The Working Principle Of Expansion Joints

The working principle of expansion joints is based on the elastic deformation characteristics of their bellows. When a pipeline system expands or contracts due to factors such as temperature changes, medium flow, or installation errors, the bellows will elastically deform accordingly, absorbing and compensating for these deformations, thereby protecting the pipeline system from stress damage. Specifically, the working principle of expansion joints can be divided into the following steps:

Deformation Sensing: The expansion joint senses the expansion and contraction deformation of the pipeline system through its bellows. When the pipeline system deforms, the bellows will be subjected to corresponding stress.

Elastic Deformation: Under the action of stress, the bellows will undergo elastic deformation, and its corrugated shape will change, thereby absorbing and compensating for the expansion and contraction deformation of the pipeline system.

Restoration to Original Shape: When the deformation of the pipeline system decreases or disappears, the bellows will gradually return to its original shape using its elastic restoring force, preparing for the next deformation compensation.

Limit Protection: During the operation of the expansion joint, the tie rod and limit device play a protective role, preventing the expansion joint from being damaged due to excessive expansion and contraction. When the expansion joint reaches the set value, the pull rod will limit its further extension and contraction, while the limiting device will prevent the expansion joint from moving excessively in a certain direction.