Hydraulic oil cylinder piston rod mechanism

The utility model provides a hydraulic oil cylinder piston rod mechanism comprising a piston rod. One end of the piston rod is provided with a piston; the other end of the piston rod is fixedly connected with a lug; the piston rod is welded with the lug via friction welding; one end of a connection part between the piston rod and the lug is provided with an annular groove; and the distance between the annular groove and the end part of the piston rod is 1 to 2mm.The annular groove is arranged on one end of the connection part between the piston rod and the lug; the distance between the annular groove and the end part of the piston rod is 1 to 2mm; the depth of the annular groove is 2 to 4mm; part of fluid can flow toward the annular groove during high temperature welding and lug and piston rod combination strength can be enhanced; break of the connection is prevented; the connection looks beautiful; and welding wires are unnecessary during the welding, so cost is reduced.