The surface irregularities of electrodes used in an electrochemical machining (ECM) process are 3 μm and 6 μm as shown in the figure. If the work-piece is of pure iron and 12V DC is applied between the electrodes, the largest feed rate is mm/min. Conductivity of the 0.02 ohm–1 mm–1 electrolyte Over-potential voltage 1.5 V Density of iron 7860 kg/m3 Atomic weight of iron 55.85 gm Assume the iron to be dissolved as Fe+2 and the Faraday constant to be 96500 Coulomb.
Requirement in the design of jigs and fixtures P. Heavy clamping force on the workpiece Q. Clamping on rough surfaces of workpiece R. Four workpieces in a line to be machined in one loading S. Drilling and reaming of workpiece in one loading Recommended device 1. Clamp wlth a floating pad 2. Slip renewable bush 3. Indexing bush 4. Equalizing clamp 5. Strap clamp
Match the following Process A. Explosive welding B. Brazing C. Thermit welding D. Manual metal arc welding Associated Mechanism 1. Liquid state 2. Solid state 3. Solid liquid state 4. Liquid state Chemical