Flowserve Cast Globe Valves - Manual (Page 12)

Globe Valves FCD ADENIM0011-00
12
4.0 OPERATING THE VALVE
Prior to operating the valve for the first time, verify that the valve has been prepared in accordance with the preceding sections
of this manual.
4.1 Hand Actuated
Handwheel actuated valves close on clockwise rotation of the wheel and open counter-clockwise. This is true also for the
handwheel on gear and motor actuators.
4.2 Motor Actuated
4.2.1 The motor actuators on Anchor/Darling valves are adjusted for correct operation when shipped from our plant. It
should not be necessary to re-adjust the torque and limit switches when the valve is placed in operation unless the
actuator has been removed from the valve or the switch adjustments have been tampered with.
4.2.2 Adjustments of torque or limit switches should not be attempted without first consulting Anchor/Darling Service
Engineers. Failure to obtain proper authorization when resetting torque or limit switches may void the warranty.
Under no circumstances should the torque and/or limit switches be completely bypassed. They are included to
provide protection of the valve internals. Removal of their protection can cause extensive damage to the
equipment.
4.2.3 The valve is normally supplied with the torque switch wired to stop the operator in the closed position and the limit
switch wired to stop in the full open position. Using the torque switch to control travel in the opening direction may
damage the backseat. The valve should be backseated only by using the handwheel.
4.2.4 When powering the actuator for the first time observe that the direction of rotation is correct. If not, the power leads
must be reversed.
4.2.5 Manual operation may be performed at any time by pulling the declutch lever downward. The lever will stay in the
manual mode until the electric motor is actuated whereupon it will automatically disengage.
4.3 Throttling
Changing the position of the disc will vary the volume of fluid allowed to pass through the seat. Once the desired flow rate
is obtained the valve can be left unattended. Selflocking stem threads insure that the disc position will be maintained.
4.4 Isolating
When valves are closed and flow is over the disc, shut off should be obtained and maintained without adjustment. When
valves are closed with flow under the disc, sufficient force must be extended on handwheel or by the motor in order to
achieve a seal. If the valve is supplied with an impactor handwheel it may be necessary to use the impactor to get tight
shutoff. In addition, globe valves, shut off with flow under the disc, should be periodically checked to see that they are
sealing properly. If leakage is present, additional force must be applied to the stem to reseal the disc. With the disc in
the closed position the seat must not be allowed to leak for an extended period of time. Continuous seat leakage may
cause severe damage to the sealing surface.