Stress analysis of heat transfer oil pipelines
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For two DN250 heat transfer oil pipes running side by side at 260 degrees, what layout should be adopted when installing them in a 200-meter-long light steel structure workshop of Class C? Should natural compensation or a corrugated compensator be used? How should horizontal stress be calculated? Is there a simpler way to calculate it?
It’s been two days and no one has responded yet; I’ll share my personal opinion first. Firstly, since it is a light steel structure factory building with relatively large spans and lengths, using axial bellows compensators would result in significant thrust forces; in particular, there might be horizontal thrust forces of five to six tons at each end. After consulting a structural engineer, it was determined that such a light steel structure might not be suitable for this purpose. Therefore, natural compensation is being considered. Given that the height of the factory building is 11 meters, if a \"U\"-shaped compensator is used with H=4m and A=6m, would it be sufficient to install a fixed support every 27 meters? Well, there is another issue regarding horizontal thrust that cannot be determined: there is an L-shaped bend at the end, so what is the horizontal thrust exerted by the fixing bracket at that point? Is there a simple way to calculate it or a table to consult for this purpose?
I think it’s not that using wave compensators is not an option; rather, the axial type has a greater thrust, so a pressure-balancing type can be chosen, which eliminates the thrust exerted by the blind flanges. Natural compensation can also be used, but it requires more space, and the fixing brackets are more complex. For your pipeline, as long as the right type is selected, adding a few compensators will suffice. What are the specific parameters of the end L-shaped bend, and how long is it? It should be easy to calculate.
The L-shaped bend is about 30 meters long. With the use of wave compensators, the horizontal thrust at the center, when arranged symmetrically, will be very small; however, greater thrust will occur at both ends. I wonder to what extent the pressure-balancing type you use can reduce this thrust The conditions are in the first post.
This post was last edited by dwx expansion joint dwx on 2012-3-26 at 17:33. I didn’t do the calculations before; regarding the issue mentioned at the top, if a pressure-balancing type compensator is used, there is no internal pressure thrust, only displacement thrust. Assuming a fixed support every 27 meters and designing for a pipe pressure of 1.0 MPa, the thrust on each fixed support should not exceed 3 tons. I’m not sure whether your light steel structure can withstand that For that L-shaped bend, how long are the long arm and the short arm respectively? It would be best to have a piping layout diagram; displacement compensation might also be necessary, and calculations are required. The above are just my suggestions for reference; you should make a reasonable choice based on the actual situation. I hope this will be helpful to you.
Just find a friend and use the stress analysis software CAESARII to do the calculations – it’s best to use the best available method: first install the pipes vertically, and then have them run horizontally in the lateral direction; this arrangement results in better stress absorption!
Moving horizontally might take up more space; I think it’s better to apply vertical compensation. It would be very troublesome to use software for analysis every time, especially since it seems there’s no cracked version of this software… That’s why I’m looking for a simple method that allows calculation by hand. I earnestly ask experts for advice
Waiting for an expert to solve this. Also, isn’t 27 meters too close as a fixed distance?
The Pipedate software has a tool for calculating pi-shaped bends. Take a look next. It’s available on our forum.
It seems that there are only details such as the dimensions of various elbows, tees, etc., as well as the dimensions and weights of valves and flanges; there isn’t much calculation regarding the compensation for elbow bends or the horizontal thrust
Looking forward to experts too! Since the pipe diameter is DN250 and the temperature is very high, if the spacing between the fixing brackets is too large, the amount of compensation required will inevitably be significant. As a result, the H value for the elbow shape will be large, and the horizontal thrust will also be high; all of these factors make it difficult to arrange the equipment inside the plant as well as to design the piping system