π " Three Times Better (Engineer) "
The 3 Things You will learn today are as follows.
β’ One Engineering Learning
β Why ISA and IEC Valve Sizing Standards can help you solve any damn sizing problem.
β’ One Engineering Question
β What Standard to Use for 2 Phase.
β’ One Career Tip from Top Professionals
β How I remember stuff (Secret make it interesting)
#1 -Engineering Learning
Most Engineers are scared of "Control Valve Sizing".
If feel because it is too complex.
We enginers are not easily replaceble by A.I (as of now)
Today I will like to share how valve sizing can be easy
With the help of engineering standards.
Let's jump into it.
If you need to size a valve
First understand the concepts in the standard.
You donβt need to memorize the equations.
Thatβs Dumb.
I agree.
But the Valve Sizing Standards are not random.
Each standard is your Golden Solution
To a problem you encounter in sizing.
Understand the exact engineering problem first.
Then apply the precise standard.
I will now share a Step-By-Step Algorithm.
That will make your engineering life easy.
First Question : What is the Fluid Phase.
Your Control Valve needs to control Process Fluid.
So, you need to know your fluid
Is your fluid
β’ Liquid
or
β’ Gas?
This is your first major decision.
Next, analyse the internal fluid friction.
Second Question : Is the Fluid Sticky.
Is the flow smooth or sticky?
You must check the Reynolds Number.
β If Reynolds is over 10,000
β’ For liquids, use ISA 75.01.01 Section 6.β
β’ For gases, use ISA 75.01.01 Section 7.β
If you are using your software correctly select the phase
What if you have dual phase ?
For that Askik Azarudeen had rightly answered in last weekβs email
But you can learn more in the βEngineers Guide to Control Valve Sizingβ
β If Reynolds is under 10,000
Means the fluid is highly viscous (Think something like Honey)
Standard sizing equations will completely fail.
You must use ISA 75.01.01 Appendix A.
The Sound Problem Solution
Valves drop process pressure very rapidly.
This creates severe vibration and sound.
You must predict and control this.
You need the correct Noise Standard.
Again, look at your fluid state.
β If controlling Gas (Aerodynamic noise)
β If controlling Liquid (Hydrodynamic noise):
The Cavitation Problem and Solution
Pressure drops cause boiling liquid bubbles.
These bubbles collapse and destroy metal.
This is the danger of Cavitation.
You must thoroughly evaluate this risk.
In the βEngineers Guide to Control Valve Sizingβ
We have a detailed algorithm as per ISA RP 75.23β
Too dificult to cover it here.
But I promise will be worth it.
The Valve Testing Standards
Now we know,
There are various flow characteristics.
- Eq %
- Linear
- Quick Opening
What if your valve is a custom built valve
How will you ensure that
- Valve has Correct CV (Flow Capacity)
- Valve has Correct Inherent Flow Characteristic
Here these standards help.
The vendor finally built your valve.
But does it actually perform correctly?
You must verify the total flow capacity.
And You must also test the flow curve.
You need the CV Test Standard.
β’ For the capacity testing procedure
β Use standard IEC 60534-2-3.
β’ For the flow characteristics testing
β Use standard IEC 60534-2-4.
Now you see the complete picture.
You map engineering problems.
You assign the exact standard required.
This builds a perfect mental map.
If you like Mind maps and Algorithms,
You will love the βEngineers Guide to Control Valve Sizingβ
If you Want 26 Point Excel on Control Valve Sizing
Reply "Control Valve Sizing Excel Checklist"
And I will share it with you immediately. (Since it is ready)
#2- Engineering Question
π Let us Geek Out.
Can you tell me which IEC or ISA standard is used
For 2 phase control valve sizing ?
The one who rightly answered this the first was.
Here's his linkedin profile (If you like networking)
Answer : There is no standard.
Neither ISA not IEC can help direclty in 2 Phase.
You can read "Engineers Guide to Control Valve Sizing" for understand what are the methods for 2 Phase Sizing cases.
(Too Difficult to cover all the methods in this article).
Question of the Week
If I have a Dirty Service (Particle Size greater than 30) and Differential Pressure of 80 Bar and its green field project.
What Type of Control Valve Should I select
- Angle Valve
- Butterfly Valve
- Multi Path Control Valve
- Multi-Stage Control Valve
- Diaphragm Type Control Valve
Right Answer and the person will be featured next week.
Want to be a Control Valve Subject Matter Expert in your company.
ACV is currently sold out.
But you can Hop on the Waitlist of ACV 2026 here.β
#3 -Career Tip
Think of your favorite childhood movie.
You likely remember every single scene.
Did you actively try to memorize it?
No, you just felt strong emotion.
The significance makes it entirely permanent.
Fav Movie Method to learn.
Let's apply this to our learning.
Do not just memorize standard codes.
Do not just read the equations.
Find out why they actually exist.
What massive disaster did they prevent?
Suddenly, learning becomes completely effortless.
β Always find the underlying reason.
β Attach a strong consequence or meaning.
In simple words "Learn with INTEREST" and your brain will remember.
If you learn just to keep your job.
I think its a recipe for copy-paste engineer.
But since you are reading this newsletter means you are interested to learn and buld yourself into a powerful engineer.
Proud of you !!
Keep learning and Growing to be World Class Engineer!!
How was today's learning
- Highly Valuable : Reply 1
- Somewhat Valuable : Reply 2
- Needs Improvement : Reply 3
I see each feedback reply as a gift.
Until next week,
Happy Learning & Keep Smiling.
Asad Shaikh
Your Instrumentation Friend!! π
See you next week!
PS: If you would like 23 Point Control Valve Sizing Excel Checklist then please reply "Sizing Checklist" and I will share the same with you instantly.
β