Configurator

Each shut-off valve has a specific breakaway torque without load for opening and closing this valve. This depends on the technical characteristics of the valve (nominal size, seal, design, etc.) and is usually specified by the manufacturer.
This torque must be overcome with the aid of an electric or pneumatic actuator in order to move the valve to its respective end positions.
Depending on the application and operating conditions, the specific torque may increase under load. The medium and pressure as well as the downtime of the valve have an influence.
To ensure safe opening and closing of a valve under load, the specific valve torque should not only be overcome minimally, but exceeded by a defined factor. In actuator technology, the design therefore takes the so-called safety factor into account. For applications with adhesive, non-lubricating media, higher operating pressures or long service lives, a higher safety factor should be used. Non-adhesive, lubricating media, low pressures and/or high switching frequencies require correspondingly smaller safety factors.
For pneumatic actuators, it should also be noted: A higher safety factor accelerates the closing and opening of the valve.

Without input, the differential pressure automatically corresponds to the operating pressure.
The differential pressure is the result of the inlet pressure upstream of the valve minus the outlet pressure downstream of the valve.
If the valve is shut off against free outlet, a differential pressure equal to the operating pressure results. This means that the shut-off element in the valve (ball/disc) is pressed into its seat by the force of the full operating pressure.
Counter pressures (and thus smaller differential pressures) can ensure that the friction in the shut-off element of the valve is lower and thus a lower torque is required and thus have an influence on the actuator design.