Nutrunners

Nutrunners are built for accurate torque control, by delivering smooth and consistent torque to a fastener. This makes them ideal for applications where bolts must be tightened to exact specifications, which is why nutrunners are used when the goal is repeatability, such as in the automotive assembly and aerospace manufacturing sectors.

An impact wrench on the other hand is designed to output high torque and speed. It uses a hammering mechanism to deliver bursts of force, making it excellent for loosening stubborn bolts or quickly tightening fasteners, however, this action is less precise than what is delivered by a nutrunner, which is why it is not suitable where exact torque control is critical.

Yes, a nutrunner can be used to both tighten and loosen a fastener, although it is most effective at tightening. This is because it is designed to apply precise and controlled torque to fasteners. If a fastener needs loosening and it is seized or tight, then a nutrunner wouldn't be suitable to loosen it because it doesn't provide the sudden force that is required, but as long as the fastener isn't too tight or seized, a nutrunner will be able to loosen it.

If the fastener is seized then we would recommend using an impact wrench or slogging spanner to loosen it, as both of these tools can apply vibrating and sudden energy to a fastener to loosen it more easily.

Yes a nutrunner can tighten fasteners to multiple torque values, however they perform best when tightening fasteners within their mid range, rather than at the very low end, or very high end of their torque scale, which can lead to reduced accuracy.

For example, a 10Nm - 50Nm nutrunner will not be as precise when tightening at 10Nm, as a 5Nm - 15Nm model would be.