2017 Volume 103 Issue 3 Pages 134-141
Cold sheet gauge rolling in a tandem mill is used to produce many types of steel, including automotive and high-strength steel sheet.
A recirculating oil in water emulsion is used as a lubricant between the roll and material in sheet gauge rolling. With an increase in steel sheet production and the ratio of high-strength steel sheets, the amount of fine iron particles produced by the rolling process also increases. Thus, maintaining the cleanliness of the mill and sheet is difficult when using conventional rolling oil with a non-ionic emulsifier, as dispersion of fine iron particles is not enough efficient.
Therefore, a rolling oil is developed by adding a cationic emulsifier to a conventional rolling oil used for sheet gauge rolling. As a positive charge is produced on the surface of the newly developed oil, it can easily disperse fine iron particles that would otherwise adversely affect the cleanliness of both the mill and sheet.
In this study, the newly developed oil was compared with conventional oil with a non-ionic emulsifier in a laboratory to verify its performance. The following findings were then applied to an actual mill.
The oil developed for sheet gauge production was used in an actual mill to maintain stable emulsion to ensure a high level of productivity without friction pick-up.
Fine iron particles that are inevitably produced owing to the rolling process were effectively removed. The newly developed oil is superior to conventional oil in terms of maintaining the cleanliness of the mill and steel sheet.