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『Influx Flow Meter: Catalog Overview of Variable Area Industrial Rotameters and Flow Switches』Related information(v cone flow meter|rotary gas meter|gallon meter|gear meter|metal tube rotameter|glass tube rotameter|nutating disk meter|transit time ultrasonic flow meter|wedge flow meter|pd meters|hydraulic flow meter|ultrasonic water flow meter|water flow meter|air flow meter|magnetic water flow meter|oxygen flow meter|gas flow meter|argon flow meter|air velocity meter|gasoline flow meter|fuel flow meter|ultrasonic water meter|digital water meter|nitrogen flow meter|solid flow meter|Oxygen tank flow meter|digital water flow meter|diesel fuel flow meter|steam flow meter|02 flow meter|compressed air flow meter|oil flow meter|liquid flow meter)
Influx Flow Meter: Catalog Overview of Variable Area Industrial Rotameters and Flow Switches
Quick Answer: The Influx flow meter catalog covers metal tube and glass tube variable area rotameters plus flow switches for alarm and control loops. These meters fit low viscosity liquids, gases, and light slurries from DN15 to DN150. Engineers in water plants, chemical skids, and food processing often choose them because the installation is simple and the mechanical display does not need loop power.
Silver Automation Instruments supplies Influx variable area flow meters from stock in Nanjing and from partner warehouses in Southeast Asia and the Middle East. The catalog is built for industrial users who need a short lead time and a clear quote. But we have seen many sites replace complex electronic meters with a basic rotameter and a separate flow switch when the process only needs local indication plus one alarm contact.
What the Catalog Covers
The Influx flow meter catalog is split into three groups. First are the glass tube rotameters for low pressure water and air service. Second are the metal tube rotameters for higher pressure and temperature. Third are the flow switches that trip a relay at a set flow rate. Most models come with threaded, flanged, or tri-clamp connections. Standard sizes start at DN15 and go to DN150. Smaller DN10 and DN8 bodies are available for dosing skids and laboratory test benches.
Metal Tube Rotameters for Industrial Lines
Metal tube variable area rotameters are the main workhorse in this catalog. A typical unit has a stainless steel body, a float, and a magnetic indicator. The float position is transferred to the indicator without a glass sight tube. That makes the meter suitable for dark liquids, hot water, or corrosive chemicals where a glass tube would be unsafe. Standard accuracy is 1.6 percent of full scale. Optional two-wire 4-20 mA HART transmitters give remote rate or total flow output.
Process conditions matter. We quote metal tube rotameters up to 40 bar and 150 °C as standard. In practice, most customer enquiries fall between 2 bar and 10 bar. A water treatment contractor in the Philippines recently ordered DN25 metal tube rotameters for sodium hypochlorite dosing. The process temperature was 35 °C and pressure was 3 bar. We selected a 316L body with PTFE lining and a local indicator.
Glass Tube Rotameters for Water and Air
Glass tube rotameters are the lowest cost option for clean water, air, nitrogen, and other transparent fluids. The catalog includes 100 mm, 150 mm, and 250 mm tube lengths. Flow ranges start from a few liters per hour for laboratory use. A standard glass tube rotameter with a valve handles up to 10 bar at 60 °C. For outdoor installations, we suggest an acrylic shield or a stainless steel guard.
One thing to remember is that glass tube meters do not forgive thermal shock. Do not install one directly after a steam line. We have seen cracked tubes on customer sites when an operator opened a bypass too fast. A simple isolation valve pair solves most of these problems.
Flow Switches for Alarm and Control
The Influx catalog also lists variable area flow meters with built in or separate flow switches. These switches send a dry contact output when flow rises or falls past a set point. The contact rating is usually 250 VAC at 5 A. That is enough for a small pump interlock, a solenoid valve, or a PLC input. Adjustable models use a metal reed switch that slides along the meter body. Fixed set point models are cheaper and easier to install.
We often recommend a flow switch for cooling water lines on compressors and furnaces. A steel plant in Vietnam bought 40 flow switches from our stock last year. They needed a simple way to prove that cooling water was moving before starting a heat exchanger. The switch was set at 10 liters per minute and wired to the control p
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Key Parameters for a Quote
Send us your pressure in bar, temperature in °C, pipe size in DN, and flow range in l/h, kg/h, or Nm3/h. For gas service, include the working pressure and temperature because actual gas volume changes with density. For liquid service, note the viscosity. Most variable area rotameters work well from 0.5 cP to 200 cP. Above 200 cP, we may suggest an oval gear flow meter instead.
Here is the thing. The same DN50 meter can cover many flow ranges by changing the float material and the cone profile. That is why copying a model number from an old purchase order can cause sizing errors. We prefer to check the range against the current process data before confirming a quote.
Industry Use Cases
A paint manufacturer in Malaysia uses metal tube rotameters on solvent transfer lines. The solvents have a viscosity around 2 cP and a density close to 0.8 kg per liter. The customer chose PTFE lined meters with 4-20 mA output for batch records. A fishmeal plant in Peru uses glass tube rotameters for compressed air injection. A water utility in Saudi Arabia installed flow switches on filter backwash lines. These are all standard applications we have handled through the same catalog.
Marine and offshore users often request stainless steel flow switches with weatherproof enclosures. For those jobs we confirm the protection class, cable entry, and any classification requirement. ATEX Zone 1 or Zone 2 options are available on many metal tube models. The delivery time is longer than standard because of certification paperwork.
Pricing and Lead Time
Glass tube rotameters are usually the cheapest option and many DN15 to DN50 sizes ship from stock. Metal tube rotameters with stainless steel bodies take 3 to 15 working days depending on the connection and the scale. Flow switches with explosion proof housings may take 10 to 20 working days. We give a firm quotation with freight cost to Southeast Asia, Oceania, Latin America, Africa, or the Middle East after we check the technical data.
You can contact Silver Automation Instruments by phone at +86-25-68650347 or by WhatsApp at +86-25-52155837. WeChat is +86 15365082610. Tell us the fluid, flow range, pipe size, and pressure. We will reply with a catalog page and a one to one recommendation. So do not send a long email without process data. The technical review goes faster when we have the actual values.
FAQ
Are Influx variable area rotameters suitable for dirty water? Glass tube meters can clog or cloud the viewing window. Metal tube rotameters are better for dirty water because there is no glass tube. Use a filter upstream if the solids load is high.
Can I use a rotameter for gas flow measurement? Yes. Specify the gas name, operating pressure, and temperature. We size gas rotameters in Nm3/h or l/min at working conditions.
Do the flow switches need a separate power supply? No. Basic mechanical flow switches work as dry contacts. Only models with electronic transmitters need loop power for the 4-20 mA signal.
What is the normal accuracy of a variable area rotameter? Glass tube models are about 2.5 percent of full scale. Metal tube models are about 1.6 percent of full scale. They are not comparable to Coriolis meters but they are good for local indication and alarm duties.
Can Silver Automation Instruments supply ATEX or IECEx models? Yes for many metal tube rotameters and flow switches. State the zone, gas group, and temperature class in your enquiry.
Silver Automation Instruments supplies the full Influx variable area flow meter catalog for industrial projects and OEM skids. Ask for DN15 to DN150 rotameters, PTFE lined bodies, 4-20 mA HART transmitters, and flow switches with dry contacts. Our sales engineers are available on +86-25-68650347, WhatsApp +86-25-52155837, and WeChat +86 15365082610.