Samson 3271 Original Instructions Manual

Also see for 3271: Mounting and operating instructions Mounting and operating instructions Mounting and operating instructions Mounting and operating instructions Mounting and operating instructions

Contents

6-4 EB 8310-6 ENStart-up6.1.3 Adapting the travelrangeIn some cases, the valve and actuator havedifferent rated travels. Depending on the di-rection of action, proceed as follows:Direction of action: actuator stem extendsAlways use actuators with preloaded springswhen the valve's rated travel is smaller thanthe rated travel of the actuator.Example: DN 50 valve with 15 mm ratedtravel and 700 cm² actuator with 30 mm rat-ed travel; 0.4 to 2 bar bench range.The signal pressure for half the actuator trav-el (15 mm) is 1.2 bar. Adding it to the lowersignal pressure range value of 0.4 bar re-sults in a signal pressure of 1.6 bar requiredfor spring compression. The new lower sig-nal range value is 1.6 bar and the new up-per signal range value 2.4 bar.Î Write the new signal pressure range of1.6 to 2.4 bar on the actuator nameplateas the operating range with preloadedsprings.Direction of action: actuator stem retractsThe springs of actuators with "stem retracts"action cannot be preloaded. When a SAM-SON valve is combined with an oversizedactuator (e.g. the rated travel of the actuatoris larger than the rated travel of the valve),only the first half of the actuator's benchrange can be used.Example: DN 50 valve with 15 mm ratedtravel and 700 cm² actuator with 30 mm rat-ed travel; 0.2 to 1 bar bench range.At half the valve travel, the operating rangeis between 0.2 and 0.6 bar.6.2 Travel stopRefer to Fig. 6-2In the version with travel stop, the maximumand minimum actuator travel can be limitedas follows:Direction of ac-tionMin. stop Max. stopStem extends (FA) 0 to 125 % 50 to 125 %Stem retracts (FE) 0 to 100 % 50 to 100 %6.2.1 Bottom travel stop(minimum travel)1. Loosen top lock nut (A74) and unscrewcover (A73).2. Loosen bottom lock nut (A74) and turnthe adjustment nut (A70) to adjust thetravel stop.3. Tighten bottom lock nut (A74).4. Attach the cover (A73) and retighten thelock nut (A74).6.2.2 Top travel stop (maximumtravel)1. Loosen top lock nut (A74).2. Adjust the cover (A73) to the requiredtravel stop.3. Retighten top lock nut (A74).