How does temperature affect your expansion joint?

Temperature basics. Of primary importance is the temperature at which the system will normally operation.  The maximum continuous system operation temperature may not be synonymous with “design temperature.”

Typically, a “design temperature” includes a significant factor, and may result in the selection of a material, or combination of materials, that is not optimized for the specific application.

It is important to distinguish between the Maximum Continuous System Operation Temperature (MCSOT) and an upset or excursion temperature. CEJ expansion joints are designed to operate at a specific “normal’ operation temperature (MCSOT).  This enables the designer to select the most efficient combination of materials for each application.

Specifying a “Design Temperature” which includes excessive safety factors may actually be detrimental to the design of the flexible element and should be avoided.

Realistic exclusion temperatures and accurate duration periods of an upset condition must be specified. The lowest temperature condition, such as during a winter shutdown, is also an important design consideration.

The presence of high heat generating equipment or components, such as adjacent uninsulated duct work, may have an effect on design and should be specified.

Insulation and condensation within the ducting. High temperature ducting systems are frequently insulated to conserve energy and help prevent internal condesnation and corrosion of the ducting. Properly designed expansion joint elements emit these criteria. Poorly designed components will promote problems. The following examples help illustrate correct design methods for expansion joints and ducting insulation.

Insulating layers. The thermal barrier of a multilayer fabric element must resist heat, moisture and acid attack. Additional retaining layers must be made of materials which remain strong and flexible when exposed to high temperatures, acids or condensates resulting from operation at or below the dew point.

At CEJ, we dedicate our efforts to provide quality custom expansion joints, to all of our customers. No job is too big or too small. Call us today to start the design process at 1-800-235-9259 or, feel free to email us too.

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