Method to control a butterfly valve

摘要

The procedure, for use on a butterfly valve (4) opened and closed by a control system comprising an electric motor (6), servomotor (7) and reduction gear (8), consists of first disengaging the control system and measuring at least the starting force of the servomotor and the output force of the reduction gear when the servomotor is actuated at various angular positions of the valve. In a second phase the valve is moved between closed and open positions by the electric motor through the control system, measuring the active power of the motor and calculating the output force of the servomotor and/or reduction gear, and the values obtained are compared with those obtained during the first phase.