PURPOSE: To prevent generation of a pipe having deviated wall thickness, by providing a desired number of load detectors which transduce a load into an electric signal in the vicinity of the supporting end of a stem for an extrusion press, and controlling cylinders by the transduced signals so as to eliminate the unbalance of loads acting on the stem with the said of a controlling device.

CONSTITUTION: When an extrusion press is actuated, moment M1 in extrusion process and moment M2 in punching process are produced, in making a container 12 follow the movement of a counter platen 10 up because of an existance of frictional force in a sliding surface, to move the container 12 slantly, and then both of unbalancec compressive load and bending moment act on the stem 4. Both of the unbalanced load and moment are detected by a detector 28, through e.g. two strain gauges 26 provided to the end part of the stem 4, to be inputted to a controller 32 after transducing the detected results into electric signals by an operator 29. The controller 32 actuates cylinders 16 through servovalves 31 to correct the position of a main cross head so as to make the load distribution uniform.