Rotary & Inertia Friction Welding (RFW) Upset & Flash Calculator
Engineering calculator for rotary friction welding (RFW) and inertia friction welding (IFW). Computes axial thrust, upset forging force, spindle RPM, total axial burn-off shortening allowance, and post-weld flash curl turning stock.
1. Input Parameters
2. Calculation Results
3. Geometric Visualizer
Tooling & Vector Prepress Engineering Notes
Solid-State Joining Kinematics: Rotary Friction Welding (RFW) joins metal interfaces below their melting point via frictional heat generated by rotating one component against a stationary counterpart under axial friction pressure ($P_{\text{fric}}$). Once plasticizing temperature is achieved, rotation stops rapidly (braking < 0.2s) and forging upset pressure ($P_{\text{upset}}$) is applied to expel surface oxides into the external flash curl.
Axial Burn-off Length Compensation: The total axial shortening ($\Delta L_{\text{total}} = \Delta L_{\text{fric}} + \Delta L_{\text{upset}}$) must be programmed directly into the pre-weld blank length CAD/CAM DXF geometries. For bimetallic welds (e.g. Inconel to alloy steel), asymmetric plastic flow occurs, requiring differential pre-weld allowance allocation.
Post-Weld CNC Flash Removal Toolpath: The extruded mushroom flash collar contains forged oxides and high residual stress. CNC turning profile vector toolpaths must incorporate a root fillet radius ($R \ge 1.5 \times \text{wall thickness}$) to eliminate sharp stress concentration notches.