Depending on their service and application, and the local jurisdictional requirements, all valves need to be replaced sooner or later. However, if you find that “sooner” happens more often than “later,” you may not be getting as much life out of your valves as you could be.
Here are five ways to extend the life of your valves.
Preventative maintenance
Preventative maintenance both makes your valves last longer and decreases the amount of repair they need. By putting your valves on a testing and maintenance schedule, for example, testing every 12 months with repair every three to five years, you can identify and take care of small problems before they become big ones that require replacement.
GE’s ValvKeep is a valve management system that allows you to keep track of all of the valves in your facility and the maintenance and repair work that has been done on them. You can use this data to understand how well your valves are performing and what factors may be affecting their lifespans.
Regular exercise
Exercise is just as essential for valve health as it is for your health! A valve that is installed but never operated can seize up and become a big hunk of fused metal, which can be a serious problem if you ever need the valve to work. For this reason, exercise in the form of testing should be a part of your regular valve maintenance program.
Protective coatings
For valves in corrosive applications, such as oilfield service, protective coatings can reduce wear and protect valves against damage from corrosive materials and high temperatures. For example, carbide coatings can extend the service life of valves up to three times. Thermal spray coatings applied using the high-velocity oxy-fuel (HVOF) process are especially effective for protecting valves in severe service conditions.
Field machining
Field machining is another on-site strategy for enhancing valve life. Over time, sealing surfaces such as those on a nozzle or a flange can become compromised. Field machining, also called on-site machining, is a cost-effective way to reestablish the sealing surface without having to remove the valve from the system.
Operating the equipment properly
Finally, the best way to get the peak performance and longest life out of your valves is to use them properly. This includes selecting the appropriate valve for each application and installing it correctly — if you install a valve that is tight up to 90% of the nameplate set pressure, but operate the system at 93%, your valve will not last as long as you would like.
When selecting and installing valves, keep in mind that your system operates as a whole, not as a collection of discrete parts. For example, if you are having problems with a control valve, the cause might actually be the centrifugal pumps. According to plant performance expert Mike Pemberton, the average pump efficiency is less than 40%, mainly due to valve throttling and oversizing, which consumes excess power and results in valve wear and tear. When pumps are operating at their best efficiency point (BEP), the rest of the system also performs better.
Companies spend millions of dollars every year replacing valves unnecessarily. Through proper operation, maintenance, and repair, you can extend the life of your valves — and save a significant amount of money in the process.