The frame of an induction motor is generally manufactured from____________?
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Answer: B. cast iron
Explanation
Cast iron provides excellent mechanical rigidity and structural strength for motor housings. It absorbs internal vibrations effectively and dampens acoustic noise during motor operation. This makes cast iron the preferred material for manufacturing durable industrial motor frames. Motor frames protect internal stator assemblies and support bearing end shields securely. Cast iron and fabricated steel are standard materials used across the electric motor industry. Thermal conductivity of cast iron also helps dissipate heat generated by internal copper losses.
Harsh industrial environments require robust cast iron frames to withstand physical impacts. Aluminum is sometimes used for smaller frames to reduce weight, but cast iron dominates heavy duty. Foundry casting processes allow manufacturers to shape complex cooling fin geometries easily. Option a is incorrect because silicon steel is used for core laminations, not outer frames. Option c is incorrect because aluminum is typically reserved for smaller frame sizes or end bells. Option d is incorrect because bronze is too expensive and structurally unnecessary for motor frames.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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