A straight shank double-layer drill, also commonly known as a straight shank step drill or a two-stage step drill, is a drilling tool with a special design. The following is a detailed explanation of a straight shank double-layer drill:

Definition and Structure

A straight shank double-layer drill is a drill with a straight shank and a double-layer stepped cutting portion. It is designed to complete the processing of holes of different diameters in one drilling operation, thereby simplifying the drilling process and improving work efficiency. This drill usually consists of a shank, a neck and a cutting portion. The shank is a straight shank, which is used to connect with the machine tool to play a role in centering and transmitting power.

Working Principle

During the drilling process, the straight shank double-layer drill uses its double-layer stepped cutting portion to gradually expand the hole diameter. As the drill rotates and feeds, the cutting portion gradually cuts into the workpiece to form the desired hole diameter. Since the cutting portion is stepped, multiple diameter holes can be processed in one drilling operation.

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