Regarding the lifting method for vertical heat exchangers without lugs
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Regarding the lifting scheme for vertical heat exchangers without lifting lugs, since the design institute did not provide any lifting lugs for maintenance purposes, steel ropes are used for lifting during maintenance. During this process, the vertical heat exchanger is turned from a vertical position to a horizontal one; in this process, the two steel ropes tend to slide at the head section, and such sliding poses a serious risk during lifting. Therefore, I would like to discuss with experts how to avoid this sliding and what measures can be taken.
The problems mentioned by the moderator rarely occur; generally, equipment is equipped with lifting lugs. There are also very few cases where it is not used, and here are a few suggestions: 1. Tie it directly. It is recommended to use slings, as they have a slightly larger contact area than steel cables, resulting in greater friction. Ordinary riggers can make latches. 2. For end caps with flanges in the middle, it is possible to fabricate matching flanges and weld lifting lugs; of course, the thickness and stability of the end cap must be taken into consideration. 3. Doing the inverted pole hold is a bit more strenuous. 4. Vertical heat exchangers generally have an operating platform; lifting lugs can also be welded to the pads provided on the platform, and these lugs are removed after lifting is complete. That’s all I can think of for now; I’m not sure if it will be useful to you ;P
There are no lifting lugs, but there must be mounting brackets anyway; otherwise, how could the heat exchanger stay suspended in the air? Wouldn’t it be possible to lift it using those brackets?
It is recommended to use the previous image, as it is easier for discussion.
My heat exchanger tends to get clogged; the medium and its own weight amount to around 17 tons, so using slings might not be very safe； On site, we use binding at the flange position of the upper head; it’s fine to lift it in an upright position. However, when changing it from an upright to a horizontal position, the two binding steel ropes and clamps tend to slip, which makes the lifting process unsafe. I’m wondering what the structure is like for your third option, the overturning type jack, and how it operates ； This is a pressure vessel, so it’s not possible to weld lifting lugs onto it by oneself ； I think it would be to create something similar to a clamp that fits around the flange of the cylinder, with lifting lugs on the clamp; I’m not sure if this approach would work.
For the third format, since no relevant information was found, I’ll draw a simple sketch for you to take a look at. To add, first of all, there are many different tonnage levels for slings; those capable of handling ten or twenty tons are no problem at all. Second, pressure vessels are not allowed to be welded directly on their main body, but welding on the gussets or backing plates, as well as the protective plates of the platform structure, is acceptable. You want to use a hoop-type structure; unless welding is used, the external force applied to the container itself is significant, which can more easily cause deformation of the equipment and lead to slipping.
Our factory workers use cloth bags for packing; steel wires are too thin