Question

81: The value of axial trust in herringbone gears is
2557883145
Zero
Very high
Very low
None of these​

Answer 1

Zero.

Because, the arrangement of Herringbone gears do not produce/develop any additional axial thrust in the system. The axial thrust in the system will be the same even after the Herringbone gears arrangement.

Explanation:

• Herringbone gears are helical gears with left- hand and right- hand helix.
• This, unlike, double-helical gears, have no gap between the helix of both hands.
• It is used for transmitting power smoothly, in-between parallel shafts.

• It is developed to overcome the high-end thrust disadvantage of single-helical gears. The axial force developed in the system will be the same even after the arrangement of herringbone gears. No additional axial thrust will be developed.

• The arrangement of Herringbone gears, cancels out axial thrust on each set of helix due to which larger helix angles can be used.
• Herringbone gears are prepared or manufactured, where, the blank is mounted on axis horizontal in an index driven by the spindle.
• The cutters in Herringbone gears are rotated by the index on time.
• The arrangement of Herringbone gears also eliminates the need for thrust bearings.
• Also, the side thrust of one helix is balanced by another helix in the Herringbone gears.
• This is why, the introduction of these gears is very much important in steam turbines for marine propulsion.