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Why Choose Spiral Bevel Gears?

By June 23, 2021No Comments

What are Spiral Bevel Gears?

Spiral bevel gears are bevel gears whose axes intersect, often at a 90-degree angle. The teeth are cut with a slight curve along their length and an involute profile. Although they can be considered a hypoid gear, they have no offsets. 

What makes Spiral Bevel Gear Unique?

Spiral bevel gears are often used to transmit power through a right-angle. They are well suited for heavy-duty applications and can be designed for high-speed operations.  Relative to some of the alternative bevel solutions, they can reduce the cost of ownership by providing longer-lasting performance and minimal need for repairs or replacements 

Due to the geometry of the gear teeth, spiral bevel gears are more compact relative to their load rating, as well as more efficient than other types of right-angle gears.  AGMA (American Gear Manufacturers Association) and the other associations around the world, define gear standards which include a system for describing the quality of gears.  Amarillo Gear Company’s gears and gearboxes are designed to meet or exceed AGMA standards for a given service factor.   As the quality of a spiral bevel increases, the efficiency increases, noise produced decreases, heat generation is reduced and vibration from their operation is lessened.  Under the right conditions, a higher quality spiral bevel gear set can reach 99% efficiency.  

Summary of Benefits of using Amarillo Gear Company’s Spiral Bevel Gears:

  • Higher Efficiency – The calculated efficiency of our spiral bevel gear sets are 96% to 98%, which is greater than that of other types of right-angle gear sets.  This means more of the power from the prime mover is used to perform work and not generate heat.  (The efficiency depends on the quality number, ratio, duty cycle, and other factors.)
  • Greater Power Density – Spiral bevel gears are more compact for their rated power than the other types of right-angle gears.
  • Smaller Space Claim (volume) –Their higher power density means the gearboxes that use spiral bevel gears can be designed to be smaller than transmissions that do not incorporate them.  This results in lower weight, less space and lower overall cost. 
  • Minimal Vibration – The shape of the spiral bevel gear teeth allow the gears to engage each other gradually and smoother than some of the alternative options.  Therefore, a spiral bevel gear set will generate less vibration than other right-angle bevel gear sets with the same rating and similar finishing of their teeth.  
  • Less Heat – The greatest source of power loss (efficiency) in a bevel gear set is from heat generated by the interaction of the gear teeth.  The lower relative heat reduces the need for cooling of the oil and improves the operating life of the lubrication.
  • Higher Torque  – A spiral bevel gear has more surface area in contact than a straight or zerol bevel, for the same pitch diameter.  The larger contact area means more power can be transmitted without exceeding the allowable stress of the alloy steel.  
  • Better Life – By distributing the load over a larger area, the spiral bevel gear will result in a relatively lower contact stress in the gear teeth and lower bending moment at their root. This provides the spiral bevel with a longer design life (pitting and bending) than the other types of right-angle bevel gears of the same size.
  • Higher Speed – The higher quality spiral bevel gears can be operated at relatively high speeds.  

Amarillo Gear has been designing and manufacturing gears for 90 years, in Amarillo, Texas.  All gear processing is in-house including gear blanking, tooth generation, heat treating, and gear finishing. The greatest volume of our gears are used in our Pump Drives and Cooling Fan Drives.  We also provide open gearing for industrial applications that include roller mills, cone crushers, marine transmission systems, off-highway transmissions, bow thrusters, and drill rigs.

All gear processes are “in-house” and controlled by internal quality processes which are certified by LRQA to ISO 9001:2015 standards. Many sizes and ratios are in stock for immediate delivery. We will either manufacture your design, reverse engineer or create a new design to meet your large diameter spiral bevel gear application.

If you’re in need of bevel gears, or you’re ready to learn more, contact Amarillo Gear Company today!