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Consider the following statements: The axis of spiral bevel gear are non-parallel and intersecting. 1) The most common pressure angle for spiral bevel gear is 20° 2) The most common spiral angle for spiral bevel gear is 35. 3) Spirals bevel gears are generally interchangeable. 4) Spirals are noisy and recommended for low speeds of 10 m /s. Which of the above statements are correct?

Consider the following statements: The axis of spiral bevel gear are non-parallel and intersecting. 1) The most common pressure angle for spiral bevel gear is 20° 2) The most common spiral angle for spiral bevel gear is 35. 3) Spirals bevel gears are generally interchangeable. 4) Spirals are noisy and recommended for low speeds of 10 m /s. Which of the above statements are correct? Correct Answer 1 and 2

Explanation:

Spiral bevel gears are used to connect two intersecting shafts. Spiral bevel gears have teeth inclined at an angle of the face of the bevel. Spiral gears have a spiral angle of 35° usually and the pressure angle varies from 14.5° to 20°.

Spiral gears offer the following advantages

  • There is a gradual contact between mating teeth therefore there is a smooth and quieter operation.
  • It has more load-carrying capacity because more teeth are in contact at a time and there is a greater arc of contact.
  • It permits higher operational speeds.
  • The spiral bevel gears if made within one system then only they can be interchangeable otherwise they are interchanged with the sets together.

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