RackleyJ
Mechanical
- Aug 31, 2010
- 5
Can someone give me a guideline, or some reference material that details the differences between the different grades of A514 (specifically Grades B, C and E)?
We typically use A514 Grade B for temperatures up to 700°F. We typically use A514 Grade E for temperatures above 700°F. I have no idea where this criteria came from, and I can't find any performance data comparing one grade to another (other than the chemical makeup).
I have a certain project where a centrifugal fan is built from A514 Grade C, and the temperature is at 968°F (520°C). The impeller is made from 3/4" thick material and from 1/2" thick material. They've been having problems with this fan for some time, and have asked us to suggest design changes. The stress levels appear to be very low (less than 30,000 psi).
My problem is that grade E is hard to get below 3” thick, and grade C is hard to get period. We normally would make this wheel out of grade E material due to the temperature, but I am afraid to suggest it because I honestly don't know if it is more appropriate or not.
I was hoping someone here could provide some more information, or could at least suggest some reference material. Would changing the grade from C to E make a big difference? Does A514 E actually handle higher temperatures better than A514 B (how so)? Any information that could lead me in the right direction would greatly be appreciated.
We typically use A514 Grade B for temperatures up to 700°F. We typically use A514 Grade E for temperatures above 700°F. I have no idea where this criteria came from, and I can't find any performance data comparing one grade to another (other than the chemical makeup).
I have a certain project where a centrifugal fan is built from A514 Grade C, and the temperature is at 968°F (520°C). The impeller is made from 3/4" thick material and from 1/2" thick material. They've been having problems with this fan for some time, and have asked us to suggest design changes. The stress levels appear to be very low (less than 30,000 psi).
My problem is that grade E is hard to get below 3” thick, and grade C is hard to get period. We normally would make this wheel out of grade E material due to the temperature, but I am afraid to suggest it because I honestly don't know if it is more appropriate or not.
I was hoping someone here could provide some more information, or could at least suggest some reference material. Would changing the grade from C to E make a big difference? Does A514 E actually handle higher temperatures better than A514 B (how so)? Any information that could lead me in the right direction would greatly be appreciated.