Presentation on theme: "What are Flow meters A flow meter is an instrument used to measure linear, nonlinear, mass or volumetric flow rate of a liquid, steam or a gas. Selecting."— Presentation transcript:
What are Flow meters A flow meter is an instrument used to measure linear, nonlinear, mass or volumetric flow rate of a liquid, steam or a gas. Selecting a Flow meter The basis of good flow meter selection is a clear understanding of the requirements of the particular application. Evaluating the nature of the process fluid and of the overall installation. Innovative Technologies, Creative Solutions Quality & Simplicity in Flow Measurement
Key questions which need to be answered before selecting a flow meter: What is the fluid being measured by the flow meter. Do you require rate measurement and/or totalisation from the flow meter? What viscosity is the liquid? Characteristics of the fluid (Is the fluid clean, have particles?) Do you require a local display or do you need a signal output? What is the minimum and maximum flow rate ? What is the minimum and maximum pressure? What is the minimum and maximum temperature? Is the fluid chemically compatible with the flow meter ? If this is a process application, what is the size of the pipe?
How To Select a Flow meter Line Size – Do not choose meter on line size. Flow Range – Same size meters can have totally different flow ranges. Fluid Compatibility – Check meter materials of manufacture are compatible with fluid. Viscosity –F low de-rating factors or limits may apply. Connections –P ressure rating of meter flanges. Protection – Choose correct mesh size for strainers. Accuracy & Repeatability – Repeatability is the more important parameter
The turbine meter normally has an accuracy of 0.5% of the reading. It is a very accurate meter and can be used for clean liquids and viscous liquids up to 100 centistokes. A minimum of 10 pipe diameters of straight pipe on the inlet is required. The meters consists of a multi- bladed rotor mounted at right angles to the flow and suspended in the fluid stream on a free-running bearing.
One of the most popular cost effective flowmeters for water or water like fluids. Many are offered with flow fittings or insertions styles. These meters like the turbine meter require a minimum of 10 pipe diameters of straight pipe on the inlet and 5 on the outlet. The rotor of the paddlewheel sensor is perpendicular to the flow and contact only a limited cross section of the flow.
Positive Displacement meters come in various configurations & are a very versatile flow meter, best suited for high viscosity & non–conductive liquids. They have high accuracy (linearity & repeatability) with low flow and precise batch capability. Meter requires no flow conditioning for simple installation and are easy to understand & service. Oval Gear Rotary Piston
Positive Displacement Oval Gear Flow Meters
Among the many Positive Displacement flow meter design principals available today, the oval gear wheel still holds a top place in simplicity & field proven performance. GEAR WHEEL FLOWMETER
OPERATION OF OVAL GEAR FLOW METER
Trimec Flow Products Oval Gear Wheel meters provide high levels of accuracy & repeatability for a wide range of clean liquids irrespective of viscosity & conductivity either pumped or gravity fed.
Flow range: 0.5 litres / Hr ~ 2500 litres / min. Nominal sizes: 4mm ~ 100mm pipe size Linearity: +/- 0.5% of reading ( +/- 0.2% with linearisation ) ( +/- 1% for Mechanical Displays ) Repeatability: +/- 0.03% Temperature: -20 ~ +120 Deg C - Standard Materials: aluminium or 316 stainless steel Pulse outputs: reed & NPN open collector Mechanical Displays: 3,4 & 5 digit General Specifications Oval Gear Flow Meters
Optional Rotor Material - on all meter sizes ( excludes extended flow versions ) Rotor Stability ( On Metal Rotors ) ( On Metal Rotors ) 120 Deg. Temp. Rating. ( High temp rotors not required ) Aluminium, Ryton & Stainless Steel materials. Metal Roller, Carbon or Ceramic Bearings Metal Roller, Carbon or Ceramic Bearings. BENEFITS Meter Features
Modular Process Connections Available on 25mm to 100mm meter sizes. Simplifies Installation Screwed or Flanged connections. Stainless option on screwed versions. Meter Features
Dual Outputs ( reed & Hall ) Standard. Quadrature Pulse Output Option. Pulse Interrogation connection High Pulse Output option ( Hall only ) Pulse Output Boards Meter Features
Low & High Flow Capabilities Broad Range 1/8” to 4” 0.5 LPH to 2500 LPM High Precision +/- 0.5% Optional +/- 0.2% with linearization Unaffected by pulsations No Flow Conditioning required Meter Features
Available as pulse meter only or with integral or remote mount LCD or mechanical registers. Dual Outputs ( reed & hall) as standard. Weatherproof IP66 / 67 LCD models Flameproof / Explosion proof construction Atex & IECeX Intrinsically Safe Integral Instruments. Modular connections for adaptability and ease of installation and service. Quadrature pulse output option for pulse verification or forward / reverse measurement. High Flow Capabilities ( 2500 lpm ) NMI Certification ( Resale Purposes ) meter sizes 1” to 4” fitted with air eliminator strainer and approved register. Meter Features
High Precision / High resolution ( Pulses per Litre ) 120 Degree Temperature Rating as standard. High & Low viscosity applications. 3, 4 or 5 digit Mechanical Registers with large number displays. ( Metal Housings with or without accuracy adjustment ) Gearbox fitted with stainless steel gears as standard. Aluminium rotors fitted with high speed roller bearings. Stainless rotors fitted with ceramic or carbon bearings. Ryton Rotors Viton seals as standard. Meter Features
Advantages Opposition Metal & Plastic Rotors Metal & Plastic Modular Connections Cast in meter body Higher Temperatures -120deg 80 deg. Higher Flows 25mm size – 150 lpm 120 lpm Larger Flow Range – 2500 lpm 1200 lpm More Models – Extended Capacity N/A Ductile Iron material N/A ATEX & IECex approvals N/A NMI approval Mechanical Meters N/A Accuracy Adjustment – Mechanical N/A Viton seal standard Nitrile Electronics – own manufacture Fluidwell / Flux Gearbox – stainless gears Plastic Gears Large size reset number display Small reset numbers Meter Features
Low Pressure Drop standard feature. Extended Flow Models available in 2”, 3” & 4” sizes. Factory calibration & accuracy certificate supplied. Flexibility of Installation. ( vertical or horizontal lines ) Min. number of moving parts in LCD pulse meters ( 2 Rotors ) Continued product development commitment. Standard Meter – Pulse Output Options ~ LCD Register ~ Mechanical Register ~ Batching Register Meter Specifications:
2 Rotors Reed Switch Meter Specifications: Minimum number of moving parts in pulse meters
Meter Selection Meter max. flow rates are based on 1 bar pressure drop With Fluids above 1200 cps. Meter sizing and required flow rate become important decisions. To achieve the lowest possible pressure drop, a range of special cut “ Keishi” high viscosity optional rotors are available. The Dimak series oval gear meters are extremely suited to measuring highly viscous materials with the pressure drop being the only limiting factor. Special rotors applies to meters sizes TF-008 to TF-100 also refer to de-rating factor for reduced flow rates applicable
Flowmeters Depending on the fluid viscosity the flow meters maximum flow rate may be de-rated according to the attached chart. Example:- TF25 meter measuring 6000 Cp Max Flow 150 lpm x 0.5 = 75 lpm new maximum flow rate to maintain 1 bar pressure drop. VISCOSITY CORRECTION
Special Cut Rotors: Above 1200 cps. Every 3 rd Tooth Removed Oval Gear Rotor VISCOSITY
Accuracy & Pressure Drop Curves
FBT11 Battery Powered Totaliser REMOTE OR INTEGRAL METER MOUNT Simultaneously displays re-settable (batch) total in engineering units as programmed by the user. When externally dc powered the instrument will produce an un-scaled or scaleable solid state output pulse which is NPN / PNP selectable.
FRT12 Flow Rate Totaliser REMOTE or INTEGRAL METER MOUNTING Simultaneously displays re-settable (batch) total & cumulative total in engineering units. When externally dc powered the instrument will produce an un-scaled or scaleable solid state output pulse which is NPN / PNP selectable.
FRT-40 Flow Rate Totaliser REMOTE or INTEGRAL METER MOUNTING Battery or External powered, 6 digit large LCD total & 8 digit cumulative totaliser, with 5 digit rate display. IP66/67 ~ Nema 4X aluminium housing. LCD Backlighting as standard. Scaled Pulse Output. Optional facia protection shield Metal Housing as standard
FEB10 Batch Controller REMOTE or INTEGRAL METER MOUNTING Provides automatic batch control with one or two stage outputs. Display provides batch quantity as well as status at each stage of the batch process. Batch limiting & no flow detection plus automatic over run compensation. Other features include remote stop / start, system interlocks and multiple batch controller networking.
When fitted to flow meter, the cooling fin allows meters to be fitted with electronic display to be rated to 120 deg C Compact design allows adequate heat dissipation in ambient temperatures Cooling Fin
FI-420 Frequency Converter The Frequency converter is a programmable, non volatile PCB which is link selected to serve as either a frequency to current converter (F/I) or a single point flow rate alarm device for high or low rate detection - Board fits onto flow meter output PCB. FI-420 Programmed at factory or in situ with hand held programmer
RELAY OUTPUT BOARD The relay output boards are an option for the Z3 & B1 Instruments. The relays will switch higher loads ( 5 Amp ) than the solid state switches provided as standard in these instruments
PD2 Pulse Discriminator Module Application is for discriminating bi-directional flows. Accepts two independent inputs from flow meters with quad pulse outputs. Discriminates flow direction from inputs and provides forward & reverse pulse outputs for each flow direction
PR2 Pulse Repeater Module The pulse repeater provides electronic protection to the flow meter output in situations where associated external circuitry may have heavy electronic loadings, non regulated power supplies or electrical surges or spikes
Exd Explosion Proof Housing Robust aluminium or stainless field mount housing. Four Large external non- invasive operational switches. IP66 ~ Nema 4X Rated. View, program & operate instruments without cover removal. Certifications – FM, ATEX, SAA Flow Instrumentation Products
Mechanical Registers Standard - without accuracy adjustment As an alternative to electronic totalisers, robust mechanical registers with metal housings offer 3 or 4 large resettable digits & 6 or 8 accumulative total displays clearly visible for loading & un-loading sites at petroleum depots, mining, construction & marine facilities M1 Register M3 Register Flow Instrumentation Products
Mechanical Registers V Style - with accuracy adjustment As an alternative to electronic totalisers, robust mechanical registers with metal housings offer 5 large re settable digits & 8 digit accumulative total displays clearly visible for loading & un- loading sites at petroleum depots, mining, construction & marine facilities V1 Register with accuracy adjuster Flow Instrumentation Products
Ticket Printers Meter Register and Ticket Printer combine together to produce clean, detailed printed records of high speed fluid deliveries and transactions Flow Instrumentation Products
Mechanical Preset Batch Registers As an alternative to electronic batch controllers or in Ex Proof applications, mechanical preset registers with shutoff valve are available in sizes from 2” to 4” Flow Instrumentation Products
STRAINERS As the meters are only suitable for clean liquids it is important that any impurities are removed prior to the meter. Typical Y Strainer SIZE Mesh Size MicronSize 1/4"200 mesh75DN8 3/8"200 mesh75DN10 1/2"100 mesh150DN15 1"50 mesh250DN25 1 1/2"50 mesh250DN40 2"25 mesh500DN50 3" 25 mesh500DN80 4" 25 mesh500DN100 Recommended Mesh Sizes
High Pressure Models Sizes up to 50mm Pressures to 400 Bar (6000 PSI ) Special end connections available Hall effect output Deep Sea applications Chemical Injection Hydraulic applications
Every Flowmeter undergoes a check before leaving the factory for correct operation & function of pulse outputs & ancillary electronics if fitted. Meters are then compared against a master meter which is traceable to the Australian National Standards & issued with a calibration report.
Company has 4 meter calibration test benches using certified master meters for validating meter accuracy. Small meters to 750 l/hr. Medium meters to 500 l/min. Large meters to 1500 l/min.
Installation Points: PD Meters do not work well with silty or dirty fluids ( Use Strainers before meter ) Straight Pipe not necessary before meter. Teflon Tape can cause rotor stoppages. High Velocity flows can cause rotor destruction ( Slowly ramp up flow on start up ) Avoid Water Hammer caused by closing valves quickly in batch applications Flush Pipe Lines prior to meter installation
strainer Flow meter isolation valve by-pass valve Open downstream valve last It is important when starting up the process that the downstream valve is slowly opened last RECOMMENDED INSTALLATION
Specialised Fuel Meters Low cost fuel flow meters designed for monitoring of fuel in Trucks, Buses & vehicles EM008 Meter EM025 Meter Additional Products