I have a problem with 9.52 diameter aluminum coils, EC Grade, used in wire drawing for our Power Cables Division. They arrive from the supplier in wet condition (Because of rainy season and poor packaging) and tend to break at the first die. We suspect the water particles/ moisture present on the surface or oxidized patches are starving the oil coolant at the die interface. We have tried heating the coil in a furnace with some positive result. But the electricity cost is more. I need some solution for removing water from the surface effectively so that it is drawn without problems. Altogether if problem continues, whether it will affect the quality of conductor? Increase Conductor Resistance ...or .. tensile value ..or something.. Can somebody help.
Aluminum drawing oils and water do not mix and water on the rod will certainly break the rod at the entry die. It will also contaminate the drawing oil in the reservoir tank and this will lead to more wire breaks.
Whatever you do to eliminate the water (compressed clean and dry air, propane surface heater or electrical heater) is going to cost your division money.
I suggest you charge back the cost of drying the rod to your supplier and then watch how quickly the problem is resolved. In this case, you are clearly your own quality control. If you accept wet coils, then that is the standard.
Peter J. Stewart-Hay
Stewart-Hay Associates www.Stewart-Hay.com
519 641- 3212