Double Helical Gear

What is a Double Helical Gear?

A double helical gear, also known as a herringbone gear, is a type of gear composed of two helical sections with opposite helix angles. This design eliminates axial thrust, providing smooth and efficient power transmission with high load capacity and minimal noise. It is widely used in heavy machinery, automotive systems, and industrial equipment where precision and durability are critical.

Key Features of Double Helical Gears

Elimination of axial thrust due to opposed helix angles
High load-bearing capacity and torque transmission
Reduced noise and vibration compared to spur gears
Enhanced efficiency and smooth operation
Suitable for high-speed applications
Durable construction with materials like steel, bronze, or composites

Product Parameters and Specifications

Our double helical gears are manufactured to meet rigorous industry standards, ensuring reliability and performance. Below are the detailed parameters available in our product line.

Standard Parameters List

Module Range: 1 to 20 mm
Pressure Angle: 20° or 14.5° (customizable)
Helix Angle: 15° to 30° (standard), adjustable per requirement
Gear Ratio: Up to 10:1 for single stage, higher with multi-stage setups
Material Options: Carbon steel, alloy steel, stainless steel, bronze, nylon
Heat Treatment: Carburizing, nitriding, induction hardening available
Accuracy Grade: DIN 5 to 9, AGMA 10 to 13
Maximum Diameter: Up to 2000 mm
Operating Temperature: -40°C to 150°C (wider ranges with special materials)
Surface Finish: Ground, shaved, or honed for precision

Detailed Specifications Table

Parameter	Standard Value	Custom Range	Applications
Module (mm)	2, 4, 6, 8	1 - 20	General machinery, automotive
Number of Teeth	20 - 100	10 - 200	Varies by design
Face Width (mm)	20 - 200	10 - 500	Heavy-duty equipment
Helix Angle (°)	23	15 - 30	High-speed drives
Material Hardness (HRC)	58 - 62	20 - 65	Industrial gearboxes
Max Torque (Nm)	5000	Up to 20000	Mining, marine applications
Noise Level (dB)	< 75	Customizable	Precision instruments

Advantages of Using Double Helical Gears

Double helical gears offer several benefits over other gear types, making them ideal for demanding applications. Their balanced design reduces wear and extends service life, while the absence of axial thrust allows for simpler bearing arrangements. This results in lower maintenance costs and higher operational efficiency.

Frequently Asked Questions (FAQ)

What is the main advantage of a double helical gear over a single helical gear?
The primary advantage is the elimination of axial thrust. In single helical gears, the helix angle creates axial forces that require thrust bearings, but double helical gears counterbalance these forces, leading to smoother operation and reduced bearing complexity.

How does the helix angle affect gear performance?
The helix angle influences the gear's torque capacity, efficiency, and noise level. A higher helix angle provides smoother engagement and higher load capacity but may increase axial thrust if not balanced (as in double helical designs). Standard angles range from 15° to 30° for optimal performance.

What materials are commonly used for double helical gears?
Common materials include carbon steel for general use, alloy steel for high strength, stainless steel for corrosion resistance, bronze for low friction, and polymers like nylon for lightweight and quiet operation. Material selection depends on application requirements such as load, speed, and environment.

Can double helical gears be customized for specific applications?
Yes, they can be customized in terms of module, helix angle, material, heat treatment, and accuracy grade. Custom designs are available for industries like aerospace, marine, and mining, where specific performance criteria must be met.

What maintenance is required for double helical gears?
Regular maintenance includes lubrication checks, inspection for wear or damage, and alignment verification. Due to their robust design, double helical gears typically require less frequent maintenance than other gears, but adherence to manufacturer guidelines is essential for longevity.

How do I select the right double helical gear for my application?
Selection depends on factors such as load capacity, speed, operating environment, and space constraints. Consulting with engineering specifications and possibly performing stress analysis is recommended. Our team can assist in choosing the appropriate gear based on your needs.

Are double helical gears suitable for high-speed applications?
Yes, their balanced design and smooth tooth engagement make them excellent for high-speed operations, such as in turbines or precision machinery, where minimal vibration and noise are critical.

What is the typical lifespan of a double helical gear? With proper maintenance and under normal operating conditions, double helical gears can last for decades. Lifespan varies based on material, load, and environment, but they are known for their durability and resistance to wear.