In order to improve the extraction efficiency of the oil information related to the running status of the equipment, a new analytical technique called oil filtergraphy technology is proposed in this paper. A further discuss is made of its main content, implementation process and engineering significance. Firstly, the filtergram is prepared based on the filtergraphy, then the image segmentation technology, automatic counting algorithm and fuzzy support vector machine are used to realize the automation of analysis process. The intelligent extraction of oil information is completed and the key information reflecting the running state of the equipment is obtained at the same time. Applying the technology to the condition monitoring of rotary drilling rig equipment, the lubricant state and wear condition for the current stage are assessed after analyzing the suspended particles from hydraulic oil and gear oil. According to the results of qualitative and quantitative analysis, some useful guidance is provided for its repair and maintenance. It is indicated that oil filtergraphy technology can extract the complete information contained in the oil to reflect the running status of the equipment. It has the advantage of high detection efficient and abundant analysis content, and can be extended to other equipment for oil monitoring and fault diagnosis.