Piston rod for hydraulic cylinder of packer

The invention provides a piston rod for a hydraulic cylinder of a packer. The piston rod comprises an end cap, a piston rod main body, a piston head and a sealing device, wherein the end cap is welded at one end of the piston rod main body; the piston rod main body serves as a steel pipe with a hollow structure; the piston head is connected with the piston rod main body through the sealing device. The piston rod for the hydraulic cylinder of the packer provided by the invention adopts the hollow structure, uses a force bearing point transfer method to improve the force bearing situation of the piston rod, and transfer most of the pressure subjected to the upper end of the piston rod to the lower end of the piston rod, so as to prolong the service life of the hydraulic cylinder, lower the stress of the piston rod, and solve the bending stability problem of the piston rod of the long-stroke hydraulic cylinder. Furthermore, the piston rod can save the material, lower the cost and lighten the weight.