Let’s discuss “returning to the jurisdiction” again, friends from the sea come in!
Thread Content
A friend of mine posted a discussion thread two days ago.: https://bbs.hcbbs.com/thread-3597657-1-1.html The general content is: There is a piece of equipment that uses a steel pipe with an outer diameter of 159mm and a thickness of 5cm as the cylinder. The volume of the equipment exceeds 0.03m3. Does such equipment require supervisory inspection? Comparing the three provisions of 1.3, it must be met at the same time to be included in the jurisdiction, 159-5 * 2=149, less than 150, so I responded immediately: “unnecessary! ” A question suddenly occurred to me today, and I thought it was a bit interesting. What question should we discuss? When we discussed the Haiyou issue above, we did not ask or consider the issue of corrosion margin. If the corrosion margin of this equipment is 1, does it fall under the jurisdiction of the tolerance? The original words of Rule 1.3(2) of the Solid Capacity Regulation are:: The volume is greater than or equal to 0.03m3 and the inner diameter (non-circular cross-section refers to the maximum geometric size of the inner boundary of the cross-section) is greater than or equal to 150mm. There is some doubt here:: Is this inner diameter the inner diameter obtained by subtracting the nominal thickness from the outer diameter of the pattern, or is it the inner diameter obtained by subtracting the effective thickness from the outer diameter? Let’s go back to the hypothesis just now. If there is a corrosion allowance of 1mm (assuming uniform corrosion) and a design service life of 10 years, then when the equipment is used for 5 years, the actual inner diameter will be 150mm. After 5 years, the diameter will definitely be greater than 150mm. It’s a bit nitpicking, but this is the fact. I still think it needs to be discussed. Personally, I think this kind of marginalia is a bit controversial. Classification supervision should not be excessive. Everyone is welcome to discuss it.
Regarding the question raised by Haiyou, if the corrosion allowance of the equipment is 1, then the inner diameter will gradually increase during use, and may exceed 150mm after 5 years of use. Therefore, the actual inner diameter, which is the inner diameter obtained by subtracting the effective thickness from the outer diameter, should be considered when considering jurisdiction. From this point of view, the diameter of the equipment does not meet the tolerance requirements within its designed service life, so supervisory inspection may be required. However, it should be noted that the actual situation may be more complex, so the specific judgment needs to be comprehensively analyzed based on the actual situation. .
This post was last edited by wanlirn on 2023-5-9 15:35. Of course, it is the nominal diameter and nominal thickness. You have confused quality management and mandatory management.
People are afraid of getting into trouble and cannot focus on just one part of a problem. Your problem doesn't exist at all ； reason: 1. The fact that pipes with a nominal diameter less than 150mm are not within the scope of large-capacity regulation does not mean that they are not within the scope of other regulations. ； 2. The scope delineated by the Special Equipment Law is mainly divided by pressure, volume, medium, and temperature, and it cannot be applied mechanically by just deducting points. Manufacturing units and installation units are very comfortable with these issues, and those who have no objections to Aikou are generally the user units and supervisory departments.
This post was last edited by wanlirn on 2023-5-10 08:27. People are only discussing containers. The poster’s question is not meaningless. In fact, the poster’s question is essentially whether the size among the three conditions is the nominal thickness or the design thickness. I think it is the nominal thickness.
This alone is ridiculous. Even so, he didn't even read the notes and chewed on every word.
If you want to discuss, then discuss. If you don't want to discuss, just stand aside. Come and show off what you are capable of.
You are right. If the diameter is larger than 150, such as DN1000, it is judged without considering the corrosion allowance. Therefore, the inner diameter here should not consider the corrosion allowance.
Do you know what corrosion allowance is? If you don’t know, check out GB/T150-2011. For inner diameter requirements, check out TSG 21-2016. You can ignore the remarks.
If there is a technical discussion, welcome with both hands. If you come to find trouble, go away, don't act like a big-tailed wolf.
https://bbs.hcbbs.com/thread-1950127-1-1.html This is your own sticker. If you can't tell the difference between "design thickness" and "nominal thickness", how can you have the nerve to come here?