Size of embedded sleeve
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When perforating the dike of the acetic acid storage tank, what size should be chosen for the embedded sleeves with a DN300 diameter and a insulation thickness of 70? Also, what sizes should be selected for the embedded sleeves with a DN250 diameter and an insulation thickness of 70, and those with a DN100 diameter and an insulation thickness of 60?
Looking forward to the answer! I have the same problem!
We generally choose DN300 sleeves and DN500 seamless pipes, while for DN250 we opt for DN400 or DN450 seamless pipes. If welded coiled pipes are used, the inner diameter of the pipe should be more than 30 mm greater than the sum of the pipe diameter and the total insulation diameter
It is recommended not to use insulation when making the perforation, as insulation makes it impossible to seal properly; choosing a pipe diameter that is one or two sizes larger than what you will use is sufficient
I agree with the person above; it’s better not to use insulation inside the pipes when there are sleeves outside. Insulation in underground pipes makes it easy for water to get in, and once water gets in, it’s difficult to remove, which accelerates the corrosion of the pipes. Our usual approach is to choose a pipe that is one or two sizes larger than the diameter of the tube in question, seal the casing at a height of about 100 mm above the ground surface, and then drill a small hole of around 10 mm in the casing.
Reply to ero229: Is the height of the piercing around one meter above the ground?
If it is at a height of over one meter above the ground and there is no risk of exposure to rainwater, then heat retention is possible; in that case, the diameter of the pipe sleeve should be larger than that required when heat retention is needed. If a DN300 pipe with 70 units of heat retention is used, then choosing a DN500 pipe will suffice.
Reply to 7# zero229: Thanks! {:1_90:}
The sleeve size can be two sizes larger than the original pipe diameter. If there is air inside the sleeve, no insulation treatment is necessary, but both ends of the sleeve must be sealed as required.
Study Page 74 of Volume 2 of the Chemical Pipeline Manual carefully; don’t talk nonsense