The confusing issue regarding the segmented treatment of ASME vessel jackets. There are also problems found in the external pressure calculation results

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This post was last edited by lishunnian on 2019-5-6 13:09. Recently, I encountered a rather large container that required a jacket to be designed. Such a problem has arisen. A bit confused. All calculations were carried out in PVELite2018. According to the design code ASME Section 81, if it is designed with an integral bottom head jacket, then three reinforcement strips of 200x40 must be added due to considerations related to external pressure calculations. However, the department head had a sudden idea and asked me to process the jackets in segments, which resulted in 81 sets of Type 4 jackets in Appendix 9. Then, the average segment of 800 can’t be passed, nor can 500. Average segment length is 1700 mm, passed? ! Damn! What’s going on? If it’s too short, it won’t pass; if it’s long enough, it will pass. I’m fascinated. Then I looked at Appendix 9, but it seems to say not much about type 4 jackets; the main information is in the earlier sections. I wanted to ask, will this work? Can this calculation sheet be produced? I’m not sure what to think. Damn it:funk: Please give me some moral support, big bro. Container parameters: inner diameter 4500, tangent distance 6900, wall thickness 24; material SA516-70. Inner diameter of the jacket: 4650, wall thickness 20; thickness of the end cover: 25, material SA516-60. Internal pressure: 1.5 MPa, jacket pressure: 0.4 MPa. Temperature: 99. Corrosion allowance: 1.5. Note: A problem has just been identified. Using the external pressure curve CS-5 with a value of A equal to 0.00331 (which is the value I obtained for the head jacket), it actually gives a B value of 15? ! Damn?! The B value for CS-5 is at least 20. The 2.06 material still has a value of over 140 at 0.003. Is there something wrong with this thing? ! I’m going to call EagleMap to ask. (That company, Eagle Picture, doesn’t even have a technical department – they said they only have sales and front-office staff. What the hell?)