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AWWA C507-15 pdf download.Ball Valves, 6 In. Through 60 In. (150 mm Through 1,500 mm)
4.3.10.5.2 Proof of design. Te actuator mechanism between the cylin- der and the valve shaft shall meet the requirements of Sec. 4.3.10, including the proof-of-design requirements of Section 5.2.3, except the input testing require- ments of Sec. 5.2.3.3 shall not apply.
4.3.10.5.3 Stroke time adjustment. Opening and closing times shall be feld adjustable. Cylinders shall be equipped with adjustable fow-control devices to control the operating media exhausted from the cylinder unless equipped with a posi- tioner that also functions as a fow-control device. Adjustable fow-control devices are optional for use with a positioner but must be specifed by the purchaser.
4.3.10.5.4 Air service fow controls. For air service, the fow-control devices shall be mounted directly on the cylinder or connected within 6 in. (152 mm) of the cylinder by rigid metal pipe or rigid metal tubing unless otherwise specifed.
4.3.10.5.5 Stroke time. Unless otherwise required in the purchase docu- ments, pneumatic or hydraulic actuated valves shall be designed to operate from the fully open to fully closed positions, or the reverse, based on an adjustable range of the greater of 10 sec (±20 percent) or 2 to 4 sec/in. nominal valve size at the minimum supply pressure. Te supplier shall document the design stroke time range. Te stroke time of actuators provided without feld-adjustable control valves will vary based on the installation and pressure supply.
4.3.10.6.1 Actuator extensions. Quarter-turn extensions between the actuator and the valve shaft used to transmit torque shall meet the requirements of Section 4.3.10.1 except for proof-of-design requirements of Section 5.2.3. Te total torsional defection at seating shall be less than ¾° or shall have an adjustable stop-limiting device at the connection to the valve. If a stop-limiting device is used, the total torsional defection shall not exceed the actuator’s over-travel adjustment capability. Te total torsional defection of the extension during midstroke opera- tion shall be less than 5°.
4.3.10.6.2 Electric actuator extensions. Extensions between the electric actuator and a fnal drive gear used to locate the electric actuator at a distance from the fnal drive gear shall meet the requirements of Sec. 4.3.10.1 except for proof-of- design requirements of Section 5.2.3. Te total torsional defection of the extension during operation at the actuator sizing torque (MRST) shall also be limited to less than 5°.AWWA C507-15 pdf download.