High Pressure Storage
Of
Permanent Gases

Everest Kanto Cylinder Limited

P.M.Samvatsar
Need for High Pressure Storage
need to store, handle and transport higher quantity of
gas in containers that are manageable.
Higher the pressure, larger is the quantity of gas contained
in same cylinder volume.
Lighter the cylinder, more convenient and economical it is to
handle it and transport it.
Larger cylinders banks offer less joints to make leak proof.
There are certain requirements which just cannot be
serviced by liquefied gases.
Everest Kanto Cylinder Limited
P.M.Samvatsar
We
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Why not Liquefied Gases?
the liquefied gases containing, conveying and
transportation is full of limitations which have so far kept them
away from being universal solutions.
They call for specialized cryogenic vessels which need to be
continuously monitored.
They also need special care while handling, unlike gas
cylinders. This calls for persons with special training and skills
If the offtake of gas from cryo vessel is lower than the gas
being generated due to heat seepage then the gas has to be
released with resultant wastage. Such release is not possible
for flammable gases.
So, there are majority of applications where only
compressed gas cylinders are suitable.
Everest Kanto Cylinder Limited
P.M.Samvatsar
Usually
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Everest Kanto Cylinder Limited
P.M.Samvatsar
Why not Liquefied Gases?
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Everest Kanto Cylinder Limited
P.M.Samvatsar
Efficiency of Cylinders
word Efficiency is used in cylinder industry for the
amount of gas content for unit weight of cylinder.
So, cylinders which can contain higher pressure for lower
weight are more efficient. They reduce the transportation
costs substantially.
Permanent gases follow the Gas Equation
oP1 x V1 / T1 = P2 x V2 / T2
oSo, for higher gas content in fixed volume of cylinder, you
need to get higher pressure in cylinder.
For this the cylinders have to be with materials with higher
strength to get higher efficiency.
Everest Kanto Cylinder Limited
P.M.Samvatsar
The
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Effect of Material properties on Gas Cylinders - 1
Gas Volume
Ratio of --------------------------------Cylinder Weight
From the derivation given in the handout it would be clear
that for a given diameter and length of cylinder, the
• Gas Volume is proportional to the pressure
• Cylinder weight is also proportional to the pressure
But
• The cylinder weight depends on wall thickness which is
inversely proportional to cylinder steel strength.
Everest Kanto Cylinder Limited
P.M.Samvatsar
Technical Efficiency of Gas Cylinder
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Conclusion : For a given water capacity and diameter of cylinder,
the ratio of gas volume / cylinder weight i. e. technical efficiency
remains constant and shall only be affected by material
properties and density.
So, to improve the technical efficiency of cylinders high strength
steels have to be employed, with their limitation of intolerance
for embrittling gases and stress corrosion cracking.
Everest Kanto Cylinder Limited
P.M.Samvatsar
Effect of Material properties on Gas Cylinders – 2
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Moving to Higher Pressures - 1
have come as a result of constant human
desire to do things in a better way.
As far as gas cylinders are concerned it meant filling more
gas in a cylinder.
Since the gases follow the Gas Equation, it means the
cylinder has to be filled at increasingly higher pressures. This
gives rise to two challenges
oDeveloping suitable gas cylinders to work at these higher pressures.
oDeveloping infrastructure of gas filling stations who are equipped to
fill gas at these pressures.
The development has been slow due to interdependence of
the above two challenges
Everest Kanto Cylinder Limited
P.M.Samvatsar
Advancements
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Moving to Higher Pressures -2
in related fields is another driver for
technology development. Aerospace imposed more exacting
specifications for weight per unit volume of gas.
Another
important driver is the Oil Crisis in 1970. Rising fuel
Moving to Higher Pressures
costs required lighter cylinders with higher technical efficiency
i.e. Free Volume of Gas / Weight of Cylinder.
Everest Kanto Cylinder Limited
P.M.Samvatsar
Advancement
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Cylinder Evolution- 1
designs mainly depend on the
capability of manufacturing of the Seamless Steel Tubes. The
minimum thickness which could be produced. Secondly they
depend on the development of suitable steels. The evolution was
as below:
Material of Cylinder
Working pr
Heat Treatment
Year
oCarbon Steel:
70 to100 Bar Normalized
1910
oCarbon Mn Steel:
100 to 150 Bar Normalized/QT 1935-60
oChrome Moly Steel:150 to 200 Bar
QT
1960
oChrome Moly Steel: 200 to 300 Bar
QT
1990
oHigh Strength Steel: 200 to 300 Bar QT
1985
oHigh Strength Steel 300 to 400 Bar
QT
1985
Everest Kanto Cylinder Limited
P.M.Samvatsar
Cylinder
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Cylinder Evolution- 2
treatment choice depends on the minimum thickness
available and working pressure required.
Even now, normalized cylinders are popular in small sizes
because hot rolled tubes of lower thickness are not available
and for the thickness, normalized steel can sustain the
pressures particularly for Co2. It makes cylinder more
economical too.
Maneuverability is a consideration which drives the move to
higher strength steels and / or different heat treatment.
50 ltr 300 Bar cylinder with standard CrMo steel would
weight 95 kg against 67 kg of high strength steels.
At present the Indian standards for cylinders cover maximum
tensile strength only upto 1100 MPa.
Everest Kanto Cylinder Limited
P.M.Samvatsar
Heat
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Everest Kanto Cylinder Limited
P.M.Samvatsar
High Strength Steels – Considerations- 1
The
300 bar cylinders were introduced in 1980s, they have
become popular for certain applications because.
“Non-Embrittling” gases like Air, Nitrogen, Argon, Helium etc.
o May need a VIPR – Valves with integrated pressure regulators to
reduce pressure to 200 bar so that no change of equipment is
necessary for downstream equipment.
o They are already meeting additional tests to ascertain behaviour with
flaw e.g. Flawed fatigue and burst test due to almost 50% higher
stored energy leading to higher hazard level. They offer the same
safety level as that of lower pressure cylinders in use.
oWhile choosing the application the user has to understand that
higher tensile and yield strengths affect the following adversely
Toughness
Fatigue resistance
Ductility
Corrosion resistance
Stress Corrosion Cracking
Everest Kanto Cylinder Limited
P.M.Samvatsar
oThey could be used for majority of the gases which are classified as
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High Strength Steels – Considerations- 2
meet these demands on steel they have to be
oRefined – ESR and Re-melted steels
oAddition of certain alloying elements
oClose range of tolerances for each element in chemistry
Should have:
oVery low gas content
oVery low Sulphur, Phosphorus, and Tin Content.
oFine grain
oVery low inclusion rating
Should be processed and tested with
oClosely controlled heat treatment cycles
oUltrasonic flaw detection and other NDT techniques
Everest Kanto Cylinder Limited
P.M.Samvatsar
To
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High Strength Steels – Considerations- 3
manufacturer and the user has to take special care of
the cylinder as the wall thickness is reduced with respect to
the pressure and the margins are reduced so the tolerable
flaw sizes also need to be limited to avoid accidents.
Everest Kanto Cylinder Limited
P.M.Samvatsar
The
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Composite Cylinders
the limitations of embrittling gases and weight
issues normally what comes to mind is the option of using
composite cylinders type 2, 3 and 4.
oType 1:
oType 2:
oType3:
oType 4:
However
All Steel
Metal Liner with Hoop Wound Fiber Wrap
Metal Liner with Fully Wound Fiber Wrap
Non Metal Liner with Fully Wound Fiber Wrap
Composite Cylinders is not a panacea. They have
limitations
Higher cost,
Careful handling or mounting
Gas permeability
Therefore they are not popular even though they are easily
available.
Everest Kanto Cylinder Limited
P.M.Samvatsar
Considering
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Bulk Transportation of Gases
a safer and economical transportation of larger quantity
of gases the cylinder bundles and cascades have emerged.
The cylinder assemblies are grouped as
oCylinder bundles – portable or floor mounted
oJumbo skids
The
user always desires the least number of probable leak
points to have utmost reliability. This could be achieved by
using individual cylinder of large capacity e.g. The jumbo tubes
which could have individual water capacity of 3000 ltr. Most
popular is 2200 ltr 200/250 bar.
Everest Kanto Cylinder Limited
P.M.Samvatsar
For
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Everest Kanto Cylinder Limited
P.M.Samvatsar
Bulk Transportation of Gases
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EKC TUBE TRAILER
Everest Kanto Cylinder Limited
P.M.Samvatsar
Bulk Transportation of Gases
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JOURNEY OF DEVELOPMENT
We
have come a long way in means used for gas storage
Bladders
Hammered and riveted vessels
Carbon steel seamless cylinders
Chromium Molybdenum steel seamless cylinders
High strength steel seamless cylinders
Composite cylinders
Who
comes out as a trustworthy workhorse is of course is the
STEEL CYLINDER
Everest Kanto Cylinder Limited
P.M.Samvatsar
Animal
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Techno Economic Considerations -1
Total Gas
No. of
Water
Gas Cylinder
Transported % Extra Gas Technical
Pressure
Cyls in
Capacity
Capacity Weight
in 16T truck Carried vis-a- Efficiency
(Bar)
16T
(Litre)
(m3)
(kg)
(m3)
vis 150 Bar
m3/kg
truck
1
2
3
4
5
6
7
8
46.7
150
7.00
52
308
2156
-
0.135
46.7
200
9.34
54
296
2767
28.3
0.173
50.0
200
10.0
57
280
2880
29.87
0.175
50.0
300
15.0
78
205
3075
42
0.192
Everest Kanto Cylinder Limited
P.M.Samvatsar
Gas Carrying Comparison Chart
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Techno Economic Considerations -2
Water
Capacity
(Litre)
Pressure
Bar
Gas
Investment
Capacity
per cyl (Rs)
(m3)
1
2
3
46.7
46.7
50.0
50.0
150
200
200
300
7.00
9.34
10.0
15.0
Investment /
m3of Gas (Rs)
% Advantage
4
5
6
6000
7000
7500
10000
857
749
750
667
12.5
12.5
22.2
Everest Kanto Cylinder Limited
P.M.Samvatsar
Investment Cost Comparison with 46.7 Litres – 150 Bar Cylinders
With various Cylinders Pressure Ratings
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Cylinder Bundles / Quads / Cascades - 1
two or more cylinders are held together in a frame
and are also interconnected and connected to the outlet
through manifold piping they are called Bundles, Quads,
Cascades, Skids. They offer following advantages.
 No labour is required for loading and unloading.
Cylinder valve or cylinder will not get damaged
Cylinder tracking/accounting will be easy and cylinders
will not be lost
Cylinders can be easily identified for next test due date.
Everest Kanto Cylinder Limited
P.M.Samvatsar
When
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Cylinder Bundles / Quads / Cascades - 2
Ltr 200 Bar Cylinders are very economical as
compared to 46.7 Ltr 150 Bar cylinders. We get 10 m3 gas
as against 7 m3 (based on what gas we fill)
Each bundle contains 12 cylinders so 120 m3 gas. (in
case of 46.7 ltr x 150 bar we get only 84 m3 i.e. 43%
more.
Ease of filling – 12 cylinders with single connection
No frequent cylinder changing by user
Everest Kanto Cylinder Limited
P.M.Samvatsar
50
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Everest Kanto Cylinder Limited
P.M.Samvatsar
Cylinder Bundles/ Quads /
–3
Cascades
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Everest Kanto Cylinder Limited
P.M.Samvatsar
Cylinder Bundles / Quads / Cascades – 3
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Everest Kanto Cylinder Limited
P.M.Samvatsar
Cylinder Bundles/ Quads /
–3
Cascades
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Everest Kanto Cylinder Limited
P.M.Samvatsar
Cylinder Bundles/ Quads /
–3
Cascades
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Everest Kanto Cylinder Limited
P.M.Samvatsar
Cylinder Bundles/ Quads /
–3
Cascades
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Gas Delivery
Everest Kanto Cylinder Limited
P.M.Samvatsar
.
Thanks for making a beginning over 1 ¼ century ago.
Thanks for patient listening.
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