Are you dealing with the issue of the same pump failing repeatedly? No matter how many times the pump has been properly repaired or has been installed and aligned accurately in the first place, the failures keep on occurring again and again. It sure is really frustrating.

It has been observed that such an issue is generally caused by vibrations coming from other equipment in the piping system. This vibration traveled along the pipes and over a period resulted in repeated pump failure. So, what can be done to prevent this redundant issue from happening?

The answer is expansion bellows for pipes. Also referred to as expansion joints are mechanical devices engineered to absorb vibrations and dimensional changes caused by contraction and thermal expansion of a pipeline, vessel or duct while containing the system pressure.

Expansion bellows contain one or more metal or rubber made bellows that is the core element in this device. The bellows perform the function of contracting or expanding to absorb thermal movements and vibrations. It is used in varied applications across industries.

Continue to read till the end to learn more about expansion joints and how it is important for piping systems.

Why Installation of Expansion Joints in Piping Systems Important?

With the use of piping expansion joints, users are able to serve different purposes. Upon their installation correctly in the piping system, they can offer -

·         To reduce mechanical vibration and noise.

·         To absorb movements, whether it is thermal or even compressions.

·         To compensate for misalignment.

·         To relieve strain and stress that comes with the piping system.

·         To avoid electrolysis between dissimilar metals.

·         To minimize piping loads on the equipment nozzles.

With just an installation of expansion bellows, users are able to get rid of a plethora of issues that tends to impact the piping system in general.

What are the Main Components of an Expansion Joint?

The following components generally constitutes an expansion joint and they are -

·         Bellow

·         Flanges

·         Tie Rods

·         Shipping Bar

·         Internal Liners and Protective Covers

·         Additional special attachments such as Pantographic Linkages, etc.

Bellows

Bellows are the most important component in a piping expansion joint and are the basic unit for every expansion joint. Usually there are two types of bellow found and they are -

Formed Bellows and Fabricated Bellows. Formed Bellows are created from a thin-walled tube containing only longitudinal welds. Whereas, fabricated bellows are a series of thin gauge discs welded simultaneously. Also this type of bellow uses heavier gauge materials than formed bellows.

No matter which manufacturing method is used, all bellows have the same basic components and are available either in multi-ply or single-ply design.

End Connections of the Expansion Joint

There are essentially three types of end connections that are available in expansion joints to attach them with the piping system. These are -

Flanged Ends that included special flanges, angle flanges or slip-on. Vanstone Ends are a type of advanced flanged ends that brings more flexibility and aims to resolve the bolt-hole misalignment issue. Third is the Welded Ends that comes handy in use for directly welding any pipe or duct to such bellows.

Tie Rods

Tied Rods are basically bars or rods that are attached to the expansion joints assembly. These rods are engineered to absorb pressure loads and other external impacts such as dead weight.

Sometimes the use of tie rods can be as Limit Rods that safeguards the bellows from movements in excess of design that occurs occasionally due to failure of the anchor or the plant malfunction.

Internal Liners and Protective Covers

In order to protect the expansion joint components from external forces, they are placed inside a metallic cover. While the internal liners are provided to reduce the flowing media effect on the bellow’s liner surface.

Along with the internal liners, purge connections are also provided to minimize the bellow’s surface temperature while they are used in high temperature applications such as catalytic crack bellows. Normal steam or air can be used for purge medium. Purging enables flushing out the particulate matters present in between the liner and bellows. Also, harmful build-up of solids in the convolutions can be avoided with the help of purging.

Special Attachments (Pantographic Linkages)

Pantographic linkages are a scissor-like device. This is a specialized control rod attached to the expansion joint assembly. They are mainly used to offer positive distribution of thermal movement equally between two bellows of the global joint throughout its full range of movement. However, users must keep this in mind that they are not intended to restrain pressure thrust.

Available Expansion Joint Materials

The material with which the bellows of the expansion joint is made of, is an important factor to consider when it comes to decide the design of piping expansion joint. Some of the factors that can influence in selecting the suitable expansion joint bellow material are -

Manufacturing Properties - Forming and cold working capabilities along with cost and material availability.

Corrosion Properties - Surrounding environment, process media and internal cleaning agents.

Mechanical Properties - Cryogenic service, high-temperature service and operating stresses.

Expansion joints are available in non-metallic and metallic materials. While there are other materials available as well, some of them are -

·         Stainless Steel

·         Glass Fiber

·         High-grade nickel alloy steels

·         PTFE or Teflon

·         An elastomer such as rubber

Pick Your Choice of Expansion Bellows for Piping System

There are many high-end expansion bellows for pipes suppliers that offer an extensive range in their catalog. If you are searching for a suitable supplier then make sure to look for the one that offers specially designed expansion joints that are fitted for a specialized application.

Go for the suppliers that have already earned their name in the business and have supplied products to a sufficient number of projects. After all, only with the installation of best expansion bellows, users are able to prevent the high-pressure pump issues and keep the pipeline system running smoothly.

So, what are you waiting for? Make sure to do your fair share of research and find the best suppliers for expansion bellows for piping systems.