I have a flange I’m looking at and the top half of it is a flat face flange while the bottom half is a ring joint flange (ring depth is 0.3”). The type of gasket the engineer is using is an elastomer with less than 75A shore Durometer with dimensions of: Gasket height=1.0” Gasket thickness=0.5”...
Hypothetically, I have a vertical pressure vessel that is split in half around the circumference in the middle and is connected by two extremely large bolted flanges. There is a manway on one of the halves of the pressure vessel and it is extremely close to the bolted flange, where the limit of...
Hello everyone,
I have a pressure vessel designed to the ASME code and stamped for lethal service (L-stamp) it has been operating for over two decades with no real problems but during a recent shutdown and inspection it was discovered that an inlet/outlet pipe was not attached with a full...
Good morning everyone,
I have two questions. The first is about the ASME BPVC Section VIII Div. 1 code, and the second is about general engineering practice.
First question: In the ASME code a nozzle attached with an internal and external (double-sided) fillet weld, as shown in figure UG-40...
I am hoping the experience on here could point me in the right direction or give me a design formula that I can use to check if the thickness of the skirt is large enough.
I have tried looking in numerous design handbooks and I can only find equations for a skirt that is welded to the straight...
Here’s my situation. I have a relief valve with an inlet opening of ¾” but the line going to it is ½” [I know this configuration isn’t code compliant because of UG-135(b)(1)].
The problem I see with this configuration is, because the area increases at the relief valve inlet, the pressure in the...
Hello all,
I am trying to find a section in ASME BPVC Section VIII Div. 1 that explains how to lower a pressure vessel’s MDMT (without impact testing) when the material is not carbon or low alloy steel. I’ve read UCS-66, UCS-67, UCS-68, Figure UCS-66.1, and Figure UCS-66.2 but all of those...
Hello All,
My question is if you have two small nozzles (let’s just say the finished diameter is 2”) in a pressure vessel with a thin shell thickness (let’s say 0.25”) and they are relatively close together. Do you need do preform a calculation to determine if their centers are further away...
Hello Everyone,
I'm trying to calculate the maximum weight each lug on a pressure vessel can support and I'm a little confused about a variable in the equation I'm using. The equation is from the Pressure Vessel Handbook 10th ed.
The variable for H (Lever arm of load) is slightly confusing for...
I’m evaluating the design of a pressure vessel and it is constructed with an ellipsoidal head that is only 1/16 in thick (in the fully corroded condition). I’ve calculated the value for L (Inside spherical radius) and have come up with 40.63. The ratio of these two numbers (0.0625/40.63 =...
I was reading over the codebook and came across a material (SA-312 TP304L) that has two different allowable stress values. One of them (The higher value) has note G5 attached to it.
G5 says “Use of these stresses may result in dimensional changes due to permanent strain.”
My question is: who...
Paragraph 4.3.10.1 states the requirements for using the equations in Paragraph 4.3.10 to calculate the combined loading and allowable stresses. I understand 4.3.10.1(a) and (b) but I am slightly confused why 4.3.10.1(c) is there.
How does having an inside radius to thickness ratio less than...
I’m working on a saddle support calculation with two identical horizontal pressure vessels, one stacked on the top of the other (The top vessel will have bottom saddles and the bottom vessel will have top saddles, both having flat plates at the contact point. Vessels are then held together by...
I’m working through a ASME BPVC Section VIII Div. 2 recertification for a horizontal pressure vessel and under section 4.3.10 “Combined loading and allowable stresses” there is a formula (Equation 4.3.33) that has variables of: Net-Section Bending Moment, and Net-Section Axial Force. In the...
During a recertification of a saddle support calculation for use in a lethal system the manufacturer identified the contact angle of the saddle supports for an ASME Section VIII Div 1 horizontal vessel was 120°. The contact area included the ½” wear plate that did not extend beyond R/10 inches...
I'm doing a calculation where the contact angle for the pressure angle is 120 deg., but the manufacturer is taking that angle from the tip of the wear plate not the horns of the saddle supports. The actual contact angle the saddle supports make with the vessel is 116 deg.
I was wondering that...
