Turning of Hard alloy External Circle Cutter Half Finish Turning
Hard alloys are materials that have a high work-hardening rate, meaning they harden under the stress of machining or grinding operations. For this reason, they are usually machined using tools that are specially suited to their exact requirements. One such tool is a hard alloy external circle cutter, which is often used in machining operations to create concentric or circular grooves or internal surfaces. Half finishing turning is a machining process often used with a hard alloy external circle cutter in which the cutter is moved parallel to the workpiece surface and fed to a predetermined depth and at a specific feed rate.
The selection of the proper feed rate for a cutting operation is critical for obtaining optimal results. Too high a feed rate can cause increased cutting forces that can cause deflection of the tool, resulting in poor surface finish and accuracy of the machined part. Too low a feed rate can cause excessive tool wear and a reduction in the life of the cutting tool. The feed rate for a half finish turning operation with a hard alloy external circle cutter is dependent on several factors such as the type of tool and cutting parameters, the material being cut, and the condition of the cutting tool. Generally, the feed rate should be set to achieve the desired cutting speed while minimizing tool wear.
A good starting point for determining the optimal feed rate for a hard alloy external circle cutter half finish turning operation is to determine the cutting speed for the material and cutting conditions. The cutting speed is a function of the cutting speed ratio and is expressed in surface feet per minute (SFM); it is determined by dividing the cutting speed ratio into the tool diameter. The cutting speed ratio is the ratio of the feed rate (in inches per revolution) to the radial depth of the cut (in thousandths of an inch). Once the cutting speed has been determined, the proper feed rate can be calculated based on the cutting speed and the spindle speed.
For this process, the feed rate should also be kept at a level which maintains consistent cutting forces. As with any machining operation, excessive cutting forces can cause the tool to deflect, resulting in a poor surface finish and accuracy on the finished part. Additionally, the feed rate should be increased at the beginning of the cut and then reduced over time to reduce tool wear.
The feed rate selection for a hard alloy external circle cutter half finish turning operation greatly affects the machining results. The cutting speed ratio should be selected first, and the feed rate should then be determined based on the cutting speed and the spindle speed. Appropriate feed rates should be set to achieve the desired cutting speed while minimizing tool wear. Lastly, the feed rate should be adjusted at the start of the cut and over the course of the cut to maintain consistent cutting forces and reduce tool wear. Following these guidelines will ensure optimal results for hard alloy external circle cutter half finish turning operations.
