Flowserve F519 Flanged ANSI - Manual (Page 6)

6 OPERATION
6.1 USE
Worcester ball valves provide bubble tight shut off when used in accordance with the published
pressure/temperature chart.
It is not good practice to leave a standard ball valve in the partially (throttled) position as this may
cause damage and seat life may be reduced. Flow control ball valves which contain seats designed for
this purpose are available from Flowserve Flow Control (UK) Ltd.
Any media which may solidify, crystallise or polymerise should not be allowed to stand in the ball cavity
since this is detrimental to valve performance and life.
6.2 MANUAL OPERATION
The basic type of wrench which is fitted is of sheet steel with integral stop.
Worcester valves have ¼ turn operation, closing in a clockwise direction. It is possible to see when the
valve is open or closed by the position of the wrench: When the wrench is in line with the pipeline, the
valve is open; when the wrench is across the pipeline, the valve is closed. Similarly, if the wrench is
removed the flats of the stem will also indicate valve position.
When operating the valve, the use of excessive side loading on the wrench should be avoided.
6.3 REMOTE OPERATION
Where automation of valves is required, Flowserve Flow Control (UK) Ltd. can supply pneumatic and
electric actuators to cover a wide range of operating torques.
Operation will be in accordance with installation, operation and maintenance instructions for the
relevant actuator.