Differences between metal expansion joints and non metallic expansion joints

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• 1.Their advantages are different, non-metal expansion joints(rubber and fabric expansion joints) have the characteristics of corrosion resistance, high temperature resistance, noise reduction and vibration reduction. While metal expansion joints have better performance and compact structure.

2. Different in main application fields. Non metallic expansion joints are especially suitable for hot air ducts, smoke and dust ducts, and other fields.Metal expansion joints are mainly used in metallurgical chemical industry, nuclear energy and other fields.

3.Different compensation functions: Under the same overall dimensions, the compensation function of non-metal expansion joints is much larger than that of metal expansion joints. Especially for the compensation function of lateral displacement, the compensation function of non-metallic expansion joints is almost an order of magnitude larger than that of metal expansion joints.

• 4. Different in compensation ability: Expansion joint is like an elastic body, after being contracted or stretched, it will generate resistance. The resistance of metal expansion joints will be much larger than that of non metallic expansion joints. But if this resistance is too large, will detrimental to the system and damage the surrounding equipment, must choose the right expansion joints.
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5. High temperature resistance and corrosion resistance: The material of non-metal expansion joint not only has good high temperature resistance, but also has excellent acid resistance. Ordinary carbon structural steel in 600 degrees’ environment, the yield limit is equal to 0,if more higher, it will oxidize and peel. Carbon steel expansion joints are easy to crack during work engineering, and stainless steel expansion joints will suffer from low dew point corrosion in low temperature environments, and their cost is also considerable.

6. Thermal insulation and energy saving performance: The structure of non-metal expansion joints has thermal insulation properties, but metal expansion joints do not have this condition. In order to keep warm, the outer layer of the expansion joint is also covered with a thermal insulation layer.