Lubricator for conveying cylinder of concrete pump

The utility model relates to a lubricator for conveying cylinder of concrete pump, a cavity and an oil conveying plunger which is withstood by a spring are arranged in the plunger connecting pole. A concave pit is arranged in the plunger body, and the cavity and the concave pit are separated by a lid board fixed on a flange. Damp holes are arranged on the lid board, an oil transmitting hole which is arranged in the connecting pole is communicated with the cavity, and an oil outlet in the plunger body is communicated with the concave pit and the external circle of the plunger. The utility model arranges a lubricating device in the internal of the plunger, the need to open a hole vertically on the conveying cylinder is eliminated, and the problem of conveying cylinder scraping brought by the traditional lubricating manner is conquered.