2. Piping Fundamentals Agenda:
•Definition of Pipe and Piping
•Concept Layout Development
•
Piping Components
•
Orientation of various tapings, components, etc.
•
Piping Drains & Vents
•
Material & Sizing
3. PIPE:
It is a Tubular item made of metal, plastic, glass etc. meant for
conveying Liquid, Gas or any thing that flows.
It is a very important component for any industrial plant. And it’s
engineering plays a major part in overall engineering of a Plant.
PIPING:
The term Piping means not only pipe but also includes
components like fittings, flanges, valves, bolts, gaskets, bellows
etc.
4. In any plant various fluids flow through pipes
from one end to other.
Now let us start with a plant where we see
Three tanks: Tank-1, Tank-2 and Tank-3
We have to transfer the content of Tank no. 1
to the other two tanks.
We will need to connect pipes to transfer the
fluids from Tank-1 to Tank-2 and Tank-3
LET US PLACE THE PIPES.
5. We have just brought the pipes, now we need
to solve some more problems.
Pipes are all straight pieces.
a
es
ip
e p izes!
m
so nt s
en re
Ev diffe
of
We need some bend
connections
We need some
branch
connections
To solve these problems we need
the pipe components, which are
called PIPE FITTINGS
re
6. These are the pipe fittings,
There are various types of fittings for various
purposes, some common types are Elbows/Bends, Tees/Branches,
Reducers/Expanders, Couplings, Olets, etc.
Anyway, the pipes and
fittings are in place, but the
ends are yet to be joined with
the Tank nozzles.
We now have to complete the
end connections.
These, in piping term, we call
TERMINAL CONNECTIONS.
7. So far this is a nice arrangement.
But there is no control over the flow from Tank-1
to other tanks.
We need some arrangement to stop the
flow if needed
These are flanged joints
This is a welded joint
To control the flow in a pipe line we
need to fit a special component.
That is called - VALVE
8. There are many types of valves, categorized
based on their construction and functionality,
Those are - Gate, Globe, Check, Butterfly, etc.
Other than valves another important
line component of pipe line is a filter,
which cleans out derbies from the
flowing fluid. This is called a
STRAINER
9. Here we see a more or less functional piping
system, with valves and strainer installed.
Let us now investigate some aspects of pipe
flexibility.
This tank nozzle
expands, when
the tank is hot.
In such case we need to fit
a flexible pipe component
at that location, which is
called an EXPANSION
JOINT
10. When some fluid is
flowing in a pipe we may
also like know the
parameters like, pressure,
temperature, flow rate etc.
of the fluid.
To know these information we need to
install INSTRUMENTS in the pipeline.
11. There are various types instruments to measure
various parameters. Also there are specific criteria
for installation of various pipe line instruments.
Next we shall look into how to SUPPORT
the pipe/and it’s components.
12. Here are some of the pipe supporting arrangements.
There can be numerous variants. All depend on piping
designer’s preference and judgement.
Let us see some OTHER types of supports
13.
14. While development of piping layout we have to consider the following:
Material to withstand the high pressure and high temperature.
Piping from source to destination should be as short as possible with
minimum change in direction.
Not
Preferable
Preferable
Should not hinder any normal passage way. Also should not encroach any
equipment maintenance space.
Valves, strainers, instruments on the pipe should be easily accessible.
15. If needed separate ACCESS PLATFORMS to be provided to facilitate piping
operation.
Desired location and orientation of valves / instruments and other pipe
components are to be checked and maintained, like some valves or strainers
can only be installed in HORIZONTAL position.
Specific requirements of STRAIGHT LENGTH of pipe for some components
to be maintained, like for flow orifice we need to provide 15 D straight pipe
length at upstream of orifice and 5 D straight at down stream of orifice.
Example of Straight length requirement for Flow Orifice
16. To ensure that there is no air-trap in the pipeline, a VENT connection with Valve
is provided at the top most point of the pipeline.
A DRAIN connection with Valve is provided at the lowest point of the pipeline
for liquid drain from pipeline.
Pipes are also slopped towards low points.
Let us look
into typical
Vent and
Drain
arrangement
in a pipeline
17. Provision to be made to absorb thermal expansion in pipes during high
temperature applications.
Avoid Piping load transfer to applications- with suitable supports and
anchors.
Underground / Embedded piping issues.
Insulation / Freeze protection issues
There are many recognized international codes which lay down guide
lines and mandatory requirements for design of piping.
Most followed standards are:
ASME ANSI B31.1- Power Piping Code &
IBR - Indian Boiler Regulation (in INDIA)
18. Pipe Material Selection - to select appropriate pipe material based on flowing fluid property.
Find out type
of Fluid
flowing
Find out
Fluid Temp.
& Pressure
Check Pipe
life
Expectancy
Select suitable
Material per
practice (Note-1)
Check Mat.
Listed in
Design Code
YES
Pipe
Material
OK
NO
Note-1 : Material is selected per past experience with cost in mind
and per material listed in design code. If material is not listed
in code we may select next suitable material listed.
See Note-1
Pipe Sizing Calculation - to select required pipe diameter based on velocity and pressure drop.
Find out
Flow volume
per second
Check Velocity
Allowable per
second
Calc. flow area
required and
Pipe size
Calc. Press.
Drop for that
Pipe size
Check Press. YES
Drop meets
Press. Budget
Pipe
Size
OK
NO
Increase
Pipe Size
Pipe Thickness Selection - to select appropriate pipe thickness based on flowing fluid property
Select Mat.
& Diameter
as above
Find out
Fluid Temp.
& Pressure
Decide on
Corrosion
allowance
Calc. Pipe
Thickness per
Code
19. We have just completed a pipe line design. How Piping design is done in
practice?
Determine the Flow scheme:
1) What,
2) From what point,
3) To which point
Selection of Pipe material, Pipe sizes and Pipe wall thickness are selected.
Selection of suitable Valves and fittings wrt functions required
Instrumentation required
All of the above are represented in a drawing which is called Piping and
Instrumentation Drawing, in short P&ID. This drawing contains all the
information about a pipe like, Pipe size, Flowing Fluid, etc.
21. After the P&ID is ready, the layout work, pipe routing / layout is generally
done in a Virtual 3D environment using a customised software. This is called
as Piping modeling or Physical design.
3D drawing of a Typical piping system