October 18, 2012 - Flowserve release the NAF Duball DL ball valve featuring spring-loaded packing technology. A Z-trim option improves control behavior, providing high rangeability, and provides anti-cavitation functionality and noise attenuation. A NAF Turnex pneumatic actuator can be mounted on the ball valve and offers an ideal high-performing, vibration-resistant compact valve package providing economical total cost of ownership. The design incorporates spring-loaded stem packing technology on ANSI class 150 and 300 versions covering applications up to 250 degrees Celsius/482 degrees Fahrenheit. The NAF Duball product family has a split body with floating ball design providing excellent leak tightness.
The valve's ball and seat are designed to be easily serviced without removing the valve stem and actuator. The NAF Duball DL ball valve can be used in automated on/off applications and is equally suitable for a wide range of control applications. The ball valve's spring-loaded packing remains tight for a higher number of cycles, virtually eliminating the need for manual retightening of the packing. The mechanical backlash is minimized by the uniquely designed long connection between the ball and stem which is especially important in control applications.