Pipe expansion joints are necessary in systems that convey high temperature commodities such as steam or exhaust gases, or to absorb movement and vibration. An expansion joint is a useful component in an infinite number of applications.
What industries use expansion joints?
A typical type of expansion joint for pipe systems is a bellows which can be manufactured from metal (most commonly stainless steel), plastic (such as PTFE), or an elastomer such as rubber.
Why should I use a pipeline expansion joint?
A bellows is made up of a series of one or more convolutions, with the shape of the convolution designed to withstand the internal pressures of the pipe, but flexible enough to accept the axial, lateral, and/or angular deflections.
Expansion joints are also designed for other criteria, such as noise absorption, anti-vibration, earthquake movement, and building settlement.
Engineers and pipe designers routinely incorporate expansion joints into their pipe systems, as expansion joints add flexibility in to the design and reduce costs through removing the complexity of fix points, guides and reduces the overall space requirements for the pipe system.
Further, expansion joints are more effective than alternatives such as pipe bends and pipe loops due to their greater ability to conserve space, their economic efficiency and better performance in absorbing larger movements.
An expansion joint is a useful component in an infinite number of applications. Metal expansion joint assemblies are commonly used for all kinds of industries and applications including:
- Power Generation
- Co-Generation, Petrochemical
- Chemical Processing
- Pulp Paper Manufacturing
- Cryogenic Process
- Pressure Vessel and heat Exchanger
- Heat Steam recovery Generator
- Architect Engineering
- Construction Engineering
- Mechanical contractor
- Pharmaceutical manufacturing
- Gas Turbine, Gas Transmission
- Diesel Engine Mfg, Incineration
- Waste Water Treatment
Expansion joints are often installed near boilers, heat exchangers, pumps, turbines, condensers, engines and in long pipe systems or pipe ducts.
What types of expansion joint types are available?
Expansion joints come in a wide variety of designs. Some of them are standard and some are customised as per client requirements.
Although their design may vary significantly, all expansion joints are nevertheless composed from some of the following components, all with one or more specific functionalities: bellows, welding ends, flanges, hinges, tie-rods, spherical washers, wire mesh, insulation, inner sleeve, external cover, elbow and/or ring reinforcement/equalizing rings.
In general, there are fabric, metallic, and rubber expansion joints.
- Metallic Expansion Joints
- Single Expansion Joints
- Hinged Expansion Joints
- Gimbal Expansion Joints
- Universal Expansion Joints
- Elbow Pressure Balanced Expansion Joints
- In-line Pressure Balanced Expansion Joints
- Externally Pressurized Expansion Joints
- Toroidal Expansion Joints
- Thick Wall Expansion Joints
- Slip-type Expansion Joints
- Rectangular Metallic Expansion Joints
- Refractory Lined Expansion Joints
- Fabric Expansion Joints
- Rubber (Neoprene) Expansion Joints
In a piping system a Expansion joints alternately known as Bellows are like sealed springs. Sealed because it is required to contain the fluid pressure which is flowing through it and spring because it is required to respond to the movement of the connected piping without offering appreciable stiffness to the piping system.
Application of Expansion Bellows:
The Bellows are generally employed in a piping system in one of the following situations:
- When the space constraints do not permit providing adequate flexibility by conventionalmethods (e. g. expansion loops etc.) for maintaining the system stresses withinacceptable limits.
- When conventional solutions (e.g. expansion loops etc.) create unacceptable processconditions (e.g. excessive pressure drop).
When it is not practical to limit the piping induced loads on the terminal nozzles of theconnected equipment within admissible limits by conventional methods. - When the equipment such as Compressors, Turbines, Pumps etc. necessitate isolatingthe mechanical vibrations from being transmitted to the connected piping.
