To safely accommodate thermal expansion and contraction in a tube assembly, it ought to be______________?
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Answer: D. bent
Explanation
Thermal expansion and contraction cause rigid pipelines and tube assemblies to change length significantly with temperature. Incorporating engineered bends or expansion loops provides mechanical flexibility to absorb these dimensional changes safely. Bending sections act as flexible springs that relieve thermally induced stresses without buckling or fracturing tubes. Materials expand when heated and contract when cooled, generating substantial internal forces in constrained assemblies. Rigidly anchored straight tube runs subjected to temperature swings experience massive compressive and tensile thermal stresses. Flexible mechanical design techniques protect piping networks from fatigue failure caused by repeated thermal cycles.
Power plant steam headers and chemical plant piping utilize expansion loops and bends to manage thermal movement. Automotive exhaust systems feature flexible bellows and bends to accommodate engine vibration and thermal growth. HVAC ductwork and refrigeration tubing require careful routing with bends to prevent thermal stress damage. Crimping deforms tube ends for mechanical joints rather than providing flexibility for thermal expansion. Honing is an abrasive machining process used to finish internal cylinder bores rather than accommodate thermal movement. Flaring widens tube ends for compression fittings, which does not provide thermal expansion flexibility.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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