Pneumatic Valves and More

Pneumatic systems rely on valves and other components for proper operation. For valves, beyond the flow rate and pressure limits, additional requirements could include mounting considerations, the need for pressure compensation for flow, response time and port design. Special applications require even greater attention to valve specifications and additional hardware support. Manifolds that accept a variety of valves simplify the configuration of more complex systems. Applications with oxygen require unique valve design and manufacturing considerations. Compliance with work environment standards may dictate the use of a reclassifying muffler. This section shows how four valves, a manifold and a muffler handle a variety of system requirements.

FLOW CONTROL VALVE

Beswick Engineering's PCFCD-1N1 is an ultra-miniature, pressure-compensated flow control valve with a low-friction diaphragm. The small valve weighs only 48 gm and controls flow rates of 0 to 4.2 gph of water (0 to 20 cubic ft3/hr of air). A customer-adjustable flow rate is maintained in spite of upstream or downstream pressure variations. A low-friction diaphragm mechanism regulates the pressure. Primarily intended for controlling liquids, the valve works with both liquids (incompressible fluids) and gases (compressible fluids). The valve has a brass body with a standard Buna-N or optional Fluorocarbon (Viton) seal material. Designed for the control of low flow rates, the maximum rated inlet supply pressure is 500 psig. The small and lightweight unit can be mounted in-line without the need for a panel mount thread.

PROPORTIONAL CONTROL VALVE

Humphrey Products Co. KFPV050 valves provide stepless variable control of gases and liquids. The body of the direct acting 2-port plunger is either brass or stainless steel. For flexible orientation, the solenoid has 360-degree mounting and its elbow electrical terminal can be positioned every 90-degrees from top to bottom and left to right. Designed for use with the company's KFPC1 Controller, on-board circuits support initial settings without any external input. A zero point switch-off function on the controller ensures all valves are completely closed and LEDs indicate the status. Current settings for initial valve opening and valve fully open are adjusted by two potentiometers.

VALVE MANIFOLD

Festo VTSA/VTSA-F valve manifolds provide flexibility and modularity for valves and electrical connectivity. The valve system uses plug-in sub-base-style valves. Conforming to applicable ISO standards, the VTSA Type 44 valve manifold allows the combination of Sizes 01 (18 mm), 02 (26 mm) and Size 1 (42 mm) valves without the need for any transition/adapter plate. The three valves provide a flow range of 500 to 1,500 l/min. For higher flow rates, the VTSA-F Type 45 manifold, a non-standard sub-base, offers an increased flow rate of up 700 l/min for the Size 01 (18 mm) and 1,400 l/min for Size 02 (26 mm) valve. With the choice of a range of 3- and 5-way valves, the manifold allows mounting of 16 valves and 32 coils. Electrical connection options include terminal box, M12, multi-pin and Fieldbus. The valves target applications in automotive and tool manufacturing, printing, paper and packaging machinery, robotic peripherals and more.

OXYGEN CLEAN VALVES

Designed for use with oxygen applications, Clippard Instrument Lab. Inc. O-E Series pneumatic valves work with air and inert gas, too. The 2- or 3-way, normally closed or fully ported valves have a response time of 5 to 10 msec, power consumption of 0.67W and operate from voltages of 6, 12 or 24V dc. While the standard pressure range is 28-inch Hg vacuum to 105 psig with 7 bar max, the L option allows 28-inch Hg vacuum to 50 psig with 3.5 bar max and the H option ranges from 28-inch Hg vacuum to 25 psig with 1.8 bar max. Corresponding standard air flow is 0.6 scfm at 100 psig and 17 l/min at 7 bar with the L option providing 0.5 scfm at 50 psig and 14 l/min at 3.5 bar and the H option delivering 0.45 scfm at 25 psig and 13 l/min at 1.8 bar. Any organic or inorganic contaminants, such as particulate matter and hydrocarbon oils, are removed by ultrasonic cleaning at the end of the assembly process in an enclosed controlled area with a positive pressure High Efficiency Particulate Air (HEPA) filtration system.