【JST-063】One-on-one consultation office for container technology experts

This post was last edited by yuchenchf on 2012-4-4 08:59. It’s quite quiet here; I’ll ask a question. I want to know: (1) For half-pressure containers, we emphasize rigidity and stability – but how exactly do we calculate rigidity and stability? (2) Half of the atmospheric-pressure vessels are covered by those basic standards: one is NB/T47003.1-2009 and the other is GB50341 – just these two standards. The wall thickness is calculated using the formulas in these two standards, but I can’t even believe the numbers that result from such calculations May I ask, how is it generally calculated? (3) Many ordinary vertical tank containers are quite small, and they don’t require a bottom plate as specified in GB50341; usually, it is just a circular plate. So how should the thickness of this circular plate be determined? (4) For ordinary small vertical tank vessels (D≤5000 MM), a flat cover is used as the head, and angle steel is employed as reinforcing members (for example, four pieces of angle steel arranged in a cross shape). How is the size of this angle steel determined? (The standards are rather vague.) (5) Small vertical tankers (D≤5000 MM), with an agitator added on top; I plan to use channel steel to create a support structure on the flat top – what should be the model of the channel steel? Actually, what I most want to learn are the specific steps for performing mechanical calculations. I wasted time on this before; I’ve asked questions like these before as well, but whenever I got a substantive answer, I would doubt whether it was because my question wasn’t phrased clearly enough Or...... (Moderator’s note: Refer to answer on floor 3)

The last edit to this post was made by jia717 on 2012-3-14 at 09:20. (1) We haven’t calculated the stiffness of the pressure vessel itself, such as that of the cylinder or the head. I recall that GB150 version 89 specified a requirement of 0.2% of the diameter for the thickness of the cylinder walls; this was said to be for reasons related to stiffness. As for the stiffness in other areas, such as that of the cylinder at the saddle, it can be calculated to determine; of course, factors such as the material and other loads must also be taken into account. Of course, some tube sections have relatively thin wall thicknesses; to prevent deformation during manufacturing, the process generally requires the use of additional fixtures. (2) Why don’t you believe it? Is the calculated wall thickness too small? The pressure in a vessel at atmospheric pressure is already low, so the calculated thickness is naturally very small. (3) The calculation of the bottom plate thickness was previously done using API; it’s been so long that I’ve forgotten it. (4) For the specifications of angle steel, it is recommended to refer to Table 6-5 in NB/T47003.1. (5) We haven’t carried out any specific calculations for this situation either. I think it mainly involves a mechanical verification of the channel steel – first select a model and then conduct the verification on it. What was said above is not necessarily correct; it is for reference only. Please feel free to point out any errors: lol

This post was last edited by yuchenchf on 2012-4-4 09:00. Regarding the inspection of pressure vessels: major repairs are needed, and liquefied gas storage tanks require inspection; to access the equipment, how is the liquefied gas inside the tanks removed? (The site does not allow queuing); can it be completely purged using nitrogen alone? (Publisher’s note: Refer to answer on floor 5 for reference)

We encounter this situation relatively rarely, as we are a container manufacturing company. Personally, I think it should be possible to replace it with nitrogen in theory, but to what extent the replacement should take place is indeed a question. :handshake

This post was last edited by yuchenchf on 2012-4-4 09:00. Request for help: When calculating the negative pressure of tower equipment, if there are multiple reinforcement rings, the calculation lengths between each ring are not all the same. In such cases, only one value can be entered for each section of the tower. Should one choose the largest calculation length to enter (the same applies to half the sum of adjacent lengths)? If the calculations are valid, then those with smaller spacing values should also be valid, right? That’s how I think about it, but I’m not entirely sure, so I’m seeking advice here. (Publisher’s note: Refer to answer on floor 9 for reference)

I have a question: how often should the gas storage tank be inspected? Including the frequency of recording pressure gauge indication data?

Where can I find the isothermal adsorption curves for molecular sieves? Thank you!

This post was last edited by jia717 on 2012-3-30 at 20:37. Request for help: When calculating the negative pressure of tower equipment, if there are multiple reinforcement rings, the calculation lengths between each ring are not all the same. In such cases, only one value can be entered for each section of the tower. Should one choose the largest calculation length to enter (the same applies to half the sum of adjacent lengths)? If the calculations are valid, then those with smaller spacing values should also be valid, right? That’s how I think about it, but I’m not entirely sure, so I’m seeking advice here. When there are multiple reinforcement rings, the calculation length is of course the longest distance between them; a longer one will meet the stability requirements, and a shorter one can also meet them, provided that the tube sections have the same diameter, wall thickness, and material.

This post was last edited by yuchenchf on 2012-4-4 09:01. I need help regarding a storage tank at atmospheric pressure: its diameter is approximately 3000 mm, and the wall thickness is about 8 mm. A spherical head is planned to be installed at the top of the tank. I want to know how to connect this head to the tank body. The customer requires that the upper surface after connection be smooth. What troubles me now is how to hide the groove that forms as a result of embedding and welding the spherical head The customer is in the food industry and has relatively strict requirements regarding appearance. (Moderator’s note: Refer to answer from floor 12 for guidance.)

Hello! What are the typical height requirements for the distributor and the cold hydrogen tray in a hydrogenation reactor? My hydrogenation reactor has an inner diameter of 2400 mm, with two catalyst beds; each catalyst bed is 6 meters in height.