Pressure Vessel Lug Design
Pressure Vessel Lug Design
(OP)
I am trying to follow the Pressure Vessel Design Manual's (by Dennis R. Moss) proceedure for the design of lug supports. I have run into a units proplem, however. The equation for the uniform load on base plate (w) has the wrong units. In the notation (nomenclature) section, (w) is stated to have units of (lb/in). The equation is
w = Q/(a*l) where (Q) is the vertical load per lug (lb), (a) is the bearing length (in), and (l) is the length of the base plate across the gussets (in). As you can see, the units per the equation are (lb/in2). Is this equation wrong? The rest of the proceedure is incorrect (units wise) as it is currently written. Could anyone please help our with this? Thanks in advance!
Best regards,
Danny
w = Q/(a*l) where (Q) is the vertical load per lug (lb), (a) is the bearing length (in), and (l) is the length of the base plate across the gussets (in). As you can see, the units per the equation are (lb/in2). Is this equation wrong? The rest of the proceedure is incorrect (units wise) as it is currently written. Could anyone please help our with this? Thanks in advance!
Best regards,
Danny





RE: Pressure Vessel Lug Design
use Bednar
Thanks
Murgan
murgan1@hotmail.com
RE: Pressure Vessel Lug Design
I also use to use the book by Moss, but ran into so many mistakes, units problems, and incorrect formulas that I try to stay far away from it.
I would recommend using Henry Bednar's book or the book by Eugene Megyesy (Pressure Vessel Handbook). Both of these are excellent resources to have. Others include books by Kanti K. Mahajan, Lloyd Brownell, and Edwin Young.
I would really recommend not using the book by Moss anymore, unless they have really revamped it and ensured that the mistakes from previous printings have been eliminated.
RE: Pressure Vessel Lug Design
Don’t forget to allow for shock lifting loads and if you are using the lug to manipulate the vessel, tailing lugs, you must appreciate the geometry of the loading as the vessel moves.
If the vessel is heavy or very thin you could distort it, it may be worthwhile doing a local load calc to WRC 107 or BS5500 on the shell.