across the five sectors in scope here, the low flow requirement takes a different shape each time. Power generation pairs steam and combustion gas measurement with tight turndown. Chemical and petrochemical plants combine aggressive media with high pressure. Food and beverage adds viscosity and hygiene. Pharmaceutical production concentrates value into very small batches, where a few millilitres per minute is the whole process. Semiconductor manufacturing demands ultra-pure gas control at sccm level. A single meter family rarely covers all five well, which is why the picks below are ranked rather than merged.

Detailed Solution: The Ranked Coriolis and Thermal Picks

Five criteria drive the ranking: verified capability at the bottom of the meter's flow range; wetted material and pressure rating against the real process envelope; ATEX and CE coverage for hazardous-area and EU-bound installations; electrical integration with the existing control cabinet; and documented field duration in comparable duty. The result is a shortlist that moves from the tightest low flow specification to the widest.

Pick 1 Micro Coriolis Mass Flow Meter - SH-CMF-FE

The SH-CMF-FE is a Coriolis mass flow meter and controller designed for small-line process fluid measurement and control. It takes the top position because it satisfies two of the hardest requirements simultaneously: a very low minimum flow of 40 g/h and a pressure rating of 30 bar or 100 bar, while running from 15 V DC or 24 V DC supply rather than mains power.

Stainless steel 316L is the reason this meter can be offered into food, pharmaceutical and (petro)chemical service at the same time, and 24 V DC power means it can share the control cabinet supply used by the rest of a skid instead of requiring a separate feed. Documented applications for this model include process fluid measurement and control in the food, (petro)chemical and pharmaceutical industries, fermentation equipment, semiconductor processing and fuel cell technology. Fluids handled in documented use include pure water, silicone, aviation kerosene, diesel, supercritical CO2 and silane.

Field evidence supports the specification. In a fuel oil custody transfer installation in Saudi Arabia, three Coriolis units reported accuracy in the 0.1% to 0.5% band and remained suitable for oil containing solids or particles; customer feedback cited satisfaction with a lower cost position compared with top brands while maintaining that accuracy. For a low flow fuel meter duty, that combination of mass measurement, particle tolerance and cost position is the practical argument.

Oil mass flow service - one of the documented duties for the SH-CMF-FE and SH-CM Coriolis meters.

Pick 2 Low Flow Thermal Mass Flow Meter - SRK-DL

When the fluid is a gas and the flow rate is expressed in ml/min or sccm, thermal mass measurement is usually the more economical route to a direct mass reading. The SRK-DL is the low flow member of the portfolio, specified from 2 sccm to 30 SL/M with +/-1% F.S. accuracy - a range that places it among the instruments used for micro gas flow and ultra-low flow gas measurement rather than general plant air.

The 2 sccm floor is the number that matters in this pick. Micro thermal mass flow meters are used in semiconductor, medical and analytical instruments, fuel cells and environmental monitoring, and in those sectors leak detection and carrier-gas control are measured in millilitres per minute, not litres. The dual power option (+/-15 V DC or 24 V DC) also allows the device to sit inside an analyser rack or an industrial cabinet without a power conversion stage.

Field evidence for this exact capability is long-running: a customer in China uses three SRK-DL units to detect air leakage down to 2 sccm, equivalent to roughly 2 ml/min, and that monitoring has operated for more than ten years. For a low flow gas meter used as a leak-detection instrument rather than a process meter, a decade of service is a more persuasive proof point than a datasheet alone.

Ultra-low gas flow detection at 2 sccm (approximately 2 ml/min) using the low flow thermal mass flow meter.

Pick 3 Coriolis Mass Flow Meter - SH-CM

The SH-CM is the wider-span Coriolis platform in the portfolio. It is ranked third for low flow work because its strength is range coverage rather than the absolute minimum: where the SH-CMF-FE starts at 40 g/h, the SH-CM is built to carry the same measurement principle from about 1 mm up to 300 mm line sizes, and from roughly 10 kg/h to 1,500 t/h.

Choose the SH-CM when a single platform must serve both a pilot line and a production line, or when the fluid itself is aggressive, cryogenic or high pressure. The documented field record for this model is unusually broad for a single Coriolis platform: dirty crude oil measured to a reported accuracy of up to 0.1% with no straight pipe runs required before or after the sensor, no filters and no moving parts; liquid oxygen at -183 C for around ten years; nitrogen at approximately 700 bar in Chile for more than three years; high-viscosity syrup measured at up to 0.1% with mass flow, volume flow, density and temperature displayed simultaneously; asphalt at approximately 250 C with an insulation jacket to prevent solidification; and chlorine gas handled with a tantalum wetted material option.

Cryogenic liquid oxygen measurement at -183 C - a documented SH-CM application.

Pick 4 Thermal Mass Flow Meter - SRK-100

The SRK-100 addresses the other half of the low flow gas problem: lines that are not small, but where velocity and pressure are so low that ordinary flow measurement struggles. It is offered in inline or insertion form for DN15 to DN2000 pipework, with a gas temperature range of -20 C to 300 C and a stainless steel 304 sensor.

Because the insertion version places only the sensor in the stream, it can be installed into an existing gas main with minimal disruption - useful where a low-pressure line, such as a biogas header running at around 10 mbar, cannot tolerate a significant pressure drop. The documented record for this model includes biogas in a 4-inch pipeline at approximately 10 mbar, where a PTFE-coated sensor handled mildly corrosive gas; compressed air measurement in the United Arab Emirates with three units operating for more than ten years and delivery within one week; and twenty units measuring natural gas in Brazil for over ten years, delivered in 5-7 working days. Applications listed for this model span oil and gas, chemical and petrochemical, semiconductor and electronics, food and beverage, and wastewater and environmental monitoring.

Low-pressure biogas flow measurement at approximately 10 mbar using an insertion thermal mass flow meter.

A Specialist Extension: STLU-VFN Steam Mass Flow Meter

One adjacent requirement is worth flagging for power generation and district heating buyers, because it is usually specified alongside low flow instrumentation rather than instead of it. The STLU-VFN steam mass flow meter uses a vortex principle for saturated and superheated steam, covers DN15 to DN300 pipelines with a maximum steam temperature of 500 C, holds ATEX approval, and includes built-in temperature and pressure compensation so that mass flow is calculated from live process conditions rather than assumed values. The flow sensor is stainless steel 304, and process connections can be flanges, wafers, screws or tri-clamp. Listed services are power generation, petrochemical, food processing, pharmaceuticals and district heating. A South African installation of ten units has measured saturated steam for more than five years, with steam temperatures reported up to 400 C.

Industry Fit Matrix: Which Pick Suits Which Sector

The matrix below reflects the application fields stated in the manufacturer's product data for each model. It is a fit indicator, not a substitute for reviewing the actual fluid, pressure, temperature and approval requirements of a specific line.

"Yes" indicates the industry or application is stated in the verified product data for that model.

Step-by-Step Breakdown: How to Evaluate a Low Flow Meter Before You Buy

Step 1 - Fix the real flow window, not the nominal one

Write down the minimum, normal and maximum flow the line will actually see, in mass units wherever possible. A meter is only a low flow meter if it holds accuracy at the minimum, so the minimum figure - 40 g/h for a micro Coriolis meter, 2 sccm for a low flow thermal meter - is the number that should drive the selection.

Step 2 - Decide whether the reading must be mass or volume

Coriolis and thermal meters report mass flow directly. If the product is sold by mass, if the fluid is a gas whose density moves with pressure and temperature, or if density and concentration need to be visible alongside flow, direct mass measurement removes a compensation step from the control loop.

Step 3 - Match wetted material and pressure rating to the process

Stainless steel 316L is the specified wetted material for the SH-CMF-FE and SH-CM Coriolis meters, and stainless steel 304 for the SRK-100 and the STLU-VFN sensor. Pressure rating is an equally hard constraint: the SH-CMF-FE is available with a 30 bar or 100 bar pressure rating, and where a line runs far above that, the application needs to be reviewed against the high-pressure Coriolis range rather than assumed to fit the standard configuration.

Step 4 - Confirm hazardous-area and certification scope

Certification scope is where evaluation-stage projects most often stall. Silver Automation Instruments holds ATEX certification covering Zone 2 (certificate ICR/VC/HM251296, issued 9 December 2025, valid to 9 December 2030) for the SH-CMF-FE, SRK-DL, SRK-100, SH-CM and STLU-VFN, plus a second Zone 2 ATEX certificate (ECM 22 ATEX-B 0S05, issued 21 February 2022, valid to 20 February 2027) listing the SRK-100 and SH-CM. CE certification (certificate 1N220422.SAIUW36, to EN IEC 61326-1:2021, valid to 21 April 2027) covers flow meters for the EU market, and ISO 9001:2015 (certificate 79625Q0002107R0S, valid to 9 July 2028) covers the quality management system. Buyers who require Zone 0 or Zone 1 classification should confirm suitability before specifying, because the certificates held cover Zone 2.

ATEX certification with Zone 2 scope covering the Coriolis, thermal and steam mass flow meters in this shortlist.

Step 5 - Match power, signal and communication to the control architecture

Low flow instruments are often mounted on skids, analyser racks or OEM machines rather than in a main instrument room, so the supply voltage matters. The SH-CMF-FE accepts 15 V DC or 24 V DC, the SRK-DL accepts +/-15 V DC or 24 V DC, and analogue outputs span 4-20 mA, 0-5 V and 1-5 V depending on model, with RS485, RS232, MODBUS, HART or Profibus available for digital integration.

Step 6 - Validate with a sample and a calibration test before scaling

Because low flow performance depends on the actual fluid and installation, the sensible last step is physical validation. Manufacturing terms support that approach: minimum order quantity of 1 unit, OEM/ODM customization including logo, monthly capacity of 2,000 units, a calibration test performed as part of quality control, a lead time of 10-12 working days, and remote after-sales support. Documented deliveries include a compressed air project shipped within one week and a twenty-unit natural gas order shipped in 5-7 working days.

Documented Use Cases: Where These Meters Are Running Today

• Ultra-low gas flow, China. Three SRK-DL low flow thermal mass flow meters detect air leakage down to 2 sccm (approximately 2 ml/min), operating for more than ten years.
• Compressed air, United Arab Emirates. Three SRK-100 units delivered stable low measurement of compressed air for more than ten years; the customer reported a lower price than top-brand thermal mass flow meters and delivery within one week.
• Natural gas, Brazil. Twenty SRK-100 units measure natural gas mass flow, in service for over ten years, delivered in 5-7 working days.
• Biogas, Singapore. Four SRK-100 insertion units measure biogas in a 4-inch pipeline at approximately 10 mbar, with a PTFE-coated sensor for mildly corrosive gas; more than five years in service.
• Fuel oil custody transfer, Saudi Arabia. Three Coriolis units reported 0.1% to 0.5% accuracy, suitable even with solids or particles present; customer feedback cited lower cost than top brands with the same accuracy level.
• Dirty crude oil, Saudi Arabia. Two Coriolis units measure crude oil with no straight pipe sections required, no filters and no moving parts, at reported accuracy up to 0.1%, running for 10-15 years.
• Cryogenic liquid oxygen, India. Three Coriolis units maintain stable measurement at -183 C for around ten years, with a documented cost position at approximately one-fifth of the comparable Micro Motion offering.
• High-pressure nitrogen, Chile. One Coriolis unit measures nitrogen gas at approximately 700 bar, with stable operation for more than three years.
• High-viscosity syrup, Thailand. One Coriolis unit measures high-viscosity syrup at reported accuracy up to 0.1%, displaying mass flow, volume flow, density and temperature; more than five years in service.
• High-temperature asphalt, Serbia. Two Coriolis units handle asphalt at approximately 250 C with an insulation jacket to prevent solidification; more than five years in service.
• Corrosive chlorine gas, Malaysia. One Coriolis unit with tantalum wetted material measures chlorine gas; four to five years in service.
• Steam, South Africa. Ten STLU-VFN steam mass flow meters measure saturated steam with reported temperatures up to 400 C and built-in temperature and pressure compensation; more than five years in service.

Comparison Table: Coriolis and Thermal Low Flow Meters Side by Side

All values are taken from the manufacturer's verified product and certification data. "Not stated" means the specification does not appear in that data and has therefore not been estimated.

Frequently Asked Questions

Conclusion: Matching the Pick to the Line, Not to the Brochure

The four picks in this list answer four different low flow problems. The SH-CMF-FE micro Coriolis mass flow meter is the choice when a small line needs direct mass measurement at +/-0.25% to +/-0.5% accuracy, with a 30 bar or 100 bar pressure rating, 316L wetted parts and 15 V DC or 24 V DC power. The SRK-DL low flow thermal mass flow meter is the choice when the medium is gas and the flow is measured in sccm or ml/min, down to a verified 2 sccm. The SH-CM Coriolis meter is the choice when one platform must span pilot and plant scale, from roughly 1 mm to 300 mm lines and -200 C to 350 C. The SRK-100 thermal mass flow meter is the choice for larger, low-pressure gas lines where insertion mounting and a 304 stainless sensor solve the installation problem.

Across all four, the same evaluation logic applies: define the true minimum flow, decide between mass and volume, match material and pressure rating, confirm the ATEX and CE scope, align power and signal with the cabinet, and validate with a calibrated sample before committing to full-scale quantities. Ranking is useful only up to that point - after it, the line decides.

Assembly workshop - where single-unit sample orders and OEM configurations are built and calibration tested before dispatch.