Weight Piping Input

Posted by: josephlee

Weight Piping Input - 04/06/10 06:31 AM

Hi,

I have query in weight piping dialog input.
In PVElite at the time of compute weight and area why it does takes 0.7 in account.
where I get the 100% area of the following

can any one suggest this.

Regards,
Joseph
Posted by: Ray_Delaforce

Re: Weight Piping Input - 04/06/10 08:15 AM

Hello Joseph

I am having difficulty in following what you mean. Could you perhaps explain where the 0.7 factor is used in assessing the weight of the pipe. Also, I need to know what you mean by '100% area'. If you could clear up those two things for me, I shall be only too pleased to answer you questions.
Posted by: M.SHUKLA

Re: Weight Piping Input - 04/08/10 10:54 AM

Hello Ray,

I got his point & I would clarify as under:

1) While entering "piping weight" in "weight input", PVElite would take the total weight of the piping attached & also the total area of the pipe (insulated or uninsulated as per your input).

2) Now, consideration of 0.7 (shape factor, Mr Josephlee am I correct?) shall be incorporated after the program has been run & that would be during wind analysis.

For Ex;
Area of Shell=10 mm2
Area of pipe=2 mm2
Total area (before run)= 12 mm2

If shape factor is applied before the program run then total effective area would be = 10 + (2 * 0.7) = 11.4 mm2
&
after program run it would become 11.4 * 0.7 = 7.98 mm2

Hence, reduction in area by 33%.

I think this would have cleared your doubt.
Posted by: Ray_Delaforce

Re: Weight Piping Input - 04/08/10 03:06 PM

Ok Folks

I think I've got your drift. You are talking about wind load and the projected area of the vessel. In the case of the vessel there is shape, factor which is determined by the wind code that is chosen. It may be 0.7, but it may be another value.

In PV Elite, the areas of the nozzles and flange are not added to the projected area of the vessel. You will notice that in the general input screen when you are adding shells and heads, there is a field called: 'Wind Diameter Multiplier'. By default, this is set to 1.2. What this does is to multiply the diameter of the vessel by that factor to artificially increase the actual diameter(s) of the vessel. This multiplier takes care of things that are attached to the vessel, such as nozzle, platforms, and other additional attachments.