Solenoid valve reliability in lower energy operations

If a valve doesn’t operate, your process doesn’t run, and that is money down the drain. Or worse, a spurious trip shuts the process down. Or worst of all, a valve malfunction results in a dangerous failure. Solenoid valves in oil and gas functions management the actuators that move massive course of valves, including in emergency shutdown (ESD) methods. The solenoid needs to exhaust air to allow the ESD valve to return to fail-safe mode every time sensors detect a dangerous process state of affairs. These valves have to be quick-acting, durable and, above all, dependable to stop downtime and the related losses that happen when a course of isn’t working.
And that is much more necessary for oil and fuel operations the place there is restricted energy obtainable, similar to remote wellheads or satellite tv for pc offshore platforms. Here, solenoids face a double reliability challenge. First, a failure to function appropriately cannot only trigger expensive downtime, but a maintenance call to a distant location additionally takes longer and prices greater than an area repair. Second, to reduce the demand for power, many valve producers resort to compromises that really scale back reliability. This is bad sufficient for course of valves, but for emergency shutoff valves and different security instrumented techniques (SIS), it is unacceptable.
Poppet valves are typically better suited than spool valves for remote areas as a result of they’re less complicated. For low-power purposes, 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 elements can hinder the reliability and efficiency of a solenoid valve. Friction, media circulate, sticking of the spool, magnetic forces, remanence of electrical present and materials characteristics are all forces solenoid valve producers have to beat to build the most reliable valve.
High spring drive is essential to offsetting these forces and the friction they cause. However, in low-power purposes, most manufacturers have to compromise spring pressure to allow the valve to shift with minimal power. The discount in spring drive results in a force-to-friction ratio (FFR) as low as 6, although the widely accepted security degree is an FFR of 10.
Several parts of valve design play into the amount of friction generated. Optimizing every of these permits a valve to have larger spring drive whereas nonetheless maintaining a high FFR.
For example, the valve operates by electromagnetism — a current stimulates the valve to open, permitting the media to flow to the actuator and move the process valve. This media may be air, however it may also be natural fuel, instrument gas and even liquid. This is very true in distant operations that must use whatever media is out there. This means there is a trade-off between magnetism and corrosion. Valves during which the media comes in contact with the coil must be made from anticorrosive materials, which have poor magnetic properties. A valve design that isolates the media from the coil — a dry armature — permits using highly magnetized material. As a result, there is no residual magnetism after the coil is de-energized, which in flip permits faster response occasions. This design additionally protects reliability by stopping contaminants in the media from reaching the inner workings of the valve.
เกจวัดแรงดันถังแก๊ส is the valve housing design. Usually a heavy (high-force) spring requires a high-power coil to overcome the spring energy. Integrating the valve and coil into a single housing improves effectivity by preventing vitality loss, allowing for the usage of a low-power coil, leading to less power consumption with out diminishing FFR. This built-in coil and housing design additionally reduces warmth, preventing spurious trips or coil burnouts. A dense, thermally environment friendly (low-heat generating) coil in a housing that acts as a warmth sink, designed with no air gap to lure warmth around the coil, virtually eliminates coil burnout concerns and protects course of availability and safety.
Poppet valves are usually 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 components that can fail. Spool valves usually have massive dynamic seals and lots of require lubricating grease. Over time, particularly if the valves usually are not cycled, the seals stick and the grease hardens, resulting in larger friction that have to be overcome. There have been reviews of valve failure due to moisture within the instrument media, which thickens the grease.
A direct-acting valve is your greatest option wherever attainable in low-power environments. Not only is the design much less advanced than an indirect-acting piloted valve, but additionally pilot mechanisms typically have vent ports that may admit moisture and contamination, leading to corrosion and permitting the valve to stick in the open place even when de-energized. Also, direct-acting solenoids are specifically designed to shift the valves with zero minimum strain necessities.
Note that some larger actuators require excessive flow charges and so a pilot operation is important. In this case, it is necessary to ascertain that each one parts are rated to the identical reliability rating as the solenoid.
Finally, since most remote locations are by definition harsh environments, a solenoid installed there must have sturdy development and be ready to stand up to and operate at excessive temperatures whereas nonetheless sustaining the identical reliability and security capabilities required in less harsh environments.
When choosing a solenoid control valve for a remote operation, it’s potential to discover a valve that doesn’t compromise performance and reliability to scale back power calls for. Look for a high FFR, simple dry armature design, nice magnetic and heat conductivity properties and robust construction.
Andrew Barko is the sales engineer for the Energy Sector of IMI Precision Engineering, makers of IMI Norgren, IMI Maxseal and IMI Herion model components for power operations. He presents cross-functional expertise in application engineering and enterprise development to the oil, fuel, petrochemical and energy industries and is certified as a pneumatic Specialist by the International Fluid Power Society (IFPS).
Collin Skufca is the key account supervisor for the Energy Sector for IMI Precision Engineering. He offers experience in new enterprise improvement and customer relationship management to the oil, gasoline, petrochemical and power industries and is certified as a pneumatic specialist by the International Fluid Power Society (IFPS).
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