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Control systems Pneumatic actuators
How to use the sizing data: The following tables supply guidance as to the sizing of the TN2000 when it is used on the SPIRA-TROL series control valves. There are three applications: Unbalanced flow under applications Unbalanced on/off flow over applications Balanced flow under applications
Two conditions are illustrated in tabular form in each of the applications: Class IV shut-off - Providing shut-off of the valve to the requirements of EN 60534-4 (IEC 60534-4) Class IV. Class VI shut-off - Providing shut-off of the valve to the requirements of EN 60534-4 (IEC 60534-4) Class VI. Class V shut-off - Providing shut-off of the valve to the requirements of EN 60534-4 (IEC 60534-4) Class V.
To select a suitable actuator: - Identify the column containing the valve and gland material selected. - Identify and compare the maximum operating pressure condition, including any transient pressures likely to occur, within the selected column. Note: Flow over the plug for modulating control is not recommended. Flow over is only suitable for on/off applications. For conditions outside of those illustrated, including double acting versions, please contact Spirax Sarco. Note: For TN2277SR, the values in the following tables are based on the air pressure indicated below the product nomenclature of the specific unit. For double acting actuators in the event of air failure you will require an air pressurised tank to position the valve. For fluctuating pressure control applications, or applications requiring rapid response (e.g. accumulator control)a pneumatic volume booster is recommended.
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TI-P327-01 CTLS Issue 5
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TN2000 Series Pneumatic Piston Actuators for DN125 to DN300 SPIRA-TROL Series Control Valves
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