process flow diagram (pfd) & process and instrumentation diagram (p&id)

8/10/2019 PROCESS FLOW DIAGRAM (PFD) & PROCESS AND INSTRUMENTATION DIAGRAM (P&ID)

1/29

CBB1052 ENGINEERING

GRAPHICS

PROCESS FLOW DIAGRAM (PFD)

& PROCESS AND INSTRUMENTATION

DIAGRAM (P&ID)

CHAPTER 9

WEEK 11


2/29

OBJECTIVES

At the end of this lecture, students should be able

to:

Explain what is PFD and P&ID

Construct PFD given a process statement or from

block diagram

Understand and apply general draughting rules


3/29

(B) PROCESS FLOW DIAGRAM

In the process flow diagram (PFD), processes

and/or process plants are shown as graphical

symbols, interconnected by flow lines.

The graphical symbols represent equipment and

the lines represent flows of mass or energy or

energy carriers.


4/29


The process flow diagram should consist of the

following basic information:

symbols of process equipment

denomination of the equipment

route and direction of the incoming and

outgoing material, energy and/or carrier flows

denomination of flows of incoming and outgoing

materials, energy and/or carriers

operating conditions (T and P)


5/29


Source: EN ISO 10628:2001

Symbols of process equipment

Denomination of the equipment

Route & direction of incoming & outgoing material

or energy flows

Operating conditions

Denomination of flows of incoming & outgoing

material

or energy flows


6/29


The process flow diagram may also contains:

denomination of flow directions and flow rates

of process fluids between the process steps

essential valves in the logical process position

with respect to their function

functional demands for process measurement

and control at essential points


7/29


(continued):

supplementary operating conditions ( , )

denomination of equipment and characteristic

data of equipment

denomination of drives (e.g., gears, conveyors,

belts, chains, cranes) and their characteristics

elevation of platforms and approximate

relative vertical position of equipment.

Density, viscosity


8/29


Source: EN ISO 10628:2001

Data tables

Supplementary operating conditions ()

Operating T & P

Gate valve

Elevation of platforms &

approx relative vertical position of equipValves in the logical process position

with respect to their function

Flowrates of process fluids

Functional demands for process measurement

& control


9/29

(C) PROCESS ANDINSTRUMENTATION

DIAGRAM(P&ID)

The piping and instrumentation diagram (P&ID) is

drawn based on the process flow diagram (PFD).

The P&ID represents the technical realization of aprocess by means of graphical symbols for equipment and

piping together with graphical symbols for process

measurement and control functions.


10/29

The piping and instrument diagram should consist of the following

basic information:

function or type of equipment, including drives,

conveyors as well as installed spares

identification number of equipment

characteristic data of equipment

indication of nominal diameter, pressure rating,

material and type of piping


DIAGRAM(P&ID)


11/29


12/29


13/29


DIAGRAM(P&ID)

The piping and instrumentation diagram may also contains:

denomination of flow rates or amounts of energy or energy

carriers

route and direction of flow of energy or carriers

type of essential primary elements and sensors

essential construction materials for equipment

elevation of platforms and approximate relative verticalposition of equipment

reference designation for valves and fittings

denomination of equipment


14/29


15/29

EQUIPMENT DENOMINATION ACCORDING

TO BS

K1 Bubble cap tray column

W1 Circulating evaporator

W2 Condenser

W4 Distillate cooler W5 Residue cooler

B1, B2 distillate vessel

P1A-B Centrifugal pump

P2A-B Pump

P3A-B Centrifugal pump


16/29

EQUIPMENT FUNCTION CODE BASED ON

PTS


17/29

EQUIPMENT FUNCTION CODE BASED ON

PTS


18/29


19/29

Process & eng flow scheme Utilities & eng flow scheme


20/29

DCS=distribution control system


21/29


22/29

GENERAL DRAUGHTINGRULESACCORDING

TOBRITISHSTANDARD

Dimensions

Should reflect the actual relative dimensions with

respect to scale and elevation (exclude valves,

pumps and measurement unit)

Location

Devices to be expected at the uttermost level of the

plant shall appear at the top of the drawing

Those devices at the lowest level are expected to be

shown at the bottom of the drawing Logical position


23/29


24/29

Flow Direction

Flow direction shall start from left to right or topto bottom

Line Spacing

Line should not be spaced less than twice thewidth of the lines

Line spacing (parallel lines) > 10 mm is highlydesirable

Arrows

For better understanding, arrow may be located atthe inlet of the equipment and upstream of pipebranches


TOBRITISH STANDARD(CONT.)


25/29



Lines Connection


26/29



Auxiliary system lines

Lines shall be shown as dashed lines with the

indication of the direction of flow and reference to

type of the energy carrier

Lettering Height of letters shall be 5 mm for reference

designations of major equipment

2.5 mm for other inscriptions


27/29

INSTRUMENT NOMENCLATURE


28/29

SUMMARY

PFD

P&ID

General Draughting Rules


29/29

process flow diagram (pfd) & process and instrumentation diagram (p&id)

Documents