If a valve doesn’t operate, your process doesn’t run, and that’s cash down the drain. Or worse, a spurious journey shuts the process down. Or worst of all, a valve malfunction leads to a harmful failure. Solenoid valves in oil and gasoline applications control the actuators that transfer giant process valves, together with in emergency shutdown (ESD) methods. The solenoid must exhaust air to allow the ESD valve to return to fail-safe mode whenever sensors detect a dangerous course of scenario. These valves must be quick-acting, durable and, above all, dependable to stop downtime and the associated losses that occur when a course of isn’t running.
And that is even more necessary for oil and gas operations the place there’s restricted power available, similar to remote wellheads or satellite tv for pc offshore platforms. Here, solenoids face a double reliability problem. First, a failure to operate accurately can’t only cause expensive downtime, but a maintenance name to a distant location additionally takes longer and costs more than an area repair. Second, to minimize back the demand for power, many valve manufacturers resort to compromises that really scale back reliability. This is dangerous enough for process valves, but for emergency shutoff valves and different security instrumented techniques (SIS), it is unacceptable.
Poppet valves are generally better suited than spool valves for distant locations as a end result of they’re much less complex. For low-power functions, search for a solenoid valve with an FFR of 10 and a design that isolates the media from the coil. (Courtesy of Norgren Inc.)
Choosing a dependable low-power solenoid
Many components can hinder the reliability and efficiency of a solenoid valve. Friction, media move, sticking of the spool, magnetic forces, remanence of electrical present and materials traits are all forces solenoid valve manufacturers have to beat to build essentially the most dependable valve.
High spring force is essential to offsetting these forces and the friction they trigger. However, in low-power applications, most manufacturers should compromise spring force to allow the valve to shift with minimal energy. The reduction in spring force leads to a force-to-friction ratio (FFR) as low as 6, though the widely accepted security level is an FFR of 10.
Several parts of valve design play into the amount of friction generated. Optimizing each of these allows a valve to have greater spring force whereas nonetheless sustaining a excessive FFR.
For example, the valve operates by electromagnetism — a current stimulates the valve to open, allowing the media to flow to the actuator and move the process valve. This media could also be air, but it might even be pure gasoline, instrument gas and even liquid. This is very true in remote operations that should use whatever media is on the market. This means there is a trade-off between magnetism and corrosion. Valves during which the media is obtainable in contact with the coil have to be made of anticorrosive materials, which have poor magnetic properties. A valve design that isolates the media from the coil — a dry armature — allows the use of highly magnetized materials. As a outcome, there isn’t any residual magnetism after the coil is de-energized, which in turn permits quicker response times. This design also protects reliability by preventing contaminants within the media from reaching the inside workings of the valve.
Another issue is the valve housing design. Usually a heavy (high-force) spring requires a high-power coil to overcome the spring strength. Integrating the valve and coil right into a single housing improves effectivity by stopping energy loss, permitting for the use of a low-power coil, leading to less energy consumption without diminishing FFR. This built-in coil and housing design additionally reduces heat, preventing spurious journeys or coil burnouts. compound gauge ราคา , thermally environment friendly (low-heat generating) coil in a housing that acts as a heat sink, designed with no air hole to lure warmth around the coil, just about eliminates coil burnout issues and protects course of availability and security.
Poppet valves are typically higher suited than spool valves for distant operations. The reduced complexity of poppet valves increases reliability by decreasing sticking or friction factors, and decreases the variety of parts that can fail. Spool valves often have large dynamic seals and many require lubricating grease. Over time, especially if the valves aren’t cycled, the seals stick and the grease hardens, resulting in larger friction that must be overcome. There have been reviews of valve failure due to moisture in the instrument media, which thickens the grease.
A direct-acting valve is the finest choice wherever possible in low-power environments. Not solely is the design much less complicated than an indirect-acting piloted valve, but additionally pilot mechanisms often have vent ports that may admit moisture and contamination, resulting in corrosion and permitting the valve to stay in the open position even when de-energized. Also, direct-acting solenoids are specifically designed to shift the valves with zero minimum pressure necessities.
Note that some bigger actuators require high circulate charges and so a pilot operation is critical. In this case, it may be very important ascertain that all elements are rated to the identical reliability ranking as the solenoid.
Finally, since most remote areas are by definition harsh environments, a solenoid put in there will must have robust building and be able to face up to and operate at extreme temperatures whereas still maintaining the same reliability and safety capabilities required in much less harsh environments.
When selecting a solenoid management valve for a remote operation, it’s attainable to discover a valve that does not compromise performance and reliability to minimize back power calls for. Look for a excessive FFR, simple dry armature design, nice magnetic and warmth conductivity properties and sturdy building.
ที่วัดแรงดันน้ำ is the sales engineer for the Energy Sector of IMI Precision Engineering, makers of IMI Norgren, IMI Maxseal and IMI Herion model elements for vitality operations. He presents cross-functional experience in utility engineering and enterprise growth to the oil, gasoline, petrochemical and energy industries and is licensed as a pneumatic Specialist by the International Fluid Power Society (IFPS).
Collin Skufca is the important thing account manager for the Energy Sector for IMI Precision Engineering. He offers expertise in new business growth and buyer relationship administration to the oil, gas, petrochemical and power industries and is certified as a pneumatic specialist by the International Fluid Power Society (IFPS).
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