Product Overview Solenoid Valves - BURKERT FLUID CONTROL SYSTEMS - #5

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table.main {} tr.row {} td.cell {} div.block {} div.paragraph {} .font0 { font:7.00pt "Arial", sans-serif; } .font1 { font:7.20pt "Arial", sans-serif; } .font2 { font:8.00pt "Arial", sans-serif; } .font3 { font:20.00pt "Arial", sans-serif; } .font4 { font:5.00pt "Verdana", sans-serif; } Burkert | Solenoid Valves Direct Acting Valve Anatomy Coil Wrapped enamelled copper coil which concentrâtes the effect of the magnetic field produced when current passes through a conductor. Available to employ alternating (AC) or direct current (DC). DC coils are quieter, show less wear on the plunger or core tube and demonstrate a high holding force whereas an AC coil, although it displays faster switch-ing times, can hum, requiring a shading ring and facing a risk of burn-out if the plunger is ever jammed. Air Gap and Stopper Stringent requirements in regards to evenness, flatness and peak-to-valley height are made on the pole faces of the stopper and plunger to achieve a hum-free holding force which is as high as possible. A large air gap between the poles substantially reduces the holding force since the mag-netic conductivity of air is substantially less than that of iron. Encapsulation Either polyamide or epoxy coating is molded around the coil to protect it from damage. The material determines the working rate of the coil. The encapsulation material and the coil surface area predict good heat dissipation and radiation from the surface. The chemically resistive encapsulation protects the electrical system against harmful influences such as dust, dirt and moisture. Retaining nut Electrical connection Core tube aaIaaa Stopper Encapsulation Coil A precision mass which reacts to the influence of the mag­netic field created by the coil when current is added. The plunger is held by the coil for as long as current flows. When the flow of electric current is halted the spring forces the plunger back to its rest position. Stringent magnetization properties, low magnetic memory effect, high wear resis­tance as well as high chemical resistance are required. Spring The spring usually works against the coil to revert the valve back to its normal position when the valve sees no power. Electrical Connection A wide range of global electrical connections are available. Many solenoid systems are designed for IP65 protection. Core tube Accurate tube in which the plunger moves. Shading ring (Required on AC Only) An electrically conductive ring located in the stopper to pre-vent constant oscillation based on the mains frequency. Without this addition noise would result from the interac­tion of the spring force and the magnetic force when, twice per cycle, the voltage drops to zero and the spring wins the contest. Shading ring - Air gap Spring Plunger Usually measured by diameter in mm this determines the area on which the media pressure will act and the gap through which the media will flow when the valve is ener-gized. Burkert deliver valves with orifice diameters from 0.05 mm to 65 mm. Fluidic Connection Many fluidic sizes and connections are available to meet local geographic or industry specific standards. Seal & Seat A seal is the soft material, connected permanently to the plunger, which halts the flow of fluid from one side of the orifice to the other when sitting on the seat which is a raised area on the orifice which concentrates the pressure of the seal. Seal Seat Orifice Inlet Fluidic connection Outlet Direction of operation Solenoid valves are the most frequently used control elements in fluidics. Their tasks are to shut off, release, dose, distribute or mix fluids (liquids and gases). They are confronted with many different requirements in a plethora of application environments and must offer: - fast and safe switching - high reliability - long service life - good medium compatibility of the materials used - low control power - compact design