If a valve doesn’t operate, your course of doesn’t run, and that’s cash down the drain. Or worse, a spurious journey shuts the method down. Or worst of all, a valve malfunction results in a harmful failure. Solenoid valves in oil and gasoline applications management the actuators that move large process valves, together with in emergency shutdown (ESD) techniques. The solenoid needs to exhaust air to allow the ESD valve to return to fail-safe mode each time sensors detect a dangerous process situation. These valves should be quick-acting, durable and, above all, dependable to forestall downtime and the related losses that occur when a course of isn’t running.
And this is much more necessary for oil and gasoline operations where there’s restricted power obtainable, similar to remote wellheads or satellite offshore platforms. Here, solenoids face a double reliability problem. First, a failure to operate correctly can not solely cause pricey downtime, however a upkeep name to a remote location also takes longer and costs greater than a neighborhood repair. Second, to scale back the demand for energy, many valve manufacturers resort to compromises that really reduce reliability. This is bad enough for course of valves, however for emergency shutoff valves and other security instrumented systems (SIS), it is unacceptable.
Poppet valves are usually higher suited than spool valves for distant areas as a end result of they’re less complicated. 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 efficiency of a solenoid valve. Friction, media circulate, sticking of the spool, magnetic forces, remanence of electrical current and materials characteristics are all forces solenoid valve producers have to overcome to build the most reliable valve.
High spring force is key to offsetting these forces and the friction they cause. However, in low-power applications, most manufacturers should compromise spring force to permit the valve to shift with minimal power. The reduction in spring drive results in a force-to-friction ratio (FFR) as little as 6, though the generally accepted safety level is an FFR of 10.
Several elements of valve design play into the amount of friction generated. Optimizing every of these allows a valve to have greater spring drive whereas still sustaining a high FFR.
For instance, the valve operates by electromagnetism — a current stimulates the valve to open, permitting the media to move to the actuator and move the method valve. This media could also be air, however it could even be natural gasoline, instrument gasoline or even liquid. This is particularly true in distant operations that must use whatever media is on the market. This means there’s a trade-off between magnetism and corrosion. Valves in which the media comes in contact with the coil have to be manufactured from 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 end result, there is no residual magnetism after the coil is de-energized, which in flip allows quicker response times. This design additionally protects reliability by stopping contaminants within the media from reaching the internal workings of the valve.
Another issue is the valve housing design. Usually เกจวัดแรงดันออกซิเจน (high-force) spring requires a high-power coil to beat the spring strength. Integrating the valve and coil right into a single housing improves effectivity by preventing vitality loss, allowing for the utilization of a low-power coil, leading to less energy consumption with out diminishing FFR. This integrated coil and housing design also reduces heat, 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 lure warmth across the coil, virtually eliminates coil burnout issues and protects process availability and security.
Poppet valves are usually higher suited than spool valves for distant operations. The lowered complexity of poppet valves will increase reliability by lowering sticking or friction factors, and decreases the number of elements that may fail. Spool valves typically have giant dynamic seals and lots of require lubricating grease. Over time, especially if the valves are not cycled, the seals stick and the grease hardens, leading to larger friction that have to be overcome. There have been reports of valve failure as a outcome of moisture within the instrument media, which thickens the grease.
A direct-acting valve is your best option wherever possible in low-power environments. Not solely is the design much less complex than an indirect-acting piloted valve, but additionally pilot mechanisms often have vent ports that can admit moisture and contamination, resulting in corrosion and allowing the valve to stay in the open place even when de-energized. Also, direct-acting solenoids are specifically designed to shift the valves with zero minimum stress requirements.
Note that some bigger actuators require high circulate rates and so a pilot operation is important. In this case, you will want to verify that all components are rated to the same reliability score as the solenoid.
Finally, since most remote places are by definition harsh environments, a solenoid put in there should have robust building and have the ability to stand up to and function at excessive temperatures while still maintaining the identical reliability and security capabilities required in less harsh environments.
When choosing a solenoid management valve for a remote operation, it is possible to find a valve that doesn’t compromise performance and reliability to reduce power demands. Look for a excessive FFR, simple dry armature design, nice magnetic and heat conductivity properties and strong 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 vitality operations. He provides cross-functional expertise in application engineering and business development to the oil, fuel, petrochemical and power 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 presents expertise in new business improvement and buyer relationship administration to the oil, fuel, petrochemical and energy industries and is licensed as a pneumatic specialist by the International Fluid Power Society (IFPS).
Share