The expansion joint counteracts the pressure thrust at the equipment’s pipe outlet
Thread Content
Recently, I read some information on expansion joints. It states that the pressure force generated by a free-type expansion joint is transmitted to the mounting frame or the equipment at the elbow, and this force can be calculated using the formula F=P*A. However, using this formula results in a force acting on the equipment’s pipe connection that often exceeds the load the equipment can withstand. I noticed that in the formula, A refers to the effective area of the expansion joint; for the mounting frame at the elbow, this force acts entirely on it. But for the equipment, since the pipe connection on the equipment is also hollow, shouldn’t the force acting on it be calculated using a different formula than F=P*A, perhaps a smaller value?
It’s all based on the formula F=P*A. Your understanding of the force exerted by a blind plate isn’t thorough enough; that’s why you think the pipe opening is empty and therefore the force is small... Your understanding is incorrect. As the name implies, the force generated by a blind plate arises where there is a cross-sectional break (such as at an elbow)； For the elbow section, it’s easy to understand. However, the device outlet also requires a cross-section; since the device outlet is hollow, it is possible for a cross-section to extend into the interior of the device. The blind plate force generated at this cross-section is also transmitted (in whole or in part) to the flange at the outlet. The base of the equipment itself may absorb part of that blind plate force; as a result, the blind plate force transmitted to the pipe flange may also be less than F=P*A.
Thank you. I realize what you’re saying, but it wasn’t expressed clearly; I just don’t know how to account for the force of the blind plate in this part
F=P*A is generated by expansion joints; in the case of free-type expansion joints, this force of F=P*A is transmitted to the pipe supports or equipment, and it must be taken into consideration. However, with a pressure-balancing expansion joint, F=P*A can be balanced by the tie rods built into the expansion joint itself, and it is not transmitted to the pipe supports or equipment.
I’m studying it~ I’ve been working on this thing lately; it’s extremely troublesome
Use a pressure-balanced expansion joint if there is enough space.
Use a pressure-balanced expansion joint if there is enough space.
For calculations related to expansion joints, feel free to contact me
Hinged expansion joints can also be considered, but they need to be used in groups