Tube rupture is an unwanted phenomenon in Process Industries. Here, we take a look at that along with other terminologies in Chemical Engineering

1. Amir Bashir
E11-15 PG 11

3. Table of contents
Tube Rupture
◦ Line of action…………………………………………..
◦ Why it occurs…………………………………………..
◦ Stages………………………………………………….....
◦ How to avoid…………………………………………..
Battery Limits:
◦ Usage in industries………………………………..
◦ Pictorial representation…………………………
Personal protective equipment
◦ Types of Hazard………………………………….
Air Sox

4. Tube Rupture
When a tube breaks down due to conditions that are
considered haphazard, such a definition is known as tube
rupture. It can be defined in two ways
a) The tube failure is a sharp break in one tube.
b) The tube failure is assumed to occur at the back side of the tube sheet.

5. A Picture is always worth a thousand
words!

6. Line of action
Heat Exchanger

7. Why it arises?
High and Low pressure zones contribute
Significantly to tube rupture!

8. 1. When there is a significant pressure difference
between the shell and tube side of the heat
exchanger
2. When the high pressure zone exceeds a pressure of
1000psig
3. If the high pressure side contains a liquid or a vapor,
that may vaporize and can result in the subsequent
vaporization of the liquid on low pressure zone.

9. Stages of tube rupture

11. 2/3rd rule
It states that:
◦ If pressure on the low pressure side is greater than or
equal to 2/3rd of the pressure on the high pressure side,
there is negligible danger of tube rupture

12. If we apply 2/3rd rule on this pipe, then it is NOT dangerous
when it comes to tube rupture

13. 10/13 rule
It states that:
◦ If pressure on the low pressure side is greater than
or equal to 10/13 on the high pressure side, then
the risk of tube rupture can be ignored

14. If we apply 10/13 rule on this pipe, then it is NOT dangerous
when it comes to tube rupture

15. Hydro-static test
This test is basically used to minimize the tube
rupture characteristic of the pipe.
It is carried out before the tube or pipe is used in a setting i.e. that of
heat exchanger.
It is used to test pipelines, gas cylinders, boilers for strength
and leaks

16. 1. The tube is filled with a
incompressible liquid i.e. water
2. One side is closed while water is
filled through other side
3. Pressure is increased above the
design pressure
4. After Pressure is achieved, supply
valve is closed and Pressure monitored
5. If there is a decrease in Pressure, it
will indicate some sort of leakage
6. By doing this, we can determine
leakage, strength and location of leakage

17. Steps
1. Analysis of the heat exchanger should be carried out
considering the tube vibration, tube wall thickness.
2. Usage of PSV’s
3. The design pressure of the heat exchanger should be increased
if it is operated at high pressure in order to mitigate tube
rupture
4. If possible, it is best to keep the low pressure fluid on the shell
side.
5. Usage of a vapor pocket on low pressure side

18. Battery Limit
Areas which are specifically designated to different departments in a
refinery or a chemical plant is known as battery limit.
This is more often than not, a physical boundary, that is used to
differentiate the process units from the supporting equipment
Battery limits help to define the role of an engineer by
making him know that which task he is expected to do, in
which area of the industry

19. Pictorial representation

20. Personal Protective equipment
Personal protective equipment's or PPE’s, are the devices that
are used for safety not only in the industries, but everywhere.
Since the introduction of safety standards i.e. OHSAS, PPE’s have
become an integral part of modern industries.
Their basic purpose is to reduce the hazards to which, the
employees will be exposed in engineering works

21. Need to protect!

22. Types of Hazards

23. Regulations:
1. Properly assessed before usage to make sure it is suitable for the
purpose
2. Maintained and stored properly
3. Provided with instructions on how to use it safely
4. Used correctly by employees

24. Limitations:
1. discrepancy between theoretical and actual levels of protection
provided exists
2. only effective if correctly selected, fitted, used, and cared for, and
the individual is trained.
3. the choice of PPE may compromise mobility, visibility,
communication

25. Air Sox
Air Sox, or in common language known as wind sox, are used to
determine the direction of air flow.
It is designed to indicate wind direction and wind speed.
Wind-speed is indicated by the wind-sox’ angle relative to the
mounting pole.
They are typically used at gas plants and airports

26. Ok with the wind
direction, but how
can it indicate the
wind speed?

27. Here it is!
According to the Canadian transport standards, a 15KN wind
will fully extend the wind-sox.
A 10KN wind, will extend the wind sox to about 5* below the
horizontal.
And a 6KN wind, will extend it to 30* below the horizontal.