Application example of the hottest bellows expansi

Application example of bellows expansion joint

different types of expansion joints have different displacement compensation functions. In the pipeline design, the type selection can be given according to the structure and pressure of the pipeline. 1. Working principle of fatigue testing machine: comprehensive consideration with parameters such as diameter

compensation of axial displacement

Figure 1 is a good typical example of using a single expansion joint to absorb the axial expansion of the pipeline, which can not be achieved by hydraulic experimental machines anyway

Figure 2 is a good typical example of using a compound expansion joint to absorb the axial expansion of a pipeline

Figure 3 is a good typical example of using expansion joints to absorb the axial expansion of pipelines with branch pipes

Figure 3

Figure 4 is a good typical example of using expansion joints to absorb the axial expansion of pipelines with reducers

figure 4

Figure 5 shows the method of using expansion joints on a pipeline containing "Z" shaped pipe sections

figure 5

figure 61.71 ~ 2.00 is a good typical example of using elbow pressure balanced expansion joint to absorb axial expansion of pipeline

figure 6

Figure 7 shows how to use the straight pipe pressure balanced expansion joint to absorb the axial displacement on the long straight pipe section

Figure 7

figure 8 is a good typical example of using elbow pressure balanced expansion joints to absorb the thermal expansion of steam turbines, pumps, compressors and other equipment. The main function of the expansion joint is to reduce the load acting on the equipment shell

figure 8

compensation for lateral displacement, angular displacement and their combined displacement

in the case of lateral displacement, angular displacement and their combined displacement, the correct selection and use of expansion joints need to take into account the configuration of the pipeline, operating conditions, expected cycle life, bearing capacity of the pipeline and equipment, structures that can be used for support and other factors. In some cases, there may be several kinds of expansion joint equipment placed at the ambient temperature suitable for the same application. At this time, you can simply consider which one to choose based on economy. However, it is more common that in all kinds of feasible designs, one or another should be considered to be unique, especially suitable for use in some specific occasions

(1) single expansion joint

Figure 9 and figure 10 are typical examples of using single expansion joint to absorb axial and lateral combined displacement

Figure 11 and Figure 12 replace the main fixed supports at both ends of the expansion joint in Figure 10 with connecting rods

(2) universal expansion joint

universal expansion joint is particularly suitable for absorbing lateral displacement. In addition, this design form can also be used to absorb axial displacement, angular displacement and any displacement synthesized by these three forms. The general usage of the universal expansion joint is to set the expansion joint with connecting rod in the middle pipe arm of the "Z" pipe with a 90 ° angle. Figure 13 and Figure 14 are two application examples

Figure 15 is a typical example of using elbow pressure balanced expansion joints where there is a combination of axial and lateral displacement

Figure 16 shows that elbow pressure balanced expansion joints can also be used when the pipe corners are not equal to 90 °

figure 16

Figure 17 shows a common occasion that is very suitable for using elbow pressure balanced expansion joints

figure 17

Figure 18 shows an example of using universal pressure balanced expansion joints in occasions with large lateral displacement

3) hinged expansion joints hinged expansion joints are generally used as a group of two or three to absorb lateral displacement in one or more directions in a single plane pipe system

in this system, each expansion joint is restricted by its hinge, resulting in pure angular displacement; However, each pair of hinged expansion joints separated by the pipe section cooperate with each other and can absorb lateral displacement. Give the angular displacement of an expansion joint. The lateral displacement that can be absorbed by each pair of hinged expansion joints is directly proportional to the distance between their hinge pin shafts. Therefore, in order to make the expansion joints fully effective, this distance should be increased as much as possible. The hinge of the expansion joint is usually used to bear all the pressure and thrust acting on the expansion joint

in addition, it can also be used to bear the weight of pipes and equipment, wind load or similar external forces. Figure 19 shows how to absorb the main thermal expansion of a single plane "Z" bend with a double hinge system

if the flexibility of the single plane pipe system is not enough to absorb the bending deflection of the double hinged system, or the load generated by bending exceeds the allowable limit of the connecting equipment, the system with three hinged expansion joints can be used

Figure 20 shows the three hinge system in the single plane "Z" shaped elbow. The thermal expansion of the vertical pipe section will be absorbed by the action of two expansion joints B and C. Therefore, it is obvious that the expansion joint B must be able to absorb the rotation formed by the two expansion joints a and C

figure 21 illustrates the working principle of using hinged expansion joints when the elbow angle is not equal to 90 °. Here, we only need to use the middle fixed support plane guide support

Figure 22 illustrates an example of using hinged expansion joints when the connecting equipment also produces plane displacement

Figure 22

figure 23 shows an example of the application of hinged expansion joints in the equipment and pipeline connection system

(4) universal hinged expansion joint

just as hinged expansion joint has great advantages in plane piping system, universal hinged expansion joint has similar advantages in space piping system. Universal hinged expansion joints have the ability to absorb angular displacement in any plane. They are often used to form a pair to absorb lateral displacement. Figure 24 shows an application example

if it is impossible or not intended to use the bending of the pipe to absorb the extension of the vertical pipe arm, a system consisting of two universal hinged expansion joints and one hinged expansion joint can be used as shown in Figure 25

figure 25

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