Search results
Results from the WOW.Com Content Network
Cutting speed may be defined as the rate at the workpiece surface, irrespective of the machining operation used. A cutting speed for mild steel of 100 ft/min is the same whether it is the speed of the cutter passing over the workpiece, such as in a turning operation, or the speed of the cutter moving past a workpiece, such as in a milling operation.
Hard turning is a type of turning done on materials with a Rockwell C hardness greater than 45. It is typically performed after the workpiece is heat treated. [3] The process is intended to replace or limit traditional grinding operations. Hard turning, when applied for purely stock removal purposes, competes favorably with rough grinding.
Finishing operations are carried out at low feeds and depths – dinners of 0.0125–0.04 mm/rev (0.0005–0.0015 in/rev) and depths of 0.75–2.0 mm (0.030–0.075 in) are typical. [9] Cutting speeds are lower in roughing than in finishing. A cutting fluid is often applied to the machining operation to cool and lubricate the cutting tool ...
The speed at which the piece advances through the cutter is called feed rate, or just feed; it is most often measured as distance per time (inches per minute [in/min or ipm] or millimeters per minute [mm/min]), although distance per revolution or per cutter tooth are also sometimes used. There are two major classes of milling process:
It relates to spindle speed via variables such as cutter diameter (for rotating cutters) or workpiece diameter (for lathe work). SFM is a combination of diameter and the velocity ( RPM ) of the material measured in feet-per-minute as the spindle of a milling machine or lathe . 1 SFM equals 0.00508 surface meter per second (meter per second, or ...
Programmers are usually machinist as well. A CNC programmer creates programs using software called CAM (computer aided manufacturing). The programmer must be proficient in math, speeds and feeds, machine tooling, work holding, and the different ways various materials react to stress and heat in the machining process.
A machinist calculator is a hand-held calculator programmed with built-in formulas making it easy and quick for machinists to establish speeds, feeds and time without guesswork or conversion charts. Formulas may include revolutions per minute (RPM), surface feet per minute (SFM), inches per minute (IPM), feed per tooth (FPT). A cut time (CT ...
Factors that affect the quality and effectiveness of facing operations on the mill are speeds and feeds, material hardness, cutter size, and how the part is being clamped down. [3] Spotfacing is the facing of spots (localized areas), such as the bearing surfaces on which bolt heads or washers will sit.