Patent ID: 8171988

Claim:
A stroker tool for providing an axial force in an axial direction of a downhole tool, comprising: a pump, a driving unit for driving the pump, and an axial force generator comprising: an elongated piston housing having a first and a second end, and a piston provided on a shaft, the shaft penetrating the housing for transmitting the axial force to another tool, wherein the piston is provided in the piston housing so that the shaft penetrates the piston and each end of the piston housing and divides the housing into a first and a second chamber, and wherein the first chamber is fluidly connected to the pump via a duct and the second chamber is fluidly connected to the pump via another duct so that the pump can pump fluid into one chamber by sucking fluid from the other chamber for moving the piston within the housing, and thereby moving the shaft back and forth.