gen-define-machining-feed-and-speed-rates-and-give-one-short-wor-3bbe

Define machining feed and speed rates and give one short worked example.

# Machining Feed and Speed Rates ## Definitions **Speed Rate (Cutting Speed)** - The surface speed at which the cutting tool moves relative to the workpiece - Measured in: meters/minute (m/min) or feet/minute (ft/min) - Formula: **V = π × D × N / 1000** (metric) - V = cutting speed (m/min) - D = diameter of workpiece or tool (mm) - N = spindle speed (RPM) **Feed Rate** - The distance the cutting tool advances per revolution or per minute - Measured in: mm/rev, mm/tooth, or mm/min - Formula: **F = N × f** - F = feed rate (mm/min) - N = spindle speed (RPM) - f = feed per revolution (mm/rev) ## Worked Example **Problem:** Calculate the spindle speed and feed rate for turning a 50mm diameter steel shaft with: - Recommended cutting speed: 90 m/min - Feed per revolution: 0.25 mm/rev **Solution:** 1. **Spindle Speed (N):** - N = (V × 1000) / (π × D) - N = (90 × 1000) / (π × 50) - N = 90,000 / 157 - **N = 573 RPM** 2. **Feed Rate (F):** - F = N × f - F = 573 × 0.25 - **F = 143 mm/min**