1. PROCESS INSTRUMENTATION Piping & Instrumentation Diagram
Mrs Anis Atikah Ahmad
Tel:

2. OUTLINE Introduction to P & ID Introduction to Process Control
Instrumentation Symbology
Instrumentation Numbering
Process Control Variety

3. PFD

4. P&ID

5. 1. Introduction to P & ID
Also known as “PROCESS & INSTRUMENTATION DIAGRAM”
Detailed graphical representation of a process (i.e piping,
equipment, and instrumentation) necessary to
design, construct and operate the facility.
Common synonyms for P&IDs include Engineering Flow
Diagram (EFD), Utility Flow Diagram (UFD) and Mechanical
Flow Diagram (MFD).

6. 1.1 Component of P & ID 2. Process Control Loop (if any)
1. All PFD components
2. Process Control Loop (if any)
3. All instruments (eg: transmitter, indicator, alarm)
4. Instrumentation Tagging & Numbering

7. 2. Introduction to Process Control
Component of Process Control
Measuring device (Sensor & transmitter)
Controller
I/P Transducer (if FCE is control valve)
Final Control Element (Control Valve, Pump, Heater)

8. 2. Introduction to Process Control
Basic Loop
Set point
Controller
Transmitter
Fluid
Fluid
Orifice (Flow Sensor)

9. 2. Introduction to Process Control
Basic Loop
Process
Sensing Element
Measuring
Element
Transmit
Control Element
Final Control
Transmitter
Sensor
Control Valve/ Heater/ Pump
Controller

10. 2.1 Sensor SENSORS (Sensing Element)
A sensor is a device that measures a physical quantity and converts it into a signal
which can be read by an observer or by an instrument.
For example, a mercury thermometer converts the measured temperature into
expansion and contraction of a liquid which can be read on a calibrated glass tube.
A thermocouple converts temperature to an output voltage which can be read by
a voltmeter.
For accuracy, all sensors need to be calibrated against known standards.

11. 2.1.1 Temperature Sensor Thermocouple Cheaper than RTD Durable
React faster to changes in temperature 
Can measure a bigger range of temperatures

12. 2.1.1 Temperature Sensor Resistance Temperature Detector (RTD)
Readings are more accurate and more repeatable
Expensive

13. 2.1.2 Flow Sensor Turbine Flow Meter
Very accurate ( commonly used to prove other meters.)
Not usable in dirty streams or with corrosive materials

14. 2.1.2 Flow Sensor Magnetic Flow Meter
Flow rate unaffected by fluid density, consistency, viscosity, turbulence, or piping configuration.
Highly accurate
Corrosion-resistant using Teflon liner and platinum electrodes
Wide flow measuring ranges & no pressure drop
   Costly, relative to other flow meter types.
   Cannot be used for gas flow measurements

15. 2.1.2 Flow Sensor Orifice Flow Meter
Fabrication simple and inexpensive.
No limitations on the materials of construction, line size and flow rate

16. 2.1.2 Flow Sensor Venturi Meter
Can be used for high/extreme temperature
Highly expensive
Larger and heavier to handle
Can be used for gas & liquid

17. 2.1.3 ASSIGNMENT
Discuss the function of each temperature and flow sensor in slide
Must include the discussion on how they operate (any principle used)
Deadline: 24 November 2016

18. 2.2 Transmitter
A transmitter measures the process variable and transmits the information to a central location where the comparison takes place
Differential Pressure Transmitter
Pressure Transmitter

19. Indicating Controller
Controller is a device which monitors and affects the operational conditions of a given dynamical system.
The operational conditions are typically referred to as output variables of the system which can be affected by adjusting certain input variables.
Recording Controller
Indicating Controller

20. 2.4 I/P Transducer
A device that converts electric signal to pneumatic signal.
Control Valve

21. 2.5 Final Control Element
Final Control Element is a device that directly controls the value of manipulated variable of control loop.
Final control element may be control valves, pumps, heaters, etc.
Pump
Control Valve
Heater

22. 2.6 Process Control Structure
Example 1
Figure below shows the liquid vessel for boiler system. The control objective in this system is to
maintain the vessel temperature at 120 oC. The heater will be switched off when the temperature
reached the desired temperature. Draw feedback control loop for the system. TC
V-100
What is the final control element in this system?
-HEATER
Fluid in TT
Fluid out
V 100

23. 2.6 Process Control Structure
Exercise 1: Draw TWO control loops to
control level L3 and L5 at the
desired level.
LT 1
LIC 1
LCV-100 close when level reached L 3
LCV-100 open when level below L3 L3
LCV-100 L2
TK-100 L1
LT 2
LIC 2
V-100 L5
LCV-101
LCV-101 close when level reached L5
LCV-101 open when level below L5 L4

24. 2.6 Process Control Structure
Answer 2
LIC 1
LT 1
LIC 1 L3
LCV-100 close when level reached L 3
LCV-100 open when level below L3
LT 1
LCV-100 L2
TK-100 L1
LIC 2
V-100 L5
LT 2
LIC 2
LT 2
LCV-101 L4
LCV-101 close when level reached L5
LCV-101 open when level below L5

25. 3. Instrumentation Symbology
Instruments that are field mounted.
-Instruments that are mounted on process plant (i.e sensor that mounted on pipeline or process equipments.
Field mounted on pipeline

26. 3. Instrumentation Symbology
Instruments that are board mounted
-Instruments that are mounted on control board.

27. 3. Instrumentation Symbology
Instruments that are board mounted (invisible).
-Instruments that are mounted behind a control panel board.

28. 3. Instrumentation Symbology
Instruments that are functioned in Distributed Control System (DCS)
- A distributed control system (DCS) refers to a control system usually of a manufacturing system, process or any kind of dynamic system, in which the controller elements are not central in location (like the brain) but are distributed throughout the system with each component sub-system controlled by one or more controllers. The entire system of controllers is connected by networks for communication and monitoring.

29. 3. Instrumentation Symbology

30. 3. Instrumentation Symbology
FC Flow Controller PT Pressure Transmitter
FE Flow Element (Orifice Plate/)
Venturi tube
FI Flow Indicator
FT Flow Transmitter LC Level Controller
FS Flow Switch LG Level Gauge
FIC Flow Indicating Controller LR Level Recorder
FCV Flow Control Valve LT Level Transmitter
FRC Flow Recording Controller LS Level Switch
LIC Level Indicating Controller
PC Pressure Controller LCV Level Control Valve
PG Pressure Gauge LRC Level Recording Controller
PI Pressure Indicator
PR Pressure Recorder

31. 3. Instrumentation Symbology
PS Pressure Switch TI Temperature Indicator
PIC Pressure Indicating Controller TR Temperature Recorder
PCV Pressure Control Valve TS Temperature Switch
PRC Pressure Recording Controller TC Temperature Controller
PDI Pressure Differential Indicator TT Temperature Transmitter
PDR Pressure Differential Recorder
PDS Pressure Differential Switch
PDT Pressure Differential Transmitter

32. 3. Instrumentation Symbology
Example

33. 3.1 Signal Line Symbology
Signal Lines Symbology

34. 4. Instrumentation Tagging & Numbering
XYY CZZLL
X represents a process variable to be measured.
(T=temperature, F=flow, P=pressure, L=level)
YY represents type of instruments.
C designates the instruments area within the plant.
ZZ designates the process unit number.
LL designates the loop number.

35. 4. Instrumentation Tagging & Numbering
LIC 10003
L = Level shall be measured.
IC = Indicating controller.
100 = Process unit no. 100 in the area of no. 1
03 = Loop number 3

36. 4. Instrumentation Tagging & Numbering
FRC 82516
F = Flow shall be measured.
RC = Recording controller
825 = Process unit no. 825 in the area of no. 8.
16 = Loop number 16

37. Various type of process control strategies
Feedback Control
Feedforward Control
Ratio Control
Cascade Control
Split Range Control

38. Feedback Control One of the simplest process control schemes.
A feedback loop measures a process variable and sends the measurement to a controller for comparison to set point. If the process variable is not at set point, control action is taken to return the process variable to set point.
Advantage: corrective action occurs as soon the CV deviates from setpoint.
Disadvantage: not provide predictive control action to compensate for the effects of known or measurable disturbance
Parameter being measured: Controlled Variable ( level of the water in the boiler)

39. Parameter being measured: disturbance variable (steam flow rate)
Feedforward Control
Basic concept: to measure important disturbance variables and take corrective
action before they upset the process.
Parameter being measured: disturbance variable (steam flow rate)

40. Feedforward Control (cont.)
Feedforward control is normally used in combination with feedback controller.
Controller with summing functions are used in these combined systems to sum up the input from both the feedforward loop and the feedback loop, and send a unified signal to the final control element.
Feedforward plus feedback controller

41. Ratio Control
Ratio control is used to ensure that two or more flows are kept at the same ratio even if the flows are changing.
FIC FF FT FT
Water
Acid
2 part of water
1 part of acid

42. Cascade control
Cascade Control uses the output of the primary controller (master) to manipulate the set
point of the secondary controller (slave) as if it were the final control element.
Used when the disturbances are
associated with manipulated variable.

43. Split Range Control
Output of a controller is split to two or more control valves.
The diagram shows pH adjustment; part of waste water treatment process. The process shall be maintained at pH 6. When the process liquid states below pH 6, CV-102 will be opened to dosing NaOH to the tank TK-100. When the process liquid states above pH 6, CV-101 will be operated to dosing HCl.
CV-102
TK-102
(base feed tank)
pHIC
pHT 1
CV-101
TK-100
(pH adjustment tank)
TK-101
(acid feed tank)

44. Exercise… Identify type of control loop used below. V-100  Y PT
PIC PT FC
V-100
Process variable need to be controlled = Pressure FT