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stress on a sample probe
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

2009-09-16, 10:39 AM	#1
huangyhg 超级版主注册日期: 04-03 帖子: 18592 精华: 36 现金: 249466 标准币资产: 1080358888 标准币	stress on a sample probe stress on a sample probe 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 __________________ 借用达朗贝尔的名言：前进吧，你会得到信心! [url="http://www.dimcax.com"]几何尺寸与公差标准[/url]