Inspection issues for imported pressure vessels
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My company has installed several imported pressure vessels, which are purifiers for gases such as nitrogen, oxygen, argon, and hydrogen produced in Japan. The inner tube is made of stainless steel; the middle layer contains an insulating layer, heating wires, heat transfer oil, and special high-temperature resistant cement. The outer layer is a stainless steel casing that can be removed. The operating temperature ranges from 500°C ± 5°C, and the internal volume is between 35 and 600 liters. At present, after three years of use, a comprehensive inspection is required. Our local special inspection agency has required that the equipment be shut down so that the insulation layer can be removed and the wall thickness as well as the welds can be inspected. When we consulted the manufacturer, they stated that once the intermediate insulation layer is removed, the equipment becomes unusable, and it would be necessary to reinstall the insulation layer, heating wires, heat transfer oil, and special high-temperature resistant cement (an approach that involves high risks and high costs). They do not recommend removing the insulation layer, but they also did not provide any other viable inspection methods. The company keeps pressing me to handle this issue, and after searching extensively, I have been unable to find any appropriate literature or inspection techniques. I am posting this request here in hopes of getting some suggestions and solutions; I would be extremely grateful! :handshake
It is best to communicate with the inspector; at the outer side corresponding to the inner wall weld, use a cutting angle grinder to create an opening. After inspection, cover that area with galvanized iron sheet larger than the damaged section, apply silicone sealant for waterproofing, and then secure it in place with self-tapping screws. For thickness measurement, use a triangular scraper to create a triangular cut in the insulation layer, push the glass wool inside aside, and remove the anti-corrosion coating with the scraper before taking the measurement. The key is to coordinate feasibility. (For reference)
What the fuck for a check? How can one conduct destructive testing on equipment? ! Complete nonsense. If the ball has the capability, let him go and disassemble those missiles, the DF41 and things like that for inspection; they’re corrosive, after all, and they don’t target good people. .
Throw it away and get a new one; say goodbye to it. You tell him to go check the Japanese people. . . . . . It’s strange if he doesn’t run away in terror.
We do indeed want to remove part of the insulation to inspect the welds and wall thickness, but the manufacturer stated that partial damage followed by partial restoration could lead to unstable operation of the equipment; therefore, removing the insulation is not recommended. Instead, the entire insulation has to be replaced, which is costly in terms of both money and labor, and it also has a significant impact on the company’s continuous production. What I’m asking is whether such pressure vessels can be inspected as non-dismountable vessels with jackets (similar to cryogenic storage tanks)?
Indeed, the manufacturers are also puzzled – with so many sets of equipment sold, it’s only our company that needs to damage the insulation in order to conduct inspections; they have never encountered such a situation before! So it’s impossible to provide a testing method; since it’s delivered as a complete unit, removing the insulation for testing is pointless (the manufacturer doesn’t want to say so outright)! :L
This requires funding and connections to get done: lol
This shouldn’t be something said by the equipment manufacturer, right? Isn’t it just insulation? Is it that advanced? Because you don’t even know whether the normal operation of the process will be affected after these thermal insulation issues are resolved? Hehe, it seems the problem lies in your lack of understanding of the equipment.
It’s my first time using this type of equipment and conducting inspections; the management has asked us to give full consideration to the stability of the equipment, as it is used in production lines that are already in mass production, and we cannot afford any accidents (the products are electronic devices). When we encounter problems, we can only turn to the manufacturer for advice, as they have more experience. As you know, Japanese equipment cannot be repaired casually; otherwise, no after-sales service will be provided. There’s no alternative – domestic equipment is not capable of producing gas with high purity on a stable basis. (In fact, the reason we invested heavily in purchasing Japanese products was to ensure stable production, that is, continuous operation 24 hours a day, 365 days a year.) According to preliminary inquiries, the repair cost is 3,000 yuan per hour (there are 14 such devices in total). The conditions for on-site repairs are very limited, and they cannot guarantee that the devices will be in the same condition as when they left the factory after repair.
It’s hard to put into words – I’ve tried many approaches and spent a lot of money. The person in charge of testing here said that since it’s the first time they’re testing this type of equipment, they must follow the rules; they also need to learn* how to do it!
I’ll just say one thing: his filler is a technical asset that can be kept confidential. Regarding the principle of insulation for pressure vessels, I’m speechless. The equipment belongs to you once it’s purchased, but you hand over sovereignty to someone else… I don’t understand it. It’s okay – he plans to insulate it for you from scratch, without asking you to rebuild it; P This is just my personal opinion for reference only.