There are many types of ripple compensators, which can be divided into several different categories according to different standards. If they are classified according to whether they are binding on internal pressure thrust, they can be divided into constrained type and free type ripple compensators.
The constrained type is that the bellows compensator itself can constrain the pressure thrust generated by the pipeline fluid (that is, it can eliminate the axial force generated by the medium pressure on the fixed support), while the free type, on the contrary, cannot constrain the pressure thrust.
The pressure balanced corrugated compensator is usually preceded by the words "balanced", "pressure balanced" and "thrust free" before the "sleeve". Its structural types are divided into bypass type, piston balanced type and balanced angle type from the principle of eliminating the axial force of the medium.
The thermal elongation of the pipe is compensated by the movement of pipe A in the sleeve. The medium flow is not directly from pipe A to pipe B, but through the bypass pipe. In this way, there is a pair of A and B heads in a compensator, and the horizontal thrust F1 and F2 generated by the medium pressure are balanced in the compensator. This structure can also be regarded as the type of directional compensator, and the pipe expansion and contraction adopts the sleeve type structure.
The piston automatic balancing compensator is equipped with an annular piston outside the core tube, and makes the total area of the piston equal to the sectional area of the core tube, which is the technical core to achieve automatic balancing. The stress analysis of this structure is as follows:; Assuming that a section of pipe is installed with "piston automatic balance compensator", F1 and F2 are the axial thrust generated by the medium pressure, which are opposite in direction and equal in size. These two forces act on the left and right connecting pipes of the sleeve respectively. If they cannot be balanced, they should be respectively.
The fixed supports on the left and right pipes bear. Now an additional piston body is used. The medium in the piston body is connected to the pipe through the connecting hole 3. The medium pressure also acts on the piston body 1. The area of the piston is equal to the sectional area of the pipe, so F1 ＝ F1. F1 is connected to the left sleeve through the piston rod. F2 and F1 are a pair of force and reaction forces, equal in size and opposite in direction.
So F2=F1, F2=F1. In this way, the two pairs of forces are equal in size and opposite in direction, acting on a straight line, so that the axial force generated by the medium pressure can be balanced. During the pressure test of the above two structures, the problem of pulling to the east will no longer occur, and the sleeve will not move relative to the installation position, which is convenient for construction and installation. The compensation function of the balance angle structure is realized by the movement of the core tube. Because the blind plate appears at the end of the core tube when the medium flow turns, the axial force generated by the medium in the pipe section is balanced at both ends. There are two basic types of corrugated compensator structure.
