Recent content by SD12

Hello. I am trying to figure out what is the realstic value for the tolerance zone that can be obtained for the welded structure of this type. To me, even Ø0.1 looks challenging to get.

Yes. But my question is about that Ø0.01 tolerance value. Is this value realistic for a welded structure? This part isn't made by machining.

Hello. Would you please advice me about the admissible tolerance that controlls coaxiality of two cylinders welded to the steel plate. See the picture attached.

I actually haven't seen this sentence. I have the standard issue from 2015. Thank you. Are there any worked examples for chapters 17 and 18?

Hello! I have made a calculation of the number of equivalent full pressure cycles and my result is far more than 500 cycles. What is the procedure then? Should I take the number of equivalent full pressure cycles and compare it to FAT 100 S-N curve? Or it is more complicated than that? Do we...

@CuMo, I do agree with the safety concerns. But if there is a metal to metal flange, the assembly condition loads makes no sense. There is no way, in my opinion, for flange to fail. I am talking specifically about this eqaution: W=0.5*(Amin + A)*f (look at attached picture). Then this load is...

Thank you for information. I have written some questions but by some reason my reply went to the admins for some kind of controll - strange. If my reply isn't here by tomorrow, I will write it down one more time. Sergey

Hello! I have a question: What is the purpose of the moment for assembly conditions? To calculate stresses and thickness of a flange we are using moments for operating conditions. Moment for assembly conditions just adds confusion during calculation and is urealistic huge compared to operation...

Yes, it probably will. But to asses the stresses in knuckles between the segments is the issue.

Hello. No, I do not use the ASME code. EN 13445-3 is preferable but it has no stress assesment procedure as far as I know.

Hello! I am trying to figure out how to perform a structural analysis of the rectangular draft tube to a Francis turbine subjected to internal pressure. I would like to know if there are any rules or codes or theory books that gives an introduction to this problem. There are two issues: -...

Hello. I try to understand the following equation: Kv = Q / sqrt(delta p), whre "Kv" is in m^3/s, "Q" is in m^3/s and "delta p" is in MPa (or bar). If we divide flow (m^3/s) by the square root of pressure difference (MPa), how do we get the value of Kv to be in m^3/s? Please, give me an...

honza1801 Thank you for reply and comprehensive explanation. Best regards, Sergey

Hello. I am interested in design of the ball and butterfly valves that used in hydropower industry. Such valves installed in front of the turbines in hydropower plants. Which standards and/or literature describes the following: Stress analysis of the valve housing, counterweight design and...

Hello. I am interested in design of the ball and butterfly valves that used in hydropower industry. Such valves installed in front of the turbines in hydropower plants. Which standards and/or literature describes the following: Stress analysis of the valve housing, counterweight design and...