Pneumatic or electric? It’s not a new question. The merits of each have long been subject to discussion, but a fair amount of confusion continues to exist about which makes more sense for what. For example, are you considering replacing a compressor and 200 pneumatic cylinders with electric actuators because you think you’ll save on compressor costs? Or, perhaps you are thinking about building a new machine with pneumatics because 30 electric actuators are far too expensive. Make the wrong decision in either case and you could waste tens of thousands of dollars a year.
Experience shows seemingly identical rolling bearings operated under identical conditions may not last the same amount of time. In most cases, it is impractical to test a statistically significant number of bearings, so engineers rely on standardized bearing-life calculations to select and size bearings for a particular application. These calculations continue to evolve and become more accurate over time, reflecting the collective experience of the bearing industry, including recent advances in manufacturing, tribology, materials, end-user condition monitoring, and computation.
Research into bearing failures1 shows that just over half of them are a result of contamination of the bearing oil. Clearly, it is essential to ensure that this is minimized and, if possible, eliminated to achieve the optimum bearing life necessary to improve equipment reliability.
Spindles are one of the most expensive and sophisticated rotating components on the planet. They rotate at super high speeds with fits and tolerances 10 to 20 times what is required on other rotating devices, such as pumps or motors. If there ever were machines that needed to communicate their health and activity it would be spindles.
It turned out that the photoelectric sensor could only be adjusted to stay on all the time or off all the time when the cans were going by at any higher rate than Jog speed on the Seamer. We adjusted and adjusted the sensors. The sensors were replaced with new sensors. It did no good. The lines were stopped while we traced all the control and power wiring so we could try to determine if there was a problem in the wiring.
Process pump reliability logically involves a combination of fluid-related performance and design decisions that focus on engineering materials and the configuration of mechanical components. Recent case studies have pointed out improvement opportunities in the relative design conservatism found in certain process pump models. Combined with deficiencies in the training of personnel, it can be argued that pump reliability has not made as much progress as it perhaps could.
You may get the impression that implementing these steps will be costly and very difficult to achieve. The thing you need to bear in mind is: “You are already spending the money.” The only question is: “Are you getting the result from your pumping systems that you are looking for?” If you can create an environment that allows your entire team to become engaged in implementing these concepts, it will be the best investment you ever made.
Every component of a bolted flange joint has a maximum allowable stress level. The mating flanges will begin to rotate or warp at a defined stress threshold. The studs or bolts of a given specification also will yield or be stressed past their elastic properties at a defined level. Non-metallic and semi-metallic gaskets will crush under excessive applied stress loads.
Pump reliability is an old topic, but it is just as relevant today as it was the first time we heard it a few decades ago. There are some very good reasons to focus on improving pump reliability. The rewards for achieving pump reliability are great and the effort, on the surface, seems fairly simple. After all, most of the elements of reliability are just common sense. But Ralph Waldo Emerson expertly put this idea into perspective when he said: “Common sense is as rare as genius.”