Metal expansion joints can handle demanding conditions

Large industrial pipes in a thermal power plant

Northern Industrial Supply Co. (NISCO) can provide a range of expansion joints. The selection includes several types of elastomer expansion joints such as piping, flue duct and high temperature varieties. But when it comes to applications with the most demanding conditions, the company provides metallic expansion joints.

Many types for demanding applications

These expansion joints can be used in temperatures ranging from -251 to 982 degrees C (-420 to 1,800 degrees F). The high strength of metal expansion joints also allows them to handle pressures up to 1,000 psi. The joints are engineered to provide outstanding performance and can be designed to suit unique installation requirements such as movements, space, corrosion resistance and more.

Some of the different models of metal expansion joints available include single bellow, universal, external pressurized and pressure balanced types.

• Single bellow is the most fundamental type of metal expansion joint.
• Universal expansion joints have two bellows to allow for greater lateral movement.
• External pressurized joints enable a greater number of convolutions to be used without losing stability. This is because line pressure acts on the external surfaces of bellows thanks to an external pressure chamber.
• Pressure balanced expansion joints (also known as elbow and inline) have additional equalizing bellows to cancel out pressure thrust while absorbing movements.

Typical applications

Just some of the applications metal expansion joints are often used for include oil refineries, desalination plants, marine applications, wastewater treatment, fossil fuel power generation, pressure vessel manufacturing and the pharmaceutical industry.

Although the strength of metal expansion joints is needed for some applications, the downside is that they have reduced spring rates when compared to elastomer joints. For that reason, metallic joints are typically used with additional supplies, including gaskets, covers, liners and anchors.

When deciding what type of expansion joint is best suited to a particular application, NISCO can provide assistance. Contact NISCO for more information.

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