Solenoid valve reliability in decrease power operations

If a valve doesn’t operate, your process doesn’t run, and that’s cash down the drain. Or worse, a spurious trip shuts the process down. Or worst of all, a valve malfunction results in a harmful failure. Solenoid valves in oil and gas applications management the actuators that move giant course of valves, including in emergency shutdown (ESD) systems. The solenoid must exhaust air to allow the ESD valve to return to fail-safe mode whenever sensors detect a dangerous process scenario. These valves have to be quick-acting, durable and, above all, dependable to prevent downtime and the associated losses that happen when a process isn’t working.
And this is much more necessary for oil and gas operations where there’s limited power obtainable, such as remote wellheads or satellite tv for pc offshore platforms. Here, solenoids face a double reliability problem. First, a failure to function appropriately can not solely trigger expensive downtime, but a maintenance name to a remote location additionally takes longer and costs greater than a neighborhood restore. Second, to minimize back the demand for power, many valve manufacturers resort to compromises that truly scale back reliability. This is bad enough for course of valves, but for emergency shutoff valves and other security instrumented techniques (SIS), it’s unacceptable.
Poppet valves are typically better suited than spool valves for remote areas because they’re much less advanced. For low-power applications, look 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 reliable low-power solenoid
Many factors can hinder the reliability and performance of a solenoid valve. Friction, media flow, sticking of the spool, magnetic forces, remanence of electrical current and material characteristics are all forces solenoid valve manufacturers have to overcome to build essentially the most dependable valve.
High spring drive is vital to offsetting these forces and the friction they cause. However, in low-power functions, most producers have to compromise spring force to permit the valve to shift with minimal energy. The discount in spring pressure results in a force-to-friction ratio (FFR) as low as 6, though the widely accepted security degree is an FFR of 10.
Several components of valve design play into the quantity of friction generated. Optimizing each of these allows a valve to have greater spring force while still maintaining a high FFR.
For instance, the valve operates by electromagnetism — a current stimulates the valve to open, allowing the media to move to the actuator and move the method valve. This media could also be air, however it might also be natural fuel, instrument gas and even liquid. This is particularly true in distant operations that should use whatever media is out there. This means there is a trade-off between magnetism and corrosion. Valves in which the media is out there in contact with the coil should be manufactured from anticorrosive supplies, which have poor magnetic properties. A valve design that isolates the media from the coil — a dry armature — permits using highly magnetized materials. As a outcome, there is not any residual magnetism after the coil is de-energized, which in flip permits faster response instances. This design additionally protects reliability by preventing contaminants in the media from reaching the inside workings of the valve.
Another factor is the valve housing design. Usually a heavy (high-force) spring requires a high-power coil to overcome the spring power. Integrating the valve and coil right into a single housing improves effectivity by preventing vitality loss, permitting for using a low-power coil, leading to less power consumption with out diminishing FFR. This integrated coil and housing design also reduces heat, stopping spurious trips or coil burnouts. A dense, thermally efficient (low-heat generating) coil in a housing that acts as a warmth sink, designed with no air hole to entice warmth across the coil, nearly eliminates coil burnout concerns and protects course of availability and security.
Poppet valves are generally higher suited than spool valves for distant operations. The lowered complexity of poppet valves increases reliability by decreasing sticking or friction factors, and reduces the variety of parts that can fail. Spool valves usually have massive dynamic seals and lots of require lubricating grease. Over time, particularly if the valves aren’t cycled, the seals stick and the grease hardens, resulting in higher friction that must be overcome. There have been stories of valve failure because of moisture in the instrument media, which thickens the grease.
เกจไนโตรเจนsumo -acting valve is the best choice wherever attainable in low-power environments. Not solely is the design less complicated than an indirect-acting piloted valve, but additionally pilot mechanisms often have vent ports that can admit moisture and contamination, leading to 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 minimal strain necessities.
Note that some larger actuators require excessive flow rates and so a pilot operation is important. In this case, it could be very important verify that each one components are rated to the identical reliability ranking because the solenoid.
Finally, since most distant areas are by definition harsh environments, a solenoid installed there should have sturdy construction and be succesful of withstand and operate at excessive temperatures while still maintaining the identical reliability and safety capabilities required in much less harsh environments.
When deciding on a solenoid management valve for a distant operation, it is potential to find a valve that doesn’t compromise efficiency and reliability to scale back energy demands. Look for a high FFR, easy dry armature design, nice magnetic and heat conductivity properties and strong development.
Andrew Barko is the sales engineer for the Energy Sector of IMI Precision Engineering, makers of IMI Norgren, IMI Maxseal and IMI Herion brand parts for power operations. He presents cross-functional expertise in application engineering and business growth to the oil, gasoline, petrochemical and energy industries and is certified as a pneumatic Specialist by the International Fluid Power Society (IFPS).
Collin Skufca is the key account manager for the Energy Sector for IMI Precision Engineering. He offers experience in new business growth and buyer relationship administration to the oil, gas, petrochemical and power industries and is licensed as a pneumatic specialist by the International Fluid Power Society (IFPS).
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