Collins Instrument Company’s line of economical 2-inch flanged plastic control valves handle corrosive liquids — including hydrochloric acid, caustic, sulfuric acid, and many others. With bodies of either PVDF or polypropylene, these control valves are specifically designed for use with corrosive media and/or corrosive atmospheres.
Suitable for chemical handling, these valves are extremely corrosion-resistant, feature fast-acting positioning, and are available in a wide selection of trim sizes.
The specialized control valves stroke at the rate of approximately half an inch per second. Their differential area piston eliminates the necessity for auxiliary loading regulators, and the actuator is molded of glass-filled, UV-inhibited polypropylene except for the integral positioner.
Before shipment, the aluminum positioner and a portion of the cylinder are immersed in dip seal to provide atmospheric protection. The integral positioner eliminates the need for external linkages which are subject to corrosion and malfunctioning.
The control valves are available in globe, angle, or corner configurations to fit the appropriate piping. The valves may also be furnished without the positioner for ON - OFF applications.
Collins valves incorporate a unique closure between the cylinder and yoke, eliminating the previous threaded closure. The actuator is attached to the yoke with an internal locking ring, which is inserted through a slot in the side of the actual cylinder. This is accomplished by machining a half circle grove inside the lower edge of the cylinder and matching half circle groove in the yoke. When the yoke and cylinder are assembled, a 5/32-inch OD polypropylene rod is inserted through the slotted hole into the groove, locking the two together.
In addition to the valves, Collins also offers a plastic, pneumatic actuator. When assembled with one of the Collins plastic valve bodies, the resulting combination represents an effective way to handle both corrosive materials that flow through the valve as well as the harsh environments that can attack the outside of the valve and actuator. The plastic control valve package can therefore withstand the salty atmosphere of coastal areas as well as the corrosive environments which are too volatile for metal actuators used with other control valves.
Along with its corrosion resistance, the Collins control valve features a stem packing arrangement that virtually eliminates the problem of fugitive emissions, thereby protecting the environment. WW
Collins Instrument Company has been serving the chemical and petrochemical industry for over 65 years. To learn more, visit www.collinsinst.com.