Recent content by brubakerj

I'm working through the ASME B31G Calculations for the following http://www.novanumeric.com/samples.php?CalcName=B31G I'm noticing for the folias factor <= 20 ASME B31G, 2009, original method Sf=sflow((1-2/3(d/t))/(1-(2/3)*(d/t)/M) so when d=t, i.e. the flaw depth is 100% and there is no...

All, I've been trying to implement the ASME B31G calculations at http://www.novanumeric.com/samples.php?CalcName=B31G Any feedback? I'm trying to understand some of the background. Is Sflow more or less the yield stress and Sf the failure stress for the pipe? -Jeff

UbaidUllah65, Are the numbers matching? -Jeff

The linear doesn't seem to match the example problem. (2.36E-04 versus 3.0e-4). Looking at the graph I wonder if a quadratic scheme would work better. I wish they would give the derivation for these curves, that may give some insight into the best interpretation scheme. These codes so often...

UbaidUllah65, I'm working through the procedures myself at the moment. I curvefit every given curve and evaluated at a given L/2a and r/t. I am interpolating on a_r and debating which interpolation method to use. Is it better to use linear or to use quadratic interpolation? -Jeff

I'm looking at these curves now. It doesn't look like there is enough data. There is just two L/2a curves? I think the way to do this is the following do a linear curve fit for every curve. Calculate all the curves at the given R/t Then interpolate using L/2a and a/r to get an appropriate value.

Consider the poppet weight divided by the area of the orifice. Crane's Tech Paper 410 has some formulas for minimum flow (not sure how they are derived).

UbaidUllah65, Where are the source curve located? Is it a solution to an equation or are the curves available? -Jeff

API 653 (I pasted API 650 twice above) Min Plate for 60.0, 0.1 Calculating Thickness Per 1FT Method on Course1 Course1 D:60.0 G:1.5 S:24900.0 E:1.0 Cas:0.0 currentHeight:32.0 2.6xDx(H-1)xG/(SxE)+Cas=0.291325301205 Min Plate for 60.0, 0.1 Calculating Thickness Per 1FT Method on Course2 Course2...

I matched his numbers in my calculator for course 2. API 650 Calculating Thickness Per 1FT Method on Course1 Course1 D:60.0 G:1.5 S:23200.0 E:1.0 Cas:0.0 currentHeight:32.0 2.6xDx(H-1)xG/(SxE)+Cas=0.312672413793 Min Plate for 60.0, 0.25 Calculating Thickness Per 1FT Method on Course2 Course2...

I've never liked the ASME rules for external pressure. Are you allowed to do FEA under Section VIII-I to find buckling pressure?

PSlem, Send me the spreadsheet if you'd like, I can take a look at it.

Ron, Thanks for the reply. My masters is in Engineering Mechanics, which was through the civil engineering department while my undergraduate coursework and any job experience has been Mechanical. I always assumed strength calculations (like Wind, beam sizing, integrity calculation etc), to be...

I am a feelance structural engineer. I put a few samples of calculations on my website at http://www.novanumeric.com/samples.php and was looking for direction. What types of codes/calculations should I target? Ultimately, I'd like to sell it as a service to develop these calcs for certain...

I think the solver in Excel uses a variant of the Bisection Method http://en.wikipedia.org/wiki/Bisection_method