Duplex filter for lubricating oil

The utility model discloses a duplex filter for lubricating oil. The duplex filter for the lubricating oil is good in filtering effect and convenient to use, and comprises a filter body; an oil inlet and an oil outlet are formed in the filter body, two filtering cavities are formed in the filter body, a top cover is arranged at the portion, above the filtering cavities, of the filter body, an annular installation boss is arranged on the inner wall of each filtering cavity, a detachable filtering element assembly is arranged on each installation boss, each filtering element assembly comprises an installation support and a plurality of candle type filtering elements arranged on the installation support in the circumferential direction, each candle type filtering element comprises an installation support body and a filtering net arranged outside the installation support body in a surrounding mode, an oil outlet through hole is formed in the top of a filtering net support, magnetic bars are inserted into the filtering net support from the oil outlet through holes in a penetrated mode, the filtering cavities are divided by the annular installation bosses and the upper portions of the installation supports into oil outlet cavities and the oil inlet cavities from top to bottom, the filter body is provided with two oil outlet channels communicated with the oil outlets and the oil outlet cavities and is provided with two oil inlet channels communicated with the oil inlets and the oil inlet cavities, and change-over valves for controlling opening and closing of the oil outlet channels and the oil inlet channels are arranged in the filter body.