8/12/2019 Mw Thic Ness
1/5
diameter min wall
thicness
m mm
---------------------------------
Data by Coulson - Richardson1 5
2 7
2.5 9
3 10
3.5 12
1 7
2 9
2.5 10
3 12------------- -------------------
Min welding thickness
Data by Art Montemayor
1 6.4
2 6.4
2.5 6.4
3 6.4
3.5 6.4
1 9.5
2 9.5
2.5 9.53 9.5 Corrosion allowance = 2 mm in the data by Coulson -
Richardson
3.5 9.5 "average" to fil all Coulson - Richardson's data
(R2=0.825)
1 4.8
2 4.8
2.5 4.8
3 4.8
3.5 4.8
built tank (Art Montemayor)
3.05 9.5
5
7
9
10
12
7
9
10
12
2
4
6
8
10
12
14
0 1 2 3 4
sidewall
thickness,mm
vessel diameter, m
Min wall thickness versus vessel diameter
Coulson - Richard
Min recommendedthickness for weldiMontemayor
Welding almostimpossibleMontemayor
Reference of a builMontemayor
8/12/2019 Mw Thic Ness
5/5
diameter min wall Design pressure* corresponding to referred
wall thicknessthicness Vessel diameter cylinder thickness w/o CA
design pressure * (1)
m mm m mm Barg
Data by Coulson - Richardson
1 5 1 3 8.1
2 7 2 5 6.8
2.5 9 2.5 7 7.6
3 10 3 8 7.2
3.5 12 3.5 10 7.7
average of above 7.5
minimum of above 6.8
1 7 1 5 13.5
2 9 2 7 9.52.5 10 2.5 8 8.6
3 12 3 10 9.0
average of the above 10.1
Note:Carbon steel, assumed allowable stress 135 N/mm2
* Including any hydrostatic pressure in addition.
Note:Old information (vague and not verified) suggested that
drum design pressure* lower than about 5Barg
does no longer affect wall thickness, more or less covered by
the thickness needed for the vessel to withstand
its own weight. This roughly complies with above, to a rather
fair degree. Advice is welcomed on the point.
For instance the surge drum of a steam boiler deaerator can be
in this category. Increase of such vessel design
pressure to e.g. 5 Barg cannot be without proper testing
(weldings or other vessel components can be "weaker").
Note:Thickness of vessel heads is not considered above, although
2:1 elipsoidal heads have practically samethickness as the vessel
cylinder for a given design pressure.
Note: CA = corrosion allowance (substracted from wall thickness
before estimating vessel design pressure*).
Note (1): Coulson - Richardson, Chemical Engineering Vol 6
(Design), Chapter 13 - Mechanical design of process
equipment / Membrane stresses in shells of revolution. Hoop
stress=des press*dia/(2*thickness). This formula
is simplified, welded joint factor=1. Head thickness is not
considered, but 2:1 elipsoidal heads would result in
practically same thickness as the cylindrical wall for a given
design pressure*.
5.0
6.0
7.0
8.0
9.0
1 1.5 2 2.5 3 3.5designpressure*,Barg
vessel diameter, m
