Since the late 1980s, Accurate Specialties, Inc. has become North America’s leading manufacturer of bronze gear blanking. We are an ISO 9001:2015-certified manufacturer and our cutting-edge horizontal and vertical turning centers allows us to produce bronze gear blanks with high precision and quality.
Accurate Specialties is a full-service bronze foundry that offers clients the following competitive advantages:
- Integrated Manufacturing
- Reduced Total Costs
- Quick Response Times
- Component Reduction
- Manufacturing Flexibility
- Engineering Design Assistance
- Complete Material Integrity
- Responsive Manufacturing
- Short Lead Times
How Are Gears Manufactured?
The most effective method for gear manufacturing depends upon a number of factors, such as manufacturer capabilities and the desired end application. There are three basic types of gear manufacturing: broaching, hobbing, and gear machining.
- Manufacturers typically employ gear broaching to produce steel shafts and splines or define unusual gear shapes. Manufacturers pull the broach cutting tool through an object. As the tool is pulled through, the size of the leading edge—or tooth—gradually increases until the intended design shape is formed.
- Gear hobbing produces small helical gears, spur gears, sprockets, and splines. Gear hobbing is a generating process, which means that the final tooth shape is not directly related to the shape or form of the cutting tool. The cutting tool (hob) and the workpiece are in a continual state of rotation during operations, gradually forming the gear teeth as the hob traverses the workpiece surface.
- CNC gear machining is a high-precision method of forming a wide range of gears, such as internal gears, worm gears, sprockets, spur gears, and helical gears. Gear machining typically involves milling or other cutting operations.
Gear Blanks for Gear Manufacturing
Gear blanking refers to the initial metal cutting operations that form a rough material into the contour of a gear part. At Accurate Specialties, we use a number of different processes for our gear blank manufacturing. These processes include:
- Chill casting: Molten bronze is poured into a die base fabricated from aluminum or steel. The lower temperature of the die causes the bronze to cool rapidly from the outside to the center. The end result is a bronze gear blank with exceptional uniformity and a particularly fine grain structure.
- Centrifugal casting: Centrifugal casting produces gear blanks with very high purity levels and a fine, dense grain structure. We spin the casting die at high speeds, resulting in generated pressure up to 60 times the force of gravity. As a result, all imperfections and impurities are channeled into a centralized riser area. After it is cooled, the centralized riser material is machined out, resulting in a gear part free of shrinkage cavities, gas pockets, and blowholes.
- Spin casting: In spin casting, a bronze rim encompasses a hub of steel or cast iron. Lugs in this hub are filled with molten bronze, creating the section of the blank that will form into gear teeth. Since the shrinkage rate of bronze is greater than that of cast iron and steel, the bronze mechanically bonds to the hub, creating a very strong bond.
- Continuous casting: This process allows for part-specific casting. Batches of molten bronze alloy flowing through a graphite mold produce continuous cast alloys, which subsequently cool in tubes or bars.
Accurate Specialties offers a full range of casting processes to ensure the production of high-quality gear blanks for a variety of applications.