For a control valve, this power source may be a solenoid, pressure pilot , or, if you have an electric actuator, an electric pilot. For further questions about solenoids or other oil and gas control equipment, contact your local Kimray store of authorized distributor. The Kimray Chronicle is your source for news within the Kimray community.
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Mega Menu Valves. Linear Electric. Rotary Electric. Linear Pneumatic. Drip Pots. Flow Meters. Flow Meter Accessories. Flow Monitors. Sense Line Protectors. Solenoid Valves. When the solenoid coil is energized in a normally open valve, the plunger seals off the orifice, which in turn prevents flow. In most flow control applications, it is necessary to start or stop the flow in the circuit to control the fluids in the system. An electronically operated solenoid valve is usually used for this purpose.
By being solenoid actuated, solenoid valves can be positioned in remote locations and may be conveniently controlled by simple electrical switches.
Solenoid valves are the most frequently used control elements in fluidics. They are commonly used to shut off, release, dose, distribute or mix fluids. For that reason, they are found in many application areas. Solenoids generally offer fast and safe switching, long service life, high reliability, low control power and compact design. Solenoid valve applications include a broad range of industrial settings, including general on-off control, plant control loops, process control systems and various original equipment manufacturer applications, to name but a few.
For correct and accurate control functioning, solenoid valves must be configured and selected according to the particular application at hand. On the basis of the calculated Kv value, and the pressure range of the planned application, a correspondingly appropriate valve type and its required orifice can be determined.
Standard interfaces are useful for actuator mountings because they help to keep solenoid manufacturing and installation costs down. The variety of different designs which are available enables a valve to be selected to specifically suit the application in question.
Solenoid valves are control units which, when electrically energized or de-energized, either shut off or allow fluid flow. The actuator takes the form of an electromagnet.
When energized, a magnetic field builds up which pulls a plunger or pivoted armature against the action of a spring. When de-energized, the plunger or pivoted armature is returned to its original position by the spring action. According to the mode of actuation, a distinction is made between direct-acting valves, internally piloted valves, and externally piloted valves. A further distinguishing feature is the number of port connections or the number of flow paths "ways".
With a direct-acting solenoid valve, the seat seal is attached to the solenoid core. In the de-energized condition, a seat orifice is closed, which opens when the valve is energized. Two-way valves are shut-off valves with one inlet port and one outlet port Fig. In the de-energized condition, the core spring, assisted by the fluid pressure, holds the valve seal on the valve seat to shut off the flow. When energized, the core and seal are pulled into the solenoid coil and the valve opens.
The electro-magnetic force is greater than the combined spring force and the static and dynamic pressure forces of the medium. Three-way valves have three port connections and two valve seats. One valve seal always remains open and the other closed in the de-energized mode. When the coil is energized, the mode reverses.
The 3-way valve shown in Fig. Various valve operations can be obtained according to how the fluid medium is connected to the working ports in Fig.
The fluid pressure builds up under the valve seat. With the coil de-energized, a conical spring holds the lower core seal tightly against the valve seat and shuts off the fluid flow. Port A is exhausted through R. When the coil is energized the core is pulled in, the valve seat at Port R is sealed off by the spring-loaded upper core seal. The fluid medium now flows from P to A. An isolating diaphragm ensures that the fluid medium does not come into contact with the coil chamber.
Pivoted-armature valves can be used to obtain any 3-way valve operation. The basic design principle is shown in Fig. Pivoted-armature valves are provided with manual override as a standard feature. With direct-acting valves, the static pressure forces increase with increasing orifice diameter which means that the magnetic forces, required to overcome the pressure forces, become correspondingly larger.
Internally piloted solenoid valves are therefore employed for switching higher pressures in conjunction with larger orifice sizes; in this case, the differential fluid pressure performs the main work in opening and closing the valve. Internally piloted solenoid valves are fitted with either a 2- or 3-way pilot solenoid valve. A diaphragm or a piston provides the seal for the main valve seat. The operation of such a valve is indicated in Fig. When the pilot valve is closed, the fluid pressure builds up on both sides of the diaphragm via a bleed orifice.
As long as there is a pressure differential between the inlet and outlet ports, a shut-off force is available by virtue of the larger effective area on the top of the diaphragm. When the pilot valve is opened, the pressure is relieved from the upper side of the diaphragm. The greater effective net pressure force from below now raises the diaphragm and opens the valve.
In general, internally piloted valves require a minimum pressure differential to ensure satisfactory opening and closing.
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