The study presents the possibility to measure the torque and axial force of the working system of the screw compactor machine with open working chamber. Attention was drawn to the relationship between the two parameters and the geometric properties of the working system and the thermomechanical properties of the compacted materials. A functional construction coefficient was proposed and defined to bound together the value of torque and axial force. Its usability was demonstrated for identifying the parameters of compaction process together with its applicability for controlling these types of processes.