CharlieH
Mechanical
- Mar 23, 2005
- 14
I need assistance determining what size (OD, wall thickness, etc) sample probe we can install in a stack that can handle the vibration and force due to gas (density = 0.068 lb/ft^3) velocity.
We have a flue gas stack with inner diameter of 100". The velocity of the flue gas is about 62 feet per second. We would like to install a sample probe that extends to the stack center through a 4" nozzle port. So, the probe will be about 55" considering the distance from the shell to the nozzle flange.
The probe will be fabricated by drilling a 316 SS blind flange, inserting the 316 SS probe through the hole in the flange, full penetration welding the probe to the flange and connecting a coupling for sample gas transport purposes. The preliminary probe dimensions provided to me are as follows:
0.875" OD, 0.515" ID, 50" long (this is the length that actually extends in the stack that is subjected to the flue gas velocity)
I've determined the drag force to be about 152 lbf/ft^2 on the probe. This equates to approx 35 lbf.
Can you please provide your advice on determining whether the probe will handle the loads? I assume I have to consider both the load due to the flue gas as well as the vibration effects on the probe. At this point, I am mainly interested in determining the effects of the drag force, so any formulas or guidance there would be greatly appreciated.
Regards,
Charlie
We have a flue gas stack with inner diameter of 100". The velocity of the flue gas is about 62 feet per second. We would like to install a sample probe that extends to the stack center through a 4" nozzle port. So, the probe will be about 55" considering the distance from the shell to the nozzle flange.
The probe will be fabricated by drilling a 316 SS blind flange, inserting the 316 SS probe through the hole in the flange, full penetration welding the probe to the flange and connecting a coupling for sample gas transport purposes. The preliminary probe dimensions provided to me are as follows:
0.875" OD, 0.515" ID, 50" long (this is the length that actually extends in the stack that is subjected to the flue gas velocity)
I've determined the drag force to be about 152 lbf/ft^2 on the probe. This equates to approx 35 lbf.
Can you please provide your advice on determining whether the probe will handle the loads? I assume I have to consider both the load due to the flue gas as well as the vibration effects on the probe. At this point, I am mainly interested in determining the effects of the drag force, so any formulas or guidance there would be greatly appreciated.
Regards,
Charlie
