The Characteristics And Application Fields of Herringbone Gears

The herringbone gear is a specially designed double helical gear, with its teeth arranged in a "person" shape. The helical angles on the left and right sides are symmetrical but opposite in direction. This structure endows it with both high load-bearing capacity and smooth transmission characteristics, and it is widely used in heavy machinery, ships, energy and other fields

The characteristics of large herringbone gears

1. High load-bearing capacity

   The double helical structure of herringbone gears enables the load to be distributed over more tooth surfaces. Compared with helical gears, the load-carrying capacity is increased by 30% to 50%.

   The axial forces cancel each other out, reducing the axial load on the bearings and prolonging the service life of the equipment.

2. It operates smoothly with low noise

   The symmetrical helical Angle design eliminates the axial thrust of helical gears, significantly reducing vibration and noise, and is suitable for high-speed and heavy-load working conditions.

3. High transmission efficiency

   The contact area of the tooth surface is large, the sliding friction is small, and the efficiency can reach over 98%.

4. The manufacturing is complex and the cost is high

   It requires special machine tools (such as herringbone gear milling machines) for processing, and has strict requirements for tooth profile accuracy and assembly.

Main application fields

1. Shipbuilding industry

   Reducers used in ship propulsion systems (such as large cargo ships and warships), which transmit large torque and need to be resistant to seawater corrosion.

2. Energy equipment

   Hydroelectric generating units (turbine drive), wind turbine speed-increasing boxes, and nuclear power plant circulating pump drive devices.

3. Heavy machinery

   Low-speed and heavy-duty equipment such as mine crushers, steel rolling mills and cement mills.

4. Aerospace

   The transmission systems of some aircraft engines require a combination of lightweight and high strength.

5. Chemical Engineering and Metallurgy

   Power transmission components for large compressors and blowers.

Design and manufacturing difficulties

1. Tooth profile processing

   A CNC forming gear milling machine or gear grinding machine is required to ensure the symmetry and accuracy of the left and right helical teeth (ISO 1328 standard).

   Tool retreat groove design: Some herringbone gears have a tool retreat groove in the middle for convenient processing, but it will slightly reduce the strength.

2. Material selection

   Common alloy steels (such as 20CrMnTi, 42CrMo) undergo surface carburizing, quenching or nitriding treatment to enhance hardness (HRC58-62).

3. Thermal deformation control

   Large gears are prone to deformation during heat treatment and require staged quenching or laser correction processes.

4. Assembly requirements

   Precise alignment is required to avoid uneven loading on the tooth surface due to misalignment.

Future development trend

1. Integrated design: Formed in one piece with bearings and housing to reduce assembly errors.

2. Intelligent monitoring: Embedding sensors to achieve real-time health diagnosis.

3. New material application: Exploration of carbon fiber composite materials or Ceramic-coated gears.