Variable Area Flow Meters

Variable Area Flow meters, also known as Rotameters, are a simple and versatile method of flow measurement. It requires no power and has a visual indicator. It provides flow measurement of liquids, gases, and steam. A float rises inside a conically shaped glass tube as the flow increases, and the position of the float on a scale can be read off as the flow rate. Since this measuring method is purely mechanical, it is both simple and reliable.

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Vertical Pointer Variable Area Flowmeter | QTLZ

Vertical Pointer Variable Area Flowmeter - Overview

This Variable Area Flowmeter adopts advanced technology, without contact and no hysteresis detecting changes in the angles of the magnetic field of the magnetic sensor. It has a high-performance MCU. The LCD displays the instantaneous flow, total flow, loop current, environmental temperature, and damping time. Optional 4~20mA transmission (with HART communication), pulse output, and high and low limit alarm output function. This type of intelligent signal transmitter has high precision and reliability. Suitable for small and medium flow measurement of single-phase liquid or gas with small and medium pipe diameters. Applications include Water Treatment, Food Industry, Pharmaceuticals, Petrochemicals, Paper and Chemicals.

Vertical Pointer Variable Area Flowmeter - Features
- Range ratio: 10:1 (Special type 20:1)
- Accuracy class: 2.5 (Special type 1.5% or 1.0%)
- Working pressure: DN15~DN50 PN16 (Special type 2.5MPa)
- Medium temperature: Normalised type -80℃~+220℃
- Ambient temperature: -40℃~+120℃ (Remote display without LCD≤85℃)
- Fully welded stainless steel body. Durable casing
- Independent of medium’s physical and chemical states
- Suitable for corrosive, toxic and explosive medium environments
- Interface measurement or level measurement of 2 kinds of medium with different densities
- Easy-to-read displays on all flow meter types）
- Two-wire 4~20mADC signal output available
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Variable Area Flowmeter | 335
Price range: R3,590.00 through R12,097.00
Variable Area Flowmeter 335 Overview

The Variable Area Flowmeter 335 from GF Piping Systems are radially installed, dismountable meters for measuring the flow rate in industrial piping system constructions. The measuring principle is advanced and efficient. The measurement ranges, which are tailored to our customers‘ needs, and the range of materials available for the tubes and screwed fittings, allow the flow meters to be used for a wide range of applications and a great variety of media.

Function
If a medium flows upwards through the vertically mounted measuring tube at a sufficient flow velocity, the float is raised to the point at which a state of equilibrium sets in between the lifting force of the medium and the weight of the float. As the mean flow velocity is proportional to the quantity flowing through per unit of time, this state of equilibrium corresponds to the measurement of the current flow volume.

Variable Area Flowmeter 335 Features
- Easy and cost-effective measurement principle.
- No additional energy required for the operation.
- Easy reading of the measured value.
- Available scale range from 50 l/h up to 60 000 l/h.
- Printed double scale for water in percent and l/h.
- Special scales for liquid and gaseous media can be attached.
- Wide range of materials.
- Break-proof and corrosion-resistant.
- Large dimensions with guiding rod (PVDF-coated).
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Glass Tube Variable Area Flowmeters | DS3601-100mm

Glass Tube Variable Area Flowmeters - Overview

This Glass Tube Flowmeter uses a 100mm scale length borosilicate glass tube and a float. As it is based on the variable area (VA) principle, these flowmeters provide clear, simple and reliable operation. They are individually scaled and calibrated according to the customer's requirements. The fluid or gas flows vertically upwards through the tapered glass tube, causing the float to rise to an equilibrium position. The flow rate is measured by reading the top edge of the float against the scaled tube. Suitable for use with gasses or water (eg. cracked ammonia, helium, hydrogen, methane, nitrogen, oxygen, propane).

Glass Tube Variable Area Flowmeters - Features
- Instantaneous response
- Simple and reliable operation
- Low line pressure loss
- High resolution
- Custom scales available on request
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Variable Area Vertical Pointer Flowmeter | RWLZ

Variable Area Vertical Pointer Flowmeter - Overview

The LZ series is a no-contact and zero-hysteresis variable area flowmeter. It is a high-precision, high-reliability signal transmitter. It detects changes in the angle of the magnetic field of the magnetic sensor. This high-performance flowmeter is available with an indicator or with LCD display and includes power failure protection. The LCD can display the instantaneous flow, total flow, loop current, environment temperature, damping time, and small signal removal. Optional Two-wire 4~20mA signal (with HART communication) output available. It is not affected by the medium’s physical and chemical states such as conductivity, dielectric constants, etc. The Variable Area Vertical Pointer Flowmeter is ideal for small and medium flow measurements of single-phase liquids or gas with small and medium pipe diameters. Suitable for use with mediums that are corrosive, toxic and explosive. Applications include chemical, pharmaceutical, petrochemical, food, and metallurgical industries.

Variable Area Vertical Pointer Flowmeter - Features
- Medium temperature: Normalised type -80℃~+220℃
- Ambient temperature: -40℃~+120℃ (Remote display without LCD≤85℃)
- Range ratio: 10:1 (Special type 20:1)
- Accuracy class: 2.5 (Special type 1.5% or 1.0%)
- Working pressure: DN15~DN50 PN16 (Special type 2.5MPa)
- Durable - fully welded stainless steel body
- Suitable for most mediums
- Easy-to-read displays
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Platon Fire Sprinkler Flowmeters | DS1163

Platon Fire Sprinkler Flowmeters - Overview

This is a robust, compact direct reading flowmeter, approved for use on lines from 80-150mm. Suitable for use in automatic sprinkler installations, water spray or deluge systems. Approved for regular monitoring and testing of such systems by the Loss Prevention Certification Board (LPCB), under their “Rules for Automatic Sprinkler Installations”, in the UK and equivalent organisations in other countries. The flow meter is a combination of two simple measuring elements. In the main flow line, an orifice plate is inserted between two pipe flanges, producing a pressure drop related to the flow rate. Across the orifice plate, a shunt or bypass loop uses this pressure drop to create a small flow through a similar orifice restrictor and a Variable Area flowmeter. The flow in the bypass VA meter is proportional to the main line flow, and special scaling on the glass tube allows the main line flow to be measured directly.

Platon Fire Sprinkler Flowmeters - Features
- Approved and listed by LPCB
- Easy installation between pipe flanges
- Instantaneous reading
- Simple water flow measurement
- No electrical power needed
- Isolation valves for tube replacement and cleaning
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Platon Glass Tube VA Flow Meter | DS1115

Platon Glass Tube VA Flow Meter - Overview

This Variable Area flowmeter consists of a glass flow tube and float scaled to the flow units required. It also has a frame to provide the end block supports and to cover and protect the tube. The NGX series frames use flow tubes with 100mm long scales, whereas the smaller LGX frames use flow tubes with 30mm scales. To choose a complete flowmeter select the frame code required, and separately specify the fluid flow range needed on the flow tube scale. NGX and LGX series frames are designed to fit your process. The options available allow easy installation as they are surface mounted on a vertical panel. Process connections and labelling can be customised to suit the application. For accurate measurement.

Platon Glass Tube VA Flow Meter - Features
- Improved industrialised construction
- Easy to use
- High visibility scale
- Rear ‘blow out’ safety vent
- Ergonomic design
- Standard or custom scaled glass tubes to suit process fluids and conditions
- Range of process connections to fit pipe-work requirements
- Brass or Stainless Steel end blocks with optional integral flow control valve
- Supplied with studs for surface panel mounting
- UV stabilized rigid safety cover
- Gas or liquid flow measurement
- Operator confidence from float rotation
- Instantaneous response
- Accuracy up to ±1.25% FSD
- Air flow range 5 mL/min to 150 L/min
- Customized scales
- Glass tube removal without tools
- ATEX Infra-red alarm option
- Range of accessories
- UKAS calibration optional
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Platon Infra-Red Flow Alarm | DS1120

Platon Infra-Red Flow Alarm - Overview

The Platon Infra-Red Flow Alarm DS1120 uses an infra-red beam across the glass flow tube of a Variable Area (VA) flowmeter to determine float position. Passage of the float between the sensor arms is detected, and the sensor determines whether the float is above or below the sensor position. Electronics inside the sensor module give an open collector transistor output, suitable for external logic circuits. Suitable for all gas flows and liquid flows where the float is visible. The sensor is clipped to the back of the flowmeter frame. Movement up and down the frame allows the sensor to provide a flow alarm at any point on the tube scale, as required. The optional mains interface and relay module are used to provide the DC power needed to drive the sensor electronics, plus a SPCO 8 Amp mains relay output. This relay acts as a slave to the transistor output from the sensor module. Each relay module has two output relays and can be used to monitor two separate alarm sensors.

Platon Infra-Red Flow Alarm - Features
- High or low flow arm
- Intelligent: Knows whether float above or below sensor
- Adjustable over full range of flow tube
- Suitable for normal (NG/NGX) or miniature (LG/LGX) flowmeters
- DC output direct to standard logic circuits
- Optional mains interface relay module
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Platon Metal Tube GMT Flanged VA Flow Meter | DS1220

Platon Metal Tube GMT Flanged VA Flow Meter - Overview

These variable area meters are made of totally welded stainless steel. The robust construction has no glands or seals to leak which makes the meters suitable for high-pressure applications or extreme temperatures. Liquid flowing up the tapered flow tube lifts the float to an equilibrium position according to the flow rate. A magnetically coupled pointer indicates this flow on an external scale. The large meter indication is easily visible with the pointer moving over a 1500 scale. Each scale is produced specifically for the fluid involved and the process conditions expected. Several flow ranges are available for meters of each standard line size. Meters can be supplied with EN, ANSI or other standard flanges, or BSP or NPT screwed connections. The standard GMT is self-contained and needs no external power. Alternative materials are available for special orders eg. Hastelloy or Monel wetted parts. Brass or Stainless steel bodied meters are also available with screwed connections. The indicator can be provided with one or two flow alarm sensors which are adjustable over the meter operating range. Full electronic transmission and totalisation are available using the “VAMPIRE” electronic module. These flow meters have particular advantages over glass flow meters where fluids are opaque or staining, or where higher safety and security for dangerous or toxic fluids are required.

Platon Metal Tube GMT Flanged VA Flow Meter - Features
- Easy installation—flanged or screwed
- For high pressure or extreme temp applications
- ½” - 4” line sizes
- No power required
- Clearly visible meter
- Scaled for process fluids
- No glands or seals
- Robust, simple construction
- Pulsation damper on gas meter
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Platon Plastic Tube VA Meter | DS1132 GR/GRV

Platon Plastic Tube VA Meter - Overview

The Platon GR/GRV flowmeters are moulded plastic tube variable area meters with ball floats. The precision moulded tapered tube has guides to stabilise the float, allowing easy flow reading against the clear 50mm long scale. Units are available calibrated for air or water flows. Typical applications are for operator monitoring of cooling, purging or sample flows. The GRV option has a built-in multi-turn flow control valve for simple adjustment of flow rates. Designed for vertical mounting on a control panel, the flowmeter is supplied with brackets for flush mounting through a cut-out of approximately 116 x 19mm. Alternatively, the meter can be surface mounted. For an immediate indication of process alarm conditions, adjustable transparent indicators can be clipped into the flowmeter face, presenting a red limit line at the required flow rate. These accessories can be used to show the limits of normal flow adjustment or an alarm level. Reliable and rugged process connections are made to stainless steel 1/8 NPT female threads built into a stainless backplate within the meter. The polycarbonate body and flow tube are O-ring sealed to the backplate, and can simply be disassembled for any necessary cleaning or interchange of flow scales.

Platon Plastic Tube VA Meter - Features
- Low-cost flow indication
- Air or water calibration
- Easily readable 50mm scale
- Stainless steel rear connections
- Set point indicator flag
- Flow control valve option
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Horizontal Display Metal Tube Rotameter | QTLZ

Horizontal Display Metal Tube Rotameter - Overview

This Variable Area Rotameter is suitable for single-phase liquids or gas flowing in small/medium pipe diameters. It can be used with corrosive, toxic and explosive mediums. It has good stability and reliability. It has an easy-to-read LCD digital display screen and is easy to install. Applications include the Chemical, Pharmaceutical, Petrochemical, Food, and Metallurgical Industries.

Horizontal Display Metal Tube Rotameter - Features
- Horizontal Installation, easy installation and observation
- Good stability and reliability
- Suitable for single-phase liquid/gas with small/medium pipe diameter
- Can be used for corrosive, toxic and explosive mediums
- Two-wire 4~20mADC signal output
- Easy-to-read LCD digital display
- Range ratio: 10:1 (Special type 20:1)
- Accuracy class: 2.5 (Special type 1.5% or 1.0%)
- Medium temperature: Normalized type -80℃~+220℃
- Ambient temperature: -40℃~+120℃(Remote display without LCD≤85℃)
- Working pressure: DN15~DN50 PN16 (Special type 2.5MPa)
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Digital Vertical Metal Tube Rotameter | QTLZ Male Thread

Digital Vertical Metal Tube Rotameter - Overview

This Rotameter is a variable area flow measuring instrument. The 16-bit microprocessor and high-quality components in the instrument ensure excellent performance of the flowmeter in various kinds of applications. The 304/316 stainless steel structure can be used to measure the flow of liquid, gas, and steam. It is especially suitable for measurement of low flow rate, microflow range, high temperature, high pressure, corrosive, conductive or non-conductive mediums. Applications include petrochemicals, chemicals, food and bev, water treatment and other industries.

Digital Vertical Metal Tube Rotameter - Features
- Range ratio: 10:1(Special type 20:1)
- Accuracy class: 2.5(Special type 1.5% or 1.0%)
- Working pressure: DN15~DN50 PN16 (Special type 2.5MPa)
- Medium temperature: Normalized type -80℃~+220℃
- Ambient temperature: -40℃~+120℃(Remote display without LCD≤85℃)
- Double indication system
- Separation of magnetic coupling and magnetic signals
- Double-line liquid crystal digital display
- Bore diameter of the measuring tube of the flowmeter is complete
- Resistance to high temperature and high pressure
- Good protection and explosion-proofing performance
- Full series of installation pattern
- Various kinds of power supply patterns
- Highly integrated circuit
- Systematical software function and standard Hart communication pattern
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Platon Plastic VA Flowmeter | DS1140

Platon Plastic VA Flowmeter - Overview

Type PG and PGU flowmeters are low-cost variable area flowmeters for liquids or gases, in pipe sizes 1/2” or 1”.The shatterproof TPX moulded tapered indicator tube has a 100mm linear flow scale with a 10:1 flow range. The stainless steel or Dural float rises with the flow to an equilibrium position. The flow rate is then read from the top of the float. Scales are etched directly onto the plastic flow tube ensuring high float visibility so that it can be easily read at a distance. They are available with air or water scales etched into the flow tube. Glass tubes are also available, which can be supplied with custom scales to suit process conditions, in the PGU housing. TPX plastic has excellent resistance to most chemicals and gases. It is also non-toxic and boilable.

Type PG is a lightweight, open construction ideal for surface mounting or portable use. For alternative process liquids or conditions, external laminated scales are provided and positioned in front of the flow tube.

Type PGU has a rigid diecast housing with a Perspex window, giving it complete protection from random damage. This flowmeter is suitable for unsupported mounting in process pipework.

Platon Plastic VA Flowmeter - Features
- Large flow capacity for use on 1/2” and 1” lines
- High visibility
- Instantaneous in operation
- Suitable for use on a wide range of liquids and gases
- Glass tube or special scale options
- Low-pressure drop
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Shunt Orifice SGUV | Platon DS1160

Shunt Orifice SGUV - Overview

The type SGUV and type SGUL are direct reading Flowmeters for clean liquids and gases in pipe sizes larger than 30mm. They provide a robust and cost effective method of flow measurement. The indicator housing can be mounted locally to the pipe or remotely by the use of flexible impulse tubing. The instrument is a combination of two measuring principles. It is essentially a pressure differential device consisting primarily of an accurately machined orifice plate located in the main pipework. This produces a pressure drop proportional to the square of the flow rate. A secondary orifice restrictor located in the by-pass flowmeter is accurately calibrated to produce a by-pass flow that can be measured by the glass VA type flowmeter, scaled in terms of the main pipe flow. The metering elements are manufactured to a high standard of interchangeability with boldly marked indicating scales and dynamically balanced floats.

Shunt Orifice SGUV - Features
- Calibration for wide range of gases and liquids
- Available for various flanges
- Instantaneous reading
- Ease of installation
- Compact and rugged construction
- Optional flow alarm
- Maintenance possible under flow conditions
- Interchangeable components provide low cost unit
- Only one moving part
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High Pressure Liquid Flow Meter | DS1171

High Pressure Liquid Flow Meter - Overview

This metal-bodied flow meter functions using a spring-loaded orifice moving over a tapered cone, creating a variable area flow meter. The flow is indicated by a magnetic follower ring under a scale on an external glass tube. The flow reading is independent of viscosity up to 200 cs. Suitable for water or oil.

High Pressure Liquid Flow Meter - Features
- Works in any orientation
- Pressure up to 350 bar (5000 psi)
- Accuracy ±5% FSD
- Repeatability ±1% FSD
- Direct reading
- Relatively insensitive to viscosity changes
- Oil or water calibrated
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Metal Tube Flowmeters | SC250

Metal Tube Flowmeters - Overview

This variable area, high-performance measurement flowmeter, is suitable for use in extreme working conditions. Can be used in liquid or gas flow measurement. Applications include water treatment plants, pulp & paper and food industries; pharmaceutical, chemical and petrochemical industries; power plants and nuclear-generating plants; heating and cooling circuits; saturated steam circuits; oven treatments and control of gas burners.

Metal Tube Flowmeters - Features
- Metallic tube with a robust construction
- Indication using magnetic coupling
- High-performance measurement in extreme working conditions
- High resistance to corrosion
- Low-pressure drop
- Damping mechanism to avoid float bounces in gas and steam applications
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