Training - Flow

Level 1 - Fundamental Training Flow

Power Point Presentation Handouts

Level 1 - Flow

1Level 1Fundamental TrainingFundamental Training

Level 1 - Flow

2

Topics: Slide No:• Why measure flow? 3 - 4• Flow terminology 5 - 18• Flowmeter selection 19 - 24• DP flowmeters 25 - 46• Velocity flowmeters 47 - 55• Mass flowmeters 56 - 61• Displacement meters 62• Flow products summary 63• Exercise 64 - 65

ContentsContents



Level 1 - Flow

3

Safety• Uncontrolled flow rates may cause

– temperature & pressure to reach dangerously high levels– turbines & other machinery to overspeed– tanks to spill

Custody Transfer• the measurement of fluid passing from a supplier to a

customer– cash register of the system– example a local gas station measures how much gas being

pumped into the vehicle for billing– requires high measurement accuracy

Product Integrity• ensuring right amount of blended materials in for example

processed food & gasoline

Why measure flow?Why measure flow?5 Common Reasons5 Common Reasons

Level 1 - Flow

4

Efficiency Indication• to determine efficiency of process by

– measuring the amount of each input that has gone into the product

– comparing the above measurement to the amount of product producedl

Process Variable Control• Flow rate is measured & controlled during energy transfer

application, for example– heat exchanger

» fluid temperature controlled by varying the flow rate of steam

Why measure flow?Why measure flow?5 Common Reasons5 Common Reasons



Level 1 - Flow

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Flow terminologyFlow terminologyFlow Control LoopFlow Control Loop

I/P FIC

TTFT

• Flow Loop Issues:– May be a Very Fast Process

» “Noise” in Measurement Signal⇒ May Require Filtering

» May Require Fast-Responding Equipment

– Typically Requires Temperature Compensation

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• Density: ρ (rho) = m/V = mass/volume– Mass per unit volume at given operating conditions.– Common units: kg/m3 or lb/ft3– Density of a liquid varies with temperature– Density of a gas varies with temperature and pressure

Flow terminologyFlow terminologyFluid PropertiesFluid Properties

Liquids Gases↑ Temperature = ↓ Density ↑ Temperature = ↓ Density↓ Temperature = ↑ Density ↓ Temperature = ↑ Density

↑ Pressure = No change ↑ Pressure = ↑ Density↓ Pressure = No change ↓ Pressure = ↓ Density



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For Liquids,

• Specific Gravity =

For Gases,

• Specific Gravity =

Density of liquid at process temperature

Density of water at 15.6°C

Molecular Weight of gas

Molecular Weight of air


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• Gas Compressibility Factor: ZZ--factorfactor– Used to correct gas equations for real-gas effects.

Accounts for the deviation from the “ideal” situation.

» For an ideal gas Z=1 and PV=nRT(Ideal Gas Law).» The True Gas Law: PV=ZnRT» Z & n Can be found in engineering tables.» R is dependant on units chosen for P, T & V

PV = nRT

Absolute pressure

Volume

Molecular weight

Universal gas constant

Absolute temperature




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• Viscosity– Measure of a fluid’s tendency to resist a shearing

force, or to resist flow

» A greater force is required to shear high viscosity fluids than low viscosity fluids (viscosity = shear stress/shear rate).

» Viscosity normally decreases with an increase in temperature for a liquid, but increases with an increase in temperature for a gas

Force

FluidThickness

Fixed Plate

Area

•Water is 1cP, peanut butter is 10,000 cP


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• Fluid Type– Clean Fluid

» A fluid that is free from solid particles, e.g. clean water. – Dirty Fluid

» A fluid containing solid particles, e.g. muddy water.– Slurry

» A liquid with a suspension of fine solids, e.g. pulp and paper, or oatmeal.

– Steam» Water vapour

– Gas» Natural gas




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Laminar Flow Turbulent FlowTransition Flow


• Flow Profile

Higher velocity in the middle

Lower velocity at the edge

Lower velocity at the edge

Pipe Wall

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0 2000 4000

TransitionLaminar Turbulent

ReynoldsNumber

(Pipe I.D.) ( Velocity) (Density)Viscosity

Rd = (ρ x v x D)/μ

m m/s kg/m3

kg/ms


• Reynolds number defines the state of fluid flow– Dimensionless number– Indicates flow profile



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Flow conditions; Velocity = 0.5 m/sdensity = 995.7kg/m³Temperature = 25°CViscosity = 0.7cPPipe ID = 60mm(1 Poise = 0.1 kg/m s)

i) Find the Reynolds number for the fluid.ii) Identify the type of flow.

(a) Laminar(b) Transitional(c) Turbulent

= 42,673

RD = V.d.ϕ / μ

= 0.5 x 0.06 x 995.7 x 1000 /0.7

μ = 0.7 / 1000 kg/ms


Example:

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• Pressure & Temperature changes inside process pipedetermines which state the steam is in– Saturated steam (all vapor)

» Steam exactly at its saturation point (SP)⇒temperature & pressure at which liquid turns to vapor (as

pressure increases, saturation temperature increases)

– Superheated steam» Steam when pressure drop below SP» Steam when temperature rise above SP

⇒e.g. at 350 psia, saturation temperature for water is 222°C.⇒Steam at 350 psia & 278°C includes 56°C of super heat

– Quality steam ( mixture of water liquid & vapor)» Condensed steam when pressure rise above SP» Condensed steam when temperature drop below SP




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• Texture of inner walls– smooth wall ⇒ slightly increase fluid velocity– rough wall ⇒ slightly decrease fluid velocity

• Inside diameter– e.g., doubling the diameter increase flow rate by

as much as 4 times» Vol. flow rate(Qv) = Cross-section area * Velocity

= πD2/4 * Velocity= D2(π/4 x Velocity)

Flow terminologyFlow terminologyPipe Geometry & ConditionsPipe Geometry & Conditions

Qv = (22D)2 * (π/4 x Velocity)Qv = 44 (D2 * (π/4 x Velocity))

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• Flow Profile Disturbance– factors that cause flow profile to become irregular

» symmetrical profile⇒caused by reducers or expanders pipe sections⇒eliminated by inserting appropriate length of straight

pipes» asymmetrical profile

⇒caused by elbows, valves and tees⇒eliminated by inserting appropriate length of straight

pipes » swirl

⇒caused by pumps, compressors, or two pipe elbows in different planes

⇒eliminated by inserting flow conditioners

Flow terminologyFlow terminologyPipe Geometry & ConditionsPipe Geometry & Conditions



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• Metric Unit- m3/s• Others

⇒ StdCuft/s - Standard Cubic feet per second⇒ StdCuft/min - Standard Cubic feet per minute⇒ StdCuft/h - Standard Cubic feet per hour⇒ StdCuft/d - Standard Cubic feet per day⇒ StdCum/h - Standard Cubic meter per hour⇒ StdCum/d - Standard Cubic meter per day⇒ NmlCum/h - Normal Cubic meter per hour⇒ NmlCum/d - Normal Cubic meter per day

Volumetric Flow Rate

Std - reference to 14.696 psi Atm. at 68 deg.FNml - reference to 101.325 Atm. At 0 deg.C

Flow terminologyFlow terminologyEngineering UnitsEngineering Units

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Mass Flow Rate• Metric Unit- kg/s• Others

⇒ lbs/sec - Pounds per second⇒ lbs/min - Pounds per minute⇒ lbs/hour - Pounds per hour⇒ lbs/day - Pounds per day⇒ gram/sec - grams per second⇒ grams/min - grams per minute⇒ grams/hour - grams per hour⇒ kg/min - kilograms per minute⇒ kg/hour - kilogram per hour

Flow terminologyFlow terminologyEngineering UnitsEngineering Units



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FlowmeterFlowmeter selectionselectionSpecificationSpecification

• Accuracy– % of rate

» uncertainty of flow proportional to flow rate

– % of full scale» uncertainty of flow remains constant

Rate of Flow % of Rate Accuracy Uncertainty Range100 gpm ±2% of 100 gpm 98-102 gpm50 gpm ±2% of 50 gpm 49-51 gpm20 gpm ±2% of 20 gpm 19.6-20.4 gpm

Rate of Flow % of Rate Accuracy Uncertainty Range100 gpm ±2% of 100 gpm 98-102 gpm50 gpm ±2% of 50 gpm 49-51 gpm20 gpm ±2% of 20 gpm 19.6-20.4 gpm

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FlowmeterFlowmeter selectionselectionSpecificationSpecification

• Rangeability (Turndown)– Meter maximum

» maximum flow rate that a flowmeter is capable of reading

⇒commonly used for magnetic, vortex and Coriolismeters

– Application maximum» maximum flowrate that occurs in the process flow

of a particular application⇒commonly used for orifice plates, flow nozzles, and

venturi tubes• Repeatability

– the ability of a flowmeter to produce the same measurement each time it measures a flow



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Flow Technologies

Mass Volumetric Head

VelocityMeter

PositiveDisplacement

Meter

Coriolis MeterThermal Meter

DP FlowMeter

TargetMeter

AnnubarOrificeVenturiNozzle

Elbow Taps

MagneticVortex

UltrasonicTurbine

Oval Nutating disc

GearGerotor

FlowmeterFlowmeter selectionselectionClasses of Classes of FlowmetersFlowmeters

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.• Displacement Meters– measure volume flow rate Qv directly by

repeatedly trapping a sample of the fluid. » total volume = sample volume * number of samples

⇒High pressure loss• Head Meters (DP Flow Meters)

– measures fluid flow indirectly by creating & measuring a differential pressure by means of a restriction to the fluid flow




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A reliable flow measurement is dependent upon the correct measurement of A and v.

• Velocity Meters– FLOW is measured inferentially by measuring

VELOCITY through a known AREA.» With this indirect method, the flow measured is the

volume flow rate, Qv. Stated in its simplest term» QV = A * v where

⇒A: cross-sectional area of the pipe⇒v: fluid velocity

» m3/s = m2 * m/s


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• Mass Meters– Infer the mass flow rate via the equation;

» Qm = Qv * ρ where,⇒Qm: the mass flow rate⇒Qv : the volume flow rate⇒ρ : fluid density

» kg/s = m3/s * kg.m3

– Consist of 2 devices;» One device will measure fluid velocity» The other device will measure fluid density




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Flow Restriction in Line cause a differential Pressure

Line Pressure

Orifice Plate(Primary Element)

QV= K DP

Constant

DP DP flowmeterflowmeterDP Flow EquationDP Flow Equation

H.P. L.P.

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FE

FTFIC

Outputs represent true flow only under specified conditions. Using “constants” in flow equations assumes a static flow

environment.For DP flowmeter output to represent true flowtrue flow, the following fluid properties must be constant:

Fluid density Fluid viscosity,

DP volumetric flow

QV= K DPPrimary Element

Pressure Transmitter

Flow Controller

Control Valve




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• For varying fluid densityfluid density and viscosityviscosity– Compensation is required to represent TRUE flow

QM= K DP*(P/T) Partial Compensation

Takes care of Density only

Mass Flow, QM = Volumetric flow * Density= m3/s * kg/m3

= kg/s


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Traditionally way of partially compensated DP mass DP mass flowflow has been accomplished using a “system.”

FE

TTFT

PT FC FICPressure

Transmitter(AP)

Pressure Transmitter

(DP)

Temperature Transmitter + Sensor

Flow Computer

Flow Controller

Control Valve

Primary Element

QM= K DP*(P/T)




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C dActual_flow

Theoretical_flow

• Cd is a correction factor to the theoretical equation.

Equations for calculating Cd are derived from experimental data.Cd is a function of beta ratio and Reynolds number, and is differentfor each primary element.

Discharge Coefficient (Cd)

• Density is NOT constant for gases. Y 1 1Y 1 f ,,,β k ΔP P 1 for Liquids:

k is the isentropic exponent, a property of gases:

kC pC v

Gas Expansion Factor (Y1)

= < 1

(Beta ratio = restriction diam. / pipe diam.)


QM= K DP*(P/T)

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Cd

RD102 103 104 105

Concentric Square-edge Orifice

GASESLIQUIDS

Discharge Coefficient vs. RD

CONSTANT




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0 5 104 1 105 1.5 105 2 105 2.5 105 3 105 3.5 105 4 105 4.5 105 5 1050.59

0.6

0.61

0.62

0.63

0.64

0.65

0.66

Beta = .75Beta = .6Beta = .5Beta = .4Beta = .2

Orifice Plate Discharge Coefficients

Pipe Reynolds Number

Dis

char

ge C

oeffi

cien

t

( 4” Flange Taps )

Discharge Coefficient vs. RD & β

Orifice Diam. / Pipe Diam. = Beta⌫ d/D = β

Beta Values are almost constant


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0 20 40 60 80 100 120 140 160 180 200 220 240 2600.85

0.9

0.95

1

1000 psi250 psi100 psi50 psi20 psi

Gas Expansion Factors

Differential Pressure (inH2O)

Gas

Exp

ansi

on F

acto

r

( k=1.3, beta = 0.6 )

Gas Expansion Factor vs. DP

LinePressure

The higher the line pressure, the more constant Gas Expansion Factor for a variety of DP




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Secondary - measures the differential pressure.

SECONDARY

Using well-established conversion coefficients which depends on the type of head meter used and the diameter of the pipe, a measurement of the differential pressure may be translated into a volume rate.

DP Flow Meters consist of two main components:

PRIMARY

Primary - placed in the pipe to restrict the flow. Orifice, Venturi, nozzle, Pitot-static tube, elbow, and wedge.

DP DP flowmeterflowmeterComponentsComponents

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• Simplest and least expensive.• Constrict fluid flow to produce diff. pressure across the plate.• Produce high pressure upstream and low pressure downstream.• Flow proportional to square of the flow velocity.• Greater overall pressure loss compared to other primary

devices.• Cost does not increase significantly with pipe size (advantage).

DP DP flowmeterflowmeterOrifice PlateOrifice Plate



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• Gradually narrows the diameter of pipe.• Resultant drop in pressure is measured.• Pressure recovers at the expanding section of the meter.• For low pressure drop and high accuracy reading applications• Widely used in large diameter pipes.

DP DP flowmeterflowmeterVenturiVenturi TubeTube

High Pressure Side Low Pressure Side

Cross sectionArea A2

CrosssectionArea A1 Flow

P1 P2

Q (Actual) = C x A1 x A2 2 x ( P1 -P2 )

( A12 - A2

2 ) ρx

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• High velocity flow meter.• Elliptical restriction of flow at nozzle opening.• No outlet area for pressure recovery.• For application where turbulence is high (Re > 50000)

eg.,stream flow at high temperatures.• Pressure drop falls betw. That of venturi tube and orifice plate

(30-95%)

DP DP flowmeterflowmeterFlow NozzleFlow Nozzle

D

D

d

D/2

FLOW

NOZZLE

High Pressure Low Pressure



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P Vg

Pf

f

f

c

f

f

1 12

2

2ρ ρ+ =

P Pf f1 2

Vf

f

1

ρ

Bernoulli’s energy balance for anincompressible, non-viscous fluid:

In order to measure accurate flow rate, a pitot traverse is required.

• Stagnation Pressure Sensing - measures a point velocity.

( )V

g P Pf 1

c f f

f

2 12

=−

ρTheoretical Point Velocity

DP DP flowmeterflowmeterPitotPitot TubeTube

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Fluid Flow

Low (Static) Pressure TapHigh (Impact) Pressure Tap

Static pressure portHigh pressure port

DP DP flowmeterflowmeterPitotPitot TubeTube

• One-point velocity measurement– accuracy affected by changes in velocity profile– tube must be moved back & forth in the flow

stream for average measurement



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High Pressure Tap Low Pressure Tap

Cross section of Annubar

Blunt Front

Sharp Edge

Blunt Rear

H.P. L.P.

Fluid Flow

DP DP flowmeterflowmeterAveraging Averaging PitotPitot Tube (Tube (AnnubarAnnubar))

• Include several measurement ports over the entire diameter of the pipeline– more accurate flow measurement than the regular

pitot tube

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• Advantages:– Can be inserted through a small opening.– Can sample the velocity at many points.– Low pressure drop, non-obstrusive.

• Disadvantages:– Pitot traverse requires a technician, and is time-

consuming.– Pitot tube is fragile (not suited for industrial app.)– DP signal is low.– Accuracy depends on the velocity profile.– Easily plugged by foreign material in the fluid.

DP DP FlowmeterFlowmeterPitotPitot TubeTube



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DP DP flowmeterflowmeterWedge Flow ElementWedge Flow Element

• inserted in the process pipe• forms a wedged obstruction on the inner wall of

the pipe• usually used with remote seals for measuring

– dirty fluids, slurries & fluids at high viscosity (low RD) that tends to build up or clog orifice plates

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DP DP flowmeterflowmeterVV--Cone Cone

• high accuracy• normally lab-calibrated• work equally well with short and long straight pipes• for customers who have limited room for straight

piping requirements• can be used with some dirty fluids



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Head MeterHead MeterRotameterRotameter

• Variable-area flowmeters– float inside the tapered tube rises in response to fluid flow rate– pressure is higher at the bottom than the top of the tapered tube– float rests where the dp between upper & lower surfaces of the

float balances the weight of the float– flowrate read direct from scale or electronically

• commonly used for indication only

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Head MeterHead MeterTarget MeterTarget Meter

• A disc is centered in the pipe with surface positioned at right angle to the fluid flow.

• Force of the fluid acting against the target directly measures the fluid flow rate.

• Requires no external connections, seals or purge systems.

• Useful for dirty or corrosive fluids.



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Advantages:• Low cost• Easily installed and/or

replaced• No moving parts• Suitable for most gases

or liquids• Available in a wide

range of sizes and models

Disadvantages:• Square-root head/flow

relationship• High permanent

pressure loss• Low accuracy• Flow rage normal 4:1• Accuracy affected by

wear and/or damage of the flow primary element especially with corrosive fluids.

Head MeterHead MeterTarget MeterTarget Meter

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As the conductive process liquid moves through the field with average velocity V, the electrodes sense the induced voltage.

• Faraday’s Law of electromagnetic induction.

• A voltage will be induced in a conductor moving through a magnetic field.

• E = kBDV– E = magnitude of induced voltage– V = velocity of the conductor– D = width of the conductor– B = strength of the magnetic field– k = proportionality constant

Velocity MeterVelocity MeterMagnetic Magnetic FlowmeterFlowmeter

ConductiveProcess Medium

Lining

Field Coils

Sensing Electrodes

SST Tube

Flange

Magnetic Field “B”(Constant Strength)

“E”

“E”

Variable Flow Rate(Feet Per Second)

“D”D

“V”



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Advantages:• Obstructionless flow• Unaffected by viscosity,

pressure, temperature and density

• Good accuracy• No RD constraints• Suitable for slurries and

corrosive, nonlubricating, or abrasive liquids

• Wide rangeability (30:1)

Disadvantages:• Liquid must be

electrically conductive• Not suitable for gases• Can be expensive,

particularly in small sizes

• Must be installed so that the meter is always full

Velocity MeterVelocity MeterMagnetic Magnetic FlowmeterFlowmeter

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An alternating voltage is produced as each blades cuts the magnetic lines of flux. Each pulse represents a discrete volume of liquid.

• Consist of multi-blade rotors supported by bearings and enclosed in a pipe section. perpendicular to fluid flow.

• Fluid flow drives the rotor.• Rotor velocity is proportional to

overall volume flow rate.• Magnetic lines of flux created by a

magnetic coil outside the meter.

Velocity MeterVelocity MeterTurbine MeterTurbine Meter

FLOWRotor Blades

Pickup Probe



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Advantages:• High accuracy• Rangeability 10:1• Very good repeatability• Low pressure drops• Can be used on high

viscosity fluids (but with lower turndowns)

Disadvantages:• Moving parts subject to wear• Can be damaged by

overspeeding• High temperature,

overspeeding, corrosion, abrasion and pressure transient can shorten bearing life

• Rather expensive• Filtration required in dirty fluids

Velocity MeterVelocity MeterTurbine MeterTurbine Meter

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Velocity MeterVelocity MeterVortex Vortex FlowmeterFlowmeter

Shedder Bar

Vortices

FLOW

Force on Sensor

Sensor

PivotingAxis

ShedderBar

Vortex Shedder Force

FLOW

• von karman effect (vortex shedding)– As fluid pass a bluff body, it

separates and generates small eddies/vortices that are shed alternately along and behind each side of the bluff body.

– This vortices cause areas of fluctuating pressure that are detected by a sensor.

– The frequency of vortex generation is directly proportional to fluid velocity.



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Advantages:• Good accuracy• Usually wide flow range• Used with liquids, gases

and steam• Minimal maintenance (no

moving parts)• Good linearity over the

working range

Disadvantages:• Not suitable for abrasive or

dirty fluids• Straight upstream pipe

required equal to 30 times pipe diameter or longer

• Limited by low velocity (RD < 10,000)

Velocity MeterVelocity MeterVortex Vortex FlowmeterFlowmeter

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Velocity MeterVelocity MeterUltrasonic Ultrasonic FlowmetersFlowmeters

• uses sound waves to determine flow rates of fluids.– Transit-Time Method

» 2 piezoelectric transducers mounted opposing, to focus sound waves between them at 45° angle to the direction of flow within a pipe. In a simultaneous measurement in the opposite direction to fluid flow, a value (determined electronically) is linearly proportional to the flow rate.

Receiver

Transmitter

FLOW

Upstream Transducer

Downstream Transducer



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• uses sound waves to determine flow rates of fluids.– Doppler Effect Method

» One of the 2 transducer mounted in the same case on one side of the pipe transmits sound waves (constant frequency) into the fluid. Solids or bubbles within the fluid reflect the sound back to the receiver element. Frequency difference is directly proportional to the flow velocity in the pipe.

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Advantages:• Non-intrusive,

obstructionless• Wide rangeability (10:1)• Easy to install (especially

for clamp-on version)• Cost virtually

independent of pipe size• The flow measurement is

bi-directional

Disadvantages:• Maximum temperature 150°C• Particular fluid conditions are

required (TOF-type: clean liquids; Doppler-type: particles or impurities in the stream)

• Not very high accuracy (about ±2%)

• Doppler flowmeter clamp-on type requires a pipe of homogeneous material (cement or fibreglass linings must be avoided)




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• Operating Principle– Uses a obsructionless U-shaped tube as a sensor– Applies Newton’s 2nd Law of Motion to determine flow rate.– Force = mass x acceleration– The flow tube vibrates at its natural frequency by an

electromagnetic drive system.

Mass MeterMass MeterCoriolisCoriolis MeterMeter

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• Coriolis Effect– Fluid flowing through the upward moving tube, pushes

downward against the tube.– Fluid flowing out through the downward moving tube,

pushes upward against the tube.– The combination of upward and downward resistive forces

causes the sensor tube to twist (coriolis effect).




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• Signal Transmission– The amount the tube twist is proportional to the mass flow

rate of the fluid flowing through it.– Electromagnetic sensors located at each side of the tube

measures the respective velocity of the vibrating tube at these points.

– The sensor sends this information to the transmitter which gives an output signal directly proportional to mass flow rate.

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Advantages:• High accuracy: ±0.25%• Relatively low pressure

drops• Suitable for liquid and

gas flow• Easy to install• Flow range (10:1)

Disadvantages:• Expensive• Mounting is critical (no

vibration)• Heat-tracing is required

in some applications




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• Works on the principle of heat transfer by the fluid flow– Made up o 3 elements arranged along the direction of motion.

» high accurate temperature sensor at upstream» an electrical heater in between» high accurate temperature sensor at downstream

– The difference between the two temperature readings is proportional to the mass flow rate. (if the thermal properties of the fluid being metered are constant and known).

Mass MeterMass MeterThermal MeterThermal Meter

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Advantages:• No moving parts• Suitable for large size

pipe (insertion type)• Good rangeability (50:1)• Accuracy: ±1% FS• Low permanent pressure

losses

Disadvantages:• Meter sensitive to fluid heat

conductivity, viscosity, and specific heat

• Mostly gas service (only rare liquid service)

• Specific heat of the fluid must be known and constant i.e. the gas must have a constant composition

• Proper operation requires no heat losses due to conductive exchanges though the pipe walls

Mass MeterMass MeterThermal MeterThermal Meter



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• An example of positive displacement meter– Two meshing oval gears rotate as fluid flows through them– Gears trap a known quantity of fluid as they rotate– Each complete revolution of both the gears = 4 * amount of

fluid that fills the space between the gear and the meter body

– volumetric flow rate is directly proportional to the rotational velocity of the gears

Displacement Displacement flowmeterflowmeterOval Gear MeterOval Gear Meter

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Meter

DP/Orifice

MV/Orifice

MV/Annubar

Magmeter

Vortex

Coriolis

Turbine

Fluids

Liquid,Gas,steam

Liquid,Gas,steam

Liquid,Gas,steam

Conductive Fluids

Liquid,Gas,steam

All

Liquid,Gas,steam

DirtyFluids

No

No

Some

Yes

Some

Yes

No

Viscosity

Low-Medium

Low-Medium

Low

Any

Low-Medium

Any

Low-Medium

PipeSize

0.5 - 40in

0.5 - 40in

0.5 - 72+in

0.2 - 36in

0.5 - 8in

0.5 - 6in

0.5 - 24in

MaximumPressure

6000psig

6000psig

6000psig

1400psig

1400psig

4000psig

6000psig

MaximumTemp.

175°C

200°C

200°C

PressureLoss

Medium-High

Medium-High

Low

Very Low

Low

High*

High

Flow products Flow products Summary TableSummary Table



Level 1 - Flow

63ExerciseExercise

1. Which of the following would generally provide the best turndown ?(A) DP - Orifice Plate (C) Magnetic Flowmeter(B) V.A.Meter (D) Turbine Meter

Which of the following directly measures mass flow rate, and whichvolume flow rate. Indicate “M” or “V”2. Magnetic Flowmeter [ ]3. Vortex Meter [ ]4. Coriolis Meter [ ]5. Non-compensated DP Flowmeter [ ]6. Fully-compensated DP Flowmeter [ ]

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7. The following flowmeters all create some pressure loss. Number them in order, beginning with that which create the least loss.(A) Venturi tube [ ](B) Positive displacement meter [ ](C) Magnetic flowmeter [ ](D) Vortex Meter [ ](E) Annubar [ ](F) Orifice plate [ ]

ExerciseExercise

Training - Flow

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