To control reduction in lubricant for maintaining the lubrication life time over a long period by the support with a roll bearing to which a lubricant is sealed under the specified pressure under the particular temperature.
As a lubricant, fluorine oil with vapor pressure of 1×10-3 torr. or less at 25°C, alkyl chain derivative polyphenyl ether oil, alkyl chain derivative naphthalene oil, paraffin-based hydrocarbonate oil or the like are used. The lubricant is supplied directly into the roll bearing or supplied as a lubricant grease, after mixing of adequate expanding agent. As an expanding agent, a urea compound having suitable heat resistance property, in addition to a metallic soap or the like, can be used. As a result, long-term lubrication can be realized with a small amount of lubricant.
YOKOUCHI ATSUSHI
NAKA MICHIHARU
