Overview of Piping and Instrumentation / Process Flow Diagram 3 Levels of Diagram The Block Flow Diagram (BFD) Definitions of BFD PFD Drawing Symbols The Process Flow Diagram P&ID – Construction Bible

1. Overview about Piping and Instrumentation /
Process Flow Diagram

2. 3 Levels of Diagram
 Block Flow Diagram (BFD)Block Flow Diagram (BFD)
 Process Flow Diagram (PFD)Process Flow Diagram (PFD)
 Piping and Instrumentation Diagram (P&ID) – oftenPiping and Instrumentation Diagram (P&ID) – often
referred to as Mechanical Flow Diagramreferred to as Mechanical Flow Diagram
ComplexityComplexity ConceptualConceptual
increasesincreases understandingunderstanding
IncreasesIncreases
As chemical engineers, we are most familiar with BFDAs chemical engineers, we are most familiar with BFD
and PFD.and PFD.

3. The Block Flow Diagram (BFD)
 BFD shows overall processing picture of aBFD shows overall processing picture of a
chemical complex.chemical complex.
 Flow of raw materials and products mayFlow of raw materials and products may
be included on a BFDbe included on a BFD

4. Definitions of BFD
 Block Flow Process DiagramBlock Flow Process Diagram
 Similar to sketches in material andSimilar to sketches in material and
energy balancesenergy balances
 Block Flow Plant DiagramBlock Flow Plant Diagram
 Gives a general view of a largeGives a general view of a large
complex plantcomplex plant

6. PFD Drawing Symbols

7. The Process Flow Diagram (cont’d)
Table 1.2 : Conventions Used for Identifying Process EquipmentProcess Equipment General Format XX-YZZ A/B
XX are the identification letters for the equipment classification
C - Compressor or Turbine
E - Heat Exchanger
H - Fired Heater
P - Pump
R - Reactor
T - Tower
TK - Storage Tank
V - Vessel
Y designates an area within the plant
ZZ are the number designation for each item in an equipment class
A/B identifies parallel units or backup units not shown on a PFD
Supplemental Information Additional description of equipment given on top of PFD

8.  XX-YZZ A/B/…XX-YZZ A/B/…
 XX represents a 1- or 2-letter designationXX represents a 1- or 2-letter designation
for the equipment (P = pump)for the equipment (P = pump)
 Y is the 1 or 2 digit unit number (1-99)Y is the 1 or 2 digit unit number (1-99)
 ZZ designates the equipment number forZZ designates the equipment number for
the unit (1-99)the unit (1-99)
 A/B/… represents the presence of spareA/B/… represents the presence of spare
equipmentequipment

10.  Equipment are identified by number and aEquipment are identified by number and a
label (name) positioned above thelabel (name) positioned above the
equipment on the PFDequipment on the PFD
 Basic data such as size and key data areBasic data such as size and key data are
included in a separate table (Equipmentincluded in a separate table (Equipment
Summary Table)Summary Table)

11. VesselVessel V-101V-101 V-102V-102
Temperature (ºC)Temperature (ºC) 5555 3838
Pressure (bar)Pressure (bar) 2.02.0 2424
OrientationOrientation HorizontalHorizontal VerticalVertical
MOCMOC CSCS CSCS
SizeSize
Height/Length (m)Height/Length (m) 5.95.9 3.53.5
Diameter (m)Diameter (m) 1.91.9 1.11.1
InternalsInternals s.p. (splash plate)s.p. (splash plate)
A Section of Table 1.7: Equipment Summary

12. P&ID – Construction BibleP&ID – Construction Bible
 Contains: plant construction informationContains: plant construction information
(piping, process, instrumentation, and other(piping, process, instrumentation, and other
diagrams)diagrams)

16. Section of Plot Plan Section of Elevation Diagram

17.  Piping Isometrics – show piping in 3-Piping Isometrics – show piping in 3-
dimensionsdimensions
 Vessel Sketches – show key dimensions ofVessel Sketches – show key dimensions of
equipment and locations of inlet and outletequipment and locations of inlet and outlet
nozzles etc.nozzles etc.
 Pipe and Valve Schedule.Pipe and Valve Schedule.

18.  Now virtual or electronic models are generatedNow virtual or electronic models are generated
using software (3-d plant diagrams)using software (3-d plant diagrams)
 Purpose of Models – catch errors such asPurpose of Models – catch errors such as
 Piping clashesPiping clashes
 Misaligned pipingMisaligned piping
 Equipment not easily accessedEquipment not easily accessed
 Sample points not easily reached by operatorsSample points not easily reached by operators