Grinding is a process that produces very accurate dimensions and fine finishes. This machining process can be used to rapidly remove large volumes of metals but is primarily used to remove small amounts to achieve fine finishes and tolerances greater than .001”. Double Eagle Alloys offers two types of grinding services, in addition to lathe turning.

Centerless Grinding: Centerless Grinding is a machining process in which abrasive cutting is used to remove material from a workpiece. In this process, the piece is supported by a workblade that is set between a regulating wheel and a high-speed grinding wheel with a larger diameter. Because the workblade is sloped, the piece is above the center of the wheels. This allows for accuracy without a center cut. Simple but precise, centerless grinding is a great process for high-volume applications because of its ability to perform consistently at high speeds.

Grinding Between Centers: In this process, the piece is braced on each end by centers or sometimes placed on a magnetic chuck. The turning process creates the centers on the ends of the parts and precision center points position and hold the workpiece at the geometric true center, moving it in a rotational direction and allowing for the grinding action. This process produces the most accurate of all grinding techniques by forming the outside of the piece to tight tolerances.

Lathe Turning: Lathe turning is a pre-grinding process where the diameter of the piece is reduced by turning a bar horizontally while a stationary tool bit cuts into the piece. This results in a smooth finish and allows for custom shapes. In some cases, precision turning with specialized tooling, such as burnishing or wiper insert geometry, can achieve grind tolerances at a fraction of the cost. Lathe turning can remove large amounts of excess material leaving minimal material for center grinding

Key Terms:
Turned Ground and Polished (TG&P) – This is a finishing process that creates extremely straight round bars by turning, while extreme accuracy is achieved by grinding and polishing.

Boat Shaft Quality (BSQ) – In this type of shafting, straightness of the bar is key to preventing wobble and misalignment issues that can significantly reduce shaft life. There are tolerances and finishes required to meet BSQ standards.

Pump Shaft Quality (PSQ) – This type of shafting is used primarily in rotating industries. Tight diametrical tolerance requirements and straightness give minimal vibration and decrease wear.

Bearing Quality (BQ) – This bar doesn’t have requirements regarding straightness, length, or finish, but has custom diametrical tolerances.

Double Eagle Alloys provides high-quality and accurate grinding capabilities to meet your close tolerance requirements. Contact one of our experts today for more information.