Screw actuators are using probably in every production company. life of screw actuators have to be the logest as it possible. Engineers are working on their reliability. During the design process must be taken into account various factors such as fatigue, corrosion, excessive wear or dynamic and static loading. The most common failure of this type of screw is material fatigue. Cyclic compressive stresses cause wear elements cooperating with each other. The parameters of the various screws is different from one another and is not easy to replicate them in the laboratory. However, after years of work created norms that contain terms such as: fatigue life or nominal durability. In the case of Acme lead screw designation time is even more difficult because their construction contain elements from different materials such as bronze or plastic which wear non-linearly. This is the reason why manufacturers do not give life data of acme screws. There are many ways to determine the Screw Actuator Life and it have been save in International Standard ISO. The International Standard ISO provided a method of calculation and the steps what we need to take to choose properly a screw mechanism. Another solution is apply some safety ratio for calculating screw life values. Apply all of this parameters in calculation, allow to extend life of screw actuators.