Rubber expansion joints provide a dependable, low-maintenance, economical solution for piping system movement. They absorb anticipated pipe movements or displacements, compensate for misalignments, reduce noise and vibration, and have a life cycle in the tens of millions. They may also be able to reduce abrasion or erosion and resist corrosive media.
A rubber joint is a flexible connecting piece made of natural and synthetic elastomer and fabric that reduces thermal movement and mechanical vibration in piping systems. It can be reinforced with internal metal and can be designed to meet specific requirements, such as pressure, temperature and fluid characteristics.
There are several types of rubber expansion joints, each designed to suit a particular application. They can be manufactured manually or by molding processes. Some molded expansion joints have solid rings or wire embedded in the carcass to increase the strength of the joint for extreme pressure or vacuum.
Types of Rubber Expansion Joints
There are a variety of designs that allow for a wide range of movements. They include single arch, multiple arch, and ball joints. Each type of rubber joint is based on the type of service required and its ability to absorb axial, angular, lateral, and torsional movement.
Some type of flange face seal is often used to form a tight fit between the metal flange and the joint without the need for gaskets. It is possible to paint the flange face with a solution of graphite in water or glycerin to help prevent adherence between the joint and the pipe flanges.
It is important to check the integrity of the flange cover before placing the expansion joint into service. It is also important to check the alignment and support of the piping before installing it. If piping is not lined up properly or not supported, it could cause the joint to collapse, resulting in leaks and damage.
During the installation process, the flanges should be cleaned of any debris or dust that might accumulate. After they are in place, lubricant should be applied to the face of the flanges to aid in their operation. It is best to use a solvent-based oil-free lubricant.
In addition to the flanges, it is important to check that the joint is fully installed and that all gaskets are intact. If not, the flange faces may become loose or the joint may swell and collapse during operation.
There is no need to install a rubber joint without performing regular inspections. This will ensure that the joint is not damaged and will lower the chances of leaks, corrosion or blisters developing.
A routine inspection program is a good idea, but this can be difficult to implement. A FEA model can be created to predict the joint’s behavior under various loading conditions and help ensure that the design is sound.
Using this model, the product can be produced more efficiently and accurately than by manually manufacturing it. The design is then optimized for the production machine by using smart point filtering and path optimization.