Defense questions
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This post was last edited by HSLJHZ on 2015-7-16 at 10:44. Defense questions for the first Kunming class in 2015: 1. Stress control at the large and small ends of a conical head? 1. What are the principles for setting up three saddles on a horizontal container? 2. What is the difference in calculation using oval gaskets and octagonal gasket flanges? What are the resilience indicators? 3. Briefly describe the process of conical shell design and the considerations to be taken into account. 4. Briefly describe the stress analysis of heat exchanger tube sheets and the design calculation process for them. 5. Briefly describe the design process and calculation steps for jacketed vessels.
Kunming class? Luxurious and upscale. For version H, wouldn’t it be more appropriate to move it to the heat exchanger section?
Let’s pick two problems related to the design calculations of conical heads and address them as a way to stimulate further discussion: 1. How to control the stresses at the large end and the small end of a conical head? Major-end controls bending stress + film stress, up to 3 times the allowable value ； The minor end controls the film stress; a value of 1.1 times the allowable value is acceptable. 3. Briefly describe the process of conical shell design and the considerations that need to be taken into account. (The following all relates to the calculation of conical heads under internal pressure.) First, check a table using the half-cone angle to determine whether edge folding is required. If there is no folding: 1. Calculation of the wall thickness of the conical shell body: calculated using the second radius of curvature at the larger end ； 2. Strengthening calculation for the larger end: Check the diagrams to determine whether strengthening is necessary; if so, calculate the wall thickness required for the cylinder at the larger end, and then refer to the diagrams again to determine the strengthening factor ； 3. Strengthening calculation for the small end: Check the diagrams to determine whether strengthening is necessary; if so, calculate the wall thickness required for the small-end cylinder, and then refer to the diagrams to find the strengthening coefficient. If there is a fold: the larger end is calculated as a butterfly head, while the smaller end is calculated in the same way as without a fold. Finally, the stability at the junction of the large and small ends with the cylinder shell should also be calculated (circumferential instability caused by discontinuous stress). In the calculation of the reinforcement sections, it is important to ensure that the lengths of the big-end and small-end reinforcement sections meet the required specifications. Please correct me.
4. Briefly describe the stress analysis of heat exchanger tube sheets and the design calculation process for them. Back in school, I could answer some questions on this topic; now, I don’t even know how to calculate the number of tower plates. :L