API 676 External Loads

[Greg1920]

I am doing preliminary stress work on some PD pumps which will be purchased at a later date. At this point the vendor is not determined. They will be purchased to API 676. In looking at API 676 there are nozzle loads provided but I can not make any sense out of them. They are as follows

2.4 External Forces and Moments
For pumps with steel or alloy-steel casings, inlet and outlet
nonles shall be capable of withstanding forces and moments
from external piping determined by the following
formulas (see Figure I):
F, = 13D Mx = 7D
F = 13D M = 7D
F, = 13D M, = 7D
or in conventional units
F, = 75D Mx = 125D
F = 75D My = 125D
F, = 75D M, = 125D
Y
Where:
D = nominal pipe size of the pump nozzle connection in
millimeters (inches).
F, = force in Newtons (pounds) on the x-axis, which is
parallel to the shaft axis.
F = horizontal force in Newtons (pounds) on the y-axis,
which is mutually perpendicular to the x- and z-axis.
F, = vertical force in Newtons (pounds) on the z-axis,
which is mutually perpendicular to the y- and x-axes.
Mx = moments around the x-axis. in Newton-meters
(pound-feet).
M - moments around the y-axis, in Newton-meters
(pound-feet).
M, = moments around the z-axis, in Newton-meters

Base on the units given this does not make sense 1 lb = 4.4N and 1 ftlb = 1.35 Nm so based on the above formulas the nozzle loads would be different depending on what units I use.

Does anyone have any experience in working with this standard that can explain how the allowable nozzle loads are properly calculated?

 

[Greg1920]

Nevermind I am an idiot. It all works out.

I was multiplying 13*8 for 8 inch pipe instead of 13*200

 

[BigInch]

D N Nm
400 13 5200 5 2000

lbs Nm
16 75 1200 125 2000


**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[BigInch]

Whoops too late.

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/