申请人:Nippon Oil Corporation
公开号:EP1908816A1
公开(公告)日:2008-04-09
The object of the present invention is to provide a base oil for hydraulic oil suitably used for hydraulic systems having filters of which micropore diameter is 50µm or less, which is capable to improve the decrease of flow in a hydraulic pump at low temperature like -30°C or less and capable to normally operate the hydraulic systems. The invention also provides a hydraulic oil composition using the above base oil, especially a hydraulic oil composition suitably used for such as tractors, transmissions, and common systems thereof having the hydraulic systems. In order to achieve the object, provided is a base oil for hydraulic oil comprising mineral oil, wherein the mineral oil is defined by kinematic viscosity at 100°C: 1.5~6mm2/s, pour-point: -10°C or less, viscosity index: 100 or more, %CP: 70 or more, %CA: 2 or less, and aniline point: 106°C or more; and wherein, the mineral base oil is treated by catalytic dewaxing process and/or contains tertiary carbon atoms at a ratio of 7.4% or more to the total carbon atoms.
本发明的目的是提供一种用于液压系统的液压油基础油,该液压油适用于具有微孔直径为 50µm 或更小的过滤器的液压系统,能够改善液压泵在低温(如 -30°C 或更低)条件下流量的减少,并能够正常操作液压系统。本发明还提供了一种使用上述基础油的液压油组合物,特别是一种适用于拖拉机、变速箱及其具有液压系统的普通系统的液压油组合物。为了实现上述目的,本发明提供了一种由矿物油组成的液压油基础油,其中矿物油在 100°C 时的运动粘度为 1.5~6mm2/s:1.5~6mm2/s,倾点:-10°C 或更低,粘度指数:100 或更高,%CP:70 或更低:其中,矿物基础油经过催化脱蜡工艺处理,和/或含有占碳原子总数 7.4% 或以上比例的三级碳原子。