If a valve doesn’t operate, your course of doesn’t run, and that is money down the drain. Or worse, a spurious journey shuts the process down. Or worst of all, a valve malfunction leads to a dangerous failure. Solenoid valves in oil and gas functions control the actuators that transfer giant course of 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 process scenario. These valves must be quick-acting, sturdy and, above all, dependable to stop downtime and the related losses that happen when a course of isn’t running.
And that is much more necessary for oil and fuel operations the place there’s limited energy obtainable, similar to remote wellheads or satellite tv for pc offshore platforms. Here, solenoids face a double reliability problem. First, a failure to operate correctly can not solely trigger expensive downtime, however a maintenance name to a distant location additionally takes longer and prices more than an area repair. Second, to reduce back the demand for power, many valve producers resort to compromises that truly reduce reliability. This is dangerous sufficient for course of valves, however for emergency shutoff valves and different security instrumented methods (SIS), it’s unacceptable.
Poppet valves are usually higher suited than spool valves for distant locations as a result of they’re much less advanced. 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 factors can hinder the reliability and performance of a solenoid valve. Friction, media move, sticking of the spool, magnetic forces, remanence of electrical current and material traits are all forces solenoid valve producers have to overcome to construct probably the most dependable valve.
High spring force is essential to offsetting these forces and the friction they cause. However, in low-power functions, most manufacturers have to compromise spring force to permit the valve to shift with minimal energy. The reduction in spring drive results in a force-to-friction ratio (FFR) as little as 6, although the generally accepted safety level is an FFR of 10.
Several parts of valve design play into the amount of friction generated. Optimizing every of those allows a valve to have higher spring pressure whereas still sustaining a high FFR.
For example, the valve operates by electromagnetism — a current stimulates the valve to open, permitting the media to move to the actuator and transfer the method valve. This media may be air, but it could also be natural gas, instrument gasoline and even liquid. This is very true in remote operations that must use no matter media is on the market. ตัววัดแรงดันน้ำ means there is a trade-off between magnetism and corrosion. Valves by which the media is out there in contact with the coil should be made from anticorrosive supplies, 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 faster response instances. 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 energy. Integrating the valve and coil right into a single housing improves efficiency by preventing vitality loss, allowing for the utilization of a low-power coil, leading to less power consumption without diminishing FFR. This built-in coil and housing design additionally reduces warmth, stopping spurious journeys 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 trap heat around the coil, virtually eliminates coil burnout considerations and protects course of availability and safety.
Poppet valves are typically higher suited than spool valves for remote operations. The lowered complexity of poppet valves increases reliability by lowering sticking or friction factors, and reduces the number of parts that may fail. Spool valves usually have giant dynamic seals and plenty of require lubricating grease. Over time, particularly if the valves are not cycled, the seals stick and the grease hardens, leading to larger friction that must be overcome. There have been reports of valve failure due to moisture within the instrument media, which thickens the grease.
A direct-acting valve is your finest option wherever potential in low-power environments. Not solely is the design less complicated than an indirect-acting piloted valve, but in addition 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 minimum strain requirements.
Note that some bigger actuators require high flow rates and so a pilot operation is necessary. In this case, you will want to confirm that all elements are rated to the same reliability rating as the solenoid.
Finally, since most distant locations are by definition harsh environments, a solenoid installed there must have robust construction and have the flexibility to withstand and function at excessive temperatures while still maintaining the same reliability and security capabilities required in less harsh environments.
When selecting a solenoid management valve for a distant operation, it is possible to find a valve that doesn’t compromise performance and reliability to reduce power calls for. Look for a high FFR, easy dry armature design, nice magnetic and heat conductivity properties and sturdy development.
Andrew Barko is the gross 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 application engineering and business improvement to the oil, fuel, petrochemical and power industries and is licensed 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 presents experience in new enterprise growth and customer relationship administration to the oil, gas, petrochemical and energy industries and is certified as a pneumatic specialist by the International Fluid Power Society (IFPS).
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