What is the difference between quarter turn actuators type COPAR (DRD/DRE) and type SYPAR (DAPS)?
The quarter turn actuator SYPAR (Scotch-Yoke-Pneumatic-Actuator-Rotative) is based on the second most important operating principle for quarter turn actuators in the process industry, the Scotch yoke principle. Whereas the COPAR has linear torque characteristics due to its rack & pinion principle, the torque curve for the SYPAR is non-linear. This property is produced by the lever arm moving through the entire swivel angle (0°-90°). Accordingly, with the design of a SYPAR actuator special attention must be paid to three factors. These behave as follows: 0° initial breakaway torque, maximum rotational torque Mmax = 100% 45° Minimum rotational torque Mmin = 0.5 x Mmax 90° Torque at the end positions Mend = 0.75 x Mmax The way the torque output varies is thus the most important difference between these two actuators.
