Article Contents
Pipe Line sizing calculations is very important being a chemical engineer or project engineer or a piping engineer.In this article we study about how to #piping sizing calculations for steam, cooling water and air. In chemical industry we need to do line sizing for verius application like DM #water transfer , cooling water, solvent transfer etc.
Pipe Line sizing calculations
As a chemical engineer or piping engineer we need to do piping sizing calculations for,
- cooling water line sizing
- Chilling brine
- Chilling water
- Air line
- Nitrogen line
- Hydrogen line
- Steam line sizing
- High therm oil piping
- DM water piping
- Process piping
cooling water line sizing
In chemical, pharmaceutical, dyes and pigment industries cooling water is very common in use. Being a process or project engineer we need to do line sizing for cooling water system.
Basic formula for calculations of coling water pipe sizing is,
Flow = Area x velocity
Q (M3/Sec) =A(M2) x v (M/Sec)
so required diameter for cooling water line,
A= Q/v
0.785xD^2=Q/v
D =√[Q/(v x 0.785) ] , whre D is in meter.
We can do line sizing using above equation.
To do pipe sizing we need to consider the velocity.
Velocity @ pump suction for water –
0.5 M/Sec to 1 M/Sec
Velocity @discharge of pump
1.5M/Sec to 3 M/Sec
Example no 1 :- Calculate the sizing of pipe required to pump cooling water at flow 10 M3/hr.
solution.
First we need to convert this M3/Hr flow in to M3/Sec by dividing 3600.
Flow = 10/3600 M3/Sec
Choose velocity, 2 M/Sec
Now required diameter = √(10/3600) /2*0.785 M
diameter = …………..M
PLEAS do calculations and comment below. I will verify.
Steam line sizing
There are three types of steam available in industry.
- Low pressure steam (LP steam)
- High pressure steam (HP steam)
- Super saturated Steam
In Low pressure steam pressure is below 4 bar, and in high pressure steam pressure is above the 10 bar.
By using density of steam @perticular temperature and pressure we need find out steam density. For this we can use steam table. From steam table we can easily get steam density at our required temperature and pressure.
What is formula for calculation of steam line sizing.
we can use same formula for steam pipe sizing calculation as like cooling water piping sizing calculations.
Flow = velocity * cross sectional area
where we can use different velocity as per pressure.
for LP steam velocity is, 20 to 30 M/Sec.
For High pressure steam, 30 to 50 M/sec.
Which pipe is use for steam flow???
We need use IBR pipes for steam. It is not necessary to use IBR pipes for Low pressure steam, but if we want we can use it.
Some important things About piping
In piping design line sizing is just one part, apart from it we need to some other things. Like piping MOC salection, Schedule number salection, seamless/ERW/IBR, Piping size etc.
In Piping design we need give following specifications as a chemical engineer.
- Pipe size
- Pipe Schedule number
- ERW/Seamless/IBR
- Pipe MOC
If you need more information regarding above specifications you can comment in below comment box.
Area formula = (pi/4) * square of diameter.
Applications of piping Sizing
The main applications are,
- We can do process piping design, we can prepare PID
- We can do piping design for utility
- We can do piping design for vapours too.
- We can do piping design for gases.
- We can do PID for utility.
Conclusion
Above article clearly gives idea about cooling water line sizing, steam line sizing, air line sizing.To do line sizing basis formula is flow is equal to velocity x cross sectional area.We need salect velocity as per required pressure drop.Also this article gibes idea about piping specifications which is necessary to purchase pipe. To purchase new pipes we need to specify it’s MOC, Schedule, size and type like IBR, Seamless or ERW.
Please comment and Do share,,,,,,……. Thank you
Read Also,
Different types of pump used in chemical industry
Good idea