Instrumentation

AUTOMATION

Control Measurement

Temperature Measurement

Pressure Measurement

Tank gaugingMeasurement

Flow MeasurementFeed

Back

Programmable Logic Control

SCADA

DCS

Profi – Bus

ASI Protocol

P r e s s u r e

T a n k G a u g i n gM e a s u r e m e n t

T e m p e r a t u r e

F l o wM e t e r i n g S y s t e m s

P r e s s u r e

P r e s s u r e - D e fi n i ti o n

Pressure is the FORCE per Unit AREA

ghA

FP

Pressure is Directly proportional to the Material (Liquid – Gas)

Density & Height in the Storage Container


Pressure Measurement

??WHY HOW

Pressure is measured for the following:

Level

Flow

Checks

P r e s s u r e Measuring Device

Pressure Transducer

Element that converts the pressure into Mechanical

Electric Value

Pressure Transmitter

Element that converts the

value to 4-20mA Signal


P r e s s u r e REFRENCEs

Absolute Gage Differential

P r e s s u r e - I n d i c a t o r s

P r e s s u r e

Indicators

Bourdon Tube

PigtailSiphon

DiaphragmGage


Bourdon T u b eConsist of a Bent Oval Tube

• One End connected to the PROCESS PRESSURE

• The other End to the Mechanism operating the POINTER

As the pressure increase the Tube tend to become CIRCULAR from OVAL

This movement is detected by the POINTER MECHANISM


Diaphragm G a g e

NO PRESSURE

NO PRESSUREDIAPHRAGM

PRESSURE

Diaphragm

The Diaphragm is EXPOSED to the PROCES RESSURE

This will make the Diaphragm to BEND Over

This bending is detected by the pointer mechanism which detects the pressure

15 psig

15 psig DIAPHRAGM

PROCESSPRESSURE


P i g - Ta i l S i p h o n

This INDICATOR usually used in measuring the STEAM Pressure

The Oval Path is for:

• Condensing the vapor

to insure that the steam

wont reach the measuring

Element.

• Isolating the HOT VAPORS

from the measuring

elements

P r e s s u r e - S w i t c h

P r e s s u r e

S w i t c h

Monitoring Pressure

Take Action due to the Measured Pressure

PRESSURE SWITCH

RELAY ELECTRIC SOURCES

ELECTRIC EQUIPMENT

I.O. PUMP ANNUNCIATOR

PROCESS PRESSURE

P r e s s u r e - S w i t c h

PressureS w i t c h

Consist of

WHENThe Pressure reaches a certain Limit the Switch sends an Electrical Signal indicating that the Pressure reached a certain Limit.

Pressure Measuring Device Element

Electrical System or Contact

WHY ??

This Electrical Signal is sent to a RELAY or PLC input to START/STOP an operating Equipment ( PUMP – ALARM – VALVE – PROCESS )

P r e s s u r e - Tr a n s m i tt e r

P r e s s u r e

Transmitter

Capacitance Piezoelectric

Differential

C a p a c i t a n c e P r e s s u r e Tr a n s m i tt e r


d

AC o

d

The process pressure actives 2 Diaphragms & these 2 diaphragms acts as 2 Plate Capacitors

When the pressure occur the diaphragm will bend over causing that the space (d) to increase .

The thing will affect the capacitance

The capacitance value is measured by electronic circuits to represent the pressure

P i e z o e l e c t r i c P r e s s u r e T r a n s m i tt e r


Is a material that :• Generates Voltage when exposed to Pressure• Generates Pressure (Vibration) when exposed to

Voltage

The Piezoelectric Pressure IndicatorWhen applied to process pressure this affect a diaphragm that apply a FORCE to a Piezoelectric Material.

The Piezoelectric material produces a voltage corresponding to the applied force

D i ff e r e n ti a l P r e s s u r e Tr a n s m i tt e r


Is a device that compares

between 2 input pressures

and sends the NET pressure

21 PPP

P r e s s u r e




Te m p e r a t u r e - D e fi n i ti o n

Units of Measurements

Temperature Elements usually saved in a THERMOWELLTo protect the element – since its FRAGILE

• Fahrenheit scale• Celsius scale• Kelvin (used mainly for scientific work)

Conversions

15.273

32)5

9*(

KC

CF

The THERMOWELL is not required in some applications• Internal of some EQUIPMENTS• Bearings

Temperature Measurement

??WHY HOW

Temperature is measured at the following:

Boilers

Tanks

Pumps Bearings

… etc

Te m p e r a t u r eMeasuring Device

TemperatureTransducer

Element that converts the temperature into Mechanicalor Electric

Value

TemperatureTransmitter

Element that converts the

value to 4-20mA Signal

Te m p e r a t u r e - D e fi n i ti o n

Te m p e ra t u re

Indicators

ThermocoupleResistance

Temperature Detector

Te m p e r a t u r e - I n d i c a t o r s

Thermocouple

2 Metals 2 Junctions

Immersed in a Liquid and

1 Reference Junction

Immersed in ICE or left in AIR


N

n

nnVaT

0

Self PoweredShock Resistance

InexpensiveThey Provide fast Response (in Seconds)

Non-Linear outputLow Voltage

Require a Reference JunctionLOW Sensitivity & Accuracy

Advantages Disadvantages

Resistance Temperature Detector

Pure Metals will produce an

Increase in Resistance

Increase in Temperature


T

T

qo

o

TRTR exp)(

T

Ro - To

ρ

Temperature

Material Parameters ((Constants))

= 0.5 ((Coefficient for fine tuning & calibration))

Most Known Example is

PT100

Material got an Electrical Resistance Coefficient = 100Ω

at ZERO Celsius



H o w

it WORKs

2-Wire Connection 3-Wire Connection

4-Wire Connection



Most StableMost Accurate

SensitiveLinear

Require no REFERENCE

ExpensiveRequire Current source

Have Limited Temperature RangeAccuracy Varies with Temperature

Advantages Disadvantages

Ranges of:

-200 – 500 Celsius (RTD)

Larger Range (Thermocouple)

Tolerance of:2 Celsius Or greater

Thermocouple

Less than 2 Celsius RTD

Temperature

When to use ??According to some Factors such as:

Very Fast Response(RTD) Frictions of Sec.

Larger Range(Thermocouple) Sec.

Time Accuracy

Tight Places RTD

Large Places Thermocouples

Size

P r e s s u r e




Ta n k M e a s u r e m e n t - D e fi n i ti o n

T a n k M e a s u r e m e n t s

We deal with …

Level Measurements Temperature Measurements

Automatic Tank Gauging

Radar Tank Gauging

Sopot

MRT

MTT

Ta n k M e a s u r e m e n t - AT G

A u t o m a ti c T a n k G a u g i n g

TERMINAL COMP.

ELECTRONICCOMPARTMENT

DRUMHOUSING

Drum Housing

Electronics

XPU

SPU

OptionPowerF

W

B

Consist of:

1. Floating Displacer

2. Drum + Stepper Motor

3. Force Transducer

4. Electronics

F l o a ti n g D i s p l a c e r


T h e o r y of Operation


If the Liquid level go UP & DOWN This tension differs than Specific Value

Here the Micro-Processor takes the decision to start Rotating the Stepper Motor Connecting to the DRUM to move the displacer upward or downward till the force transducer measures the specific value

Numbers of Revolutions done by the stepper motor is equivalent to the level

DRUM

FORCETRANSD

UCER

CONTROL ELECT.

MOTORCONTROL

WEIGHTMEAS

MOTOR

APPARENT WEIGHT

The displacer is placed into the Container on the Liquid surface

The cable holding the displacer got a specific Tension detected & measured by the Force Transducers

Ta n k M e a s u r e m e n t - R T G

R A D A RT a n k G a u g i n g

Radar is an excellent technology to locate 'invisible' objects

distance of object is located using radio waves

Level measurement is distance

measurement radar technology is

adapted for accurate level measurement

inside storage tanks

distance dt

antennaobject

oscillator detector

t t

tt

f

am

pl.

Elapsed time Dt is measured

Time Dt = 2d / C

Example Dt = 50 msd = ½ · 50·10-6 · 3·108 = 7500 m

Conclusionpulse radar is not suitable for high accuracy on short distances


P r i n c i p l e s of pulse Radar

Saab TankRadar is a powerful radar level gauge suitable for non-contact level measurements in process tanks, storage tanks and other types of tanks.

The modular hardware and software design makes it possible to specify a TankRadar Pro gauge that will meet your requirements.

It can be used as a stand-alone unit, or it can be connected to various control systems.

You can integrate TankRadar Pro in your own Local Area Network (LAN).

By using the Saab TRL/2 Bus interface you can easily connect Pro gauges to a Saab TankRadar L/2 supervisory system.

I n t r o d u c ti o n



I n t e g r a t e d Tank Gauging System

Spot MRT MTT

+ low cost+ simple &

+ aver. prod. temp. + vapour temp.

reliable

+ aver. prod. temp.+ vapour temp.++ sturdy & reliable++ temp. profile

R0......R11 R t

R t Tn

Un

Te m p e r a t u r e E l e m e n t s

T a n kTemperature Measurement

Ta n k M e a s u r e m e n t - Te m p e r a t u r e

TCF

TCE

TCD

TCC

TC4

TC3

TC2

TC1

TC0

Pt100

CuNi

constantane (CuNi)

shrink sleavesolder connection

copper (Cu)

M T T C o n s t r u c ti o n


area not measured by MRT

i

MRT MTT

± 0.2 °C ± 0.1 °C

level

± 0.1 °C± 0.5 °C

M T T V. S M R T


P r e s s u r e




T u r b i n eM e t e r s

M e t e r C o n st r u c ti o n

A Rotor attached to:

Bearing

& Shaft

Tu r b i n e M e t e r s - C o n s t r u c ti o n

RotorConsist of a group of Blades fixed at a specific angle causing rotation when the fluid stream

Less than 6” Meter Types

Larger Meters Types

F o r

Open Bladed made of

Stainless SteelOr

Ferro Magnetic Material

Rimmed RotorsWHY?

To increase the PULSE resolution by adding more detection points

per rotor revolution


Bearingis a Hard Surface Journal

Good Bearing is IMPORTANT

Why ??

Long Service Life

Good Repeatability

Good Accuracy


Counting PulsesCoil Many thousands turns of fine wire wrapped around a ferromagnetic material

The rotor rotates due to flow & the Coil + Magnet counts the magnetic buttons & send these pluses to the AMPLIFIER to amplify the signal…

Tu r b i n e M e t e r s – P u l s e C o u n t e r

M e t e r Performance Curve

Tu r b i n e M e t e r s

F a c t o r s Affecting Meter Accuracy

Cavitations

Velocity Profile&

Swirl


F l o wConditioning


Ty p i c a lMetering Line

Outlet Valve

Prover Valve

Control ValveTurbine

Meter

Strainer & Air Separator

Inlet Valve P T

Pressure Relief Valve


P DM e t e r s

P D M e t e r s

PD Meters Directly Measure Volume by

Counting Rotor Revolutions

V o l u m eMeasurement Principles

• Measure Liquid Volume

• Produce Torque to Drive Meter Accessories

F u n c ti o nOf Measuring Element

F L O WP r o fi l e

P D M e t e r s

Inner mechanism Housing

ShaftRotor Gear

Measuring Chamber

Rotor

Retracting Blade

ExtendedBlade

P D M e t e rI n n e r M e c h a n i s m

P D M e t e r s

Instrumentation

Documents

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