Maximum Value Of Bending in Columns
Maximum Value Of Bending in Columns
(OP)
Hello,
To design of pressure vessels under ASME Sect. VIII, what is de maximum value of tolerance for bending (deflection) in vertical columns. By some document I found 6inch/100ft; That is true?
Thanks.
To design of pressure vessels under ASME Sect. VIII, what is de maximum value of tolerance for bending (deflection) in vertical columns. By some document I found 6inch/100ft; That is true?
Thanks.





RE: Maximum Value Of Bending in Columns
Narendra K. Roy
Gramya Research Analysis Institute,
PO box 4016, Vadodara 390015, India
Website: www.gramya.com ; www.charismaglobal.com
RE: Maximum Value Of Bending in Columns
Column deflection is mainly limited in order to ensure that the internals - (trays, distributor trays in packed columns, etc) funtion correctly and there is no bypassing between the gas going up the column and the liquid coming down it.
RE: Maximum Value Of Bending in Columns
Also check your foundation for the suitablity for the deflection condition.
The maximum static deflection allowed is generally L/200 when the vessel is subject to the design wind load. Where L is the height of the column. This is applicable for columns for L/D in excess of 10 or if the column is more than 30m High.
The above is the spec of Dupont. As far as UOP or EIL is concerned the allowable deflection is almost the same.
RE: Maximum Value Of Bending in Columns
further to all of the above, don't forget about wind induced vibration if the thing is very tall and slender.
Sometimes this may be the criteria which will determine the thickneses of shell strakes - especially the ones at the bottom.
John