Title: ROD WELDING PROCEDURE
Applications: Particularly for 5.0 mm rod on HP5 using the E.H. Welder but also generally applicable with necessary heat setting adjustments on other rod sizes / welders.
1. Rod End Preparation
1.1 Straighten 18” lengths both rod ends
1.2 Cut ends with disc cutter. N.B. Burrs will form if end is unsupported. Ensure ends to be welded (not offcuts) are held in vice jaws.
1.3 Allow slack for jaw movements when welding.
1.4 Remove burrs formed with grinding wheel (light action only required)
1.5 Remove surface scale, 3” – 4” each side, using emery cloth (not the grinding wheel).
2.1 Use heat setting 5.
2.2 Use maximum upset pressing setting (full upward clockwise turn of wheel)
2.3 Ensure rod is firmly and centrally located in jaws (ensure rods are well aligned / no slippage).
2.4 Use maximum upset traverse (travel). Ensure smooth movement.
2.5 Check that uniform petals are formed on weld.
3.1 Transfer sample to anneal jaws form weld jaws rapidly to maintain heat in centre (avoid bending the weld at this stage).
3.2 Use heat settings 3 and 4.
3.3 Hold for 30 – 40 seconds once ca 850C temperature is reached. Maintain constant temperature and use a watch to check time. (Aim for normal OHT quench temperature colour).
3.4 Allow to cool in jaws.
4.1 Remove flash with grinding wheel. Only touch the flash with the grinding wheel. Remove any transverse scratch / marks.
4.2 Finish with a medium file. Remove any transverse scratches / marks.
4.3 Finally rub down to a smooth surface with emery paper along the rod. Check the weld carefully for any obvious cracks, pits, transverse marks. Etc. Repeat weld if surface finish is sub-standard.
4.4 Soap the weld.
4.5 Lacquer either side of the weld and allow 5 – 10 minutes drying time before drawing.