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Do you still remember the famous “Type B pump”? In the past, an extra second pump (or “B pump”) was usually a requirement for critical processes and was key to ensuring smooth operation ； There are already different technical solutions available. Ideally, intelligent monitoring tools will issue warnings before any actual problems arise with the pump. Moreover, in many cases where it is already standard, modifications can be carried out at a relatively low cost, but this may give operators a false sense of security. Monitoring is not a panacea; if the pump is poorly designed or improperly installed, even the best monitoring system can only provide very limited assistance. “The pump is fine; it’s only improper design or incorrect operation that causes the pump to fail. This has also been the consensus among speakers at process pump forums over the years. Apart from serious operational errors, most cases of pump failure are caused by changes in the medium being pumped or in the operating methods. So what problems arise when choosing the right pump? If the purchasing decision focuses primarily on the cost of purchasing the pump, it will ignore the life cycle cost, failing to take into account all investment, operational, and maintenance costs. It is more economical to design the pump in the best way from the start. However, this requires a precise definition of the parameters to be pumped, such as the material and operating conditions, as well as detailed information regarding the pumping task. Moreover, the information regarding the components and properties of the product to be pumped must be absolutely accurate. It is often the factory that makes continuous revisions during the planning process, in order to avoid missing, incorrect, or outdated basic information. But at certain times, it is necessary to order equipment such as pumps to ensure that the factory can start operating on schedule. If the pump manufacturer does not receive the revised plan data, operational problems will inevitably arise later on. This is one of the reasons why over-labeling remains a common practice: to avoid common problems. After all, if a pump turns out to be of insufficient size, the design is obviously incorrect, which makes the approach of using an oversized pump the preferred option. But this is a clear misunderstanding, not only because of the energy waste involved, but also because under partial-load operation, many components of this pump are subjected to increased pressure and load, in addition to issues such as vibration. Inverters: Some people, after studying a large number of books on pumps, believe that it is possible to assume temporarily that simply combining the motor with an inverter (FC) will ensure that the energy supplied is used in the most efficient way. But of course this is not true: an inverter cannot operate on its own in thin air, as it also consumes energy itself. Therefore, it is important to first clarify whether a frequency converter is actually needed. Under dynamically changing load conditions, the answer to this question is generally \"yes\", but depending on the specific industry, other factors such as soft starting and heat transfer to the medium need to be taken into account. Conversely, a pump operating under a constant load, or at a speed close to its operating point, is the most energy-efficient solution in all cases. In this case, choosing a more efficient and smaller drive may be more cost-effective. However, despite the many advantages of frequency converters, they can also experience problems, especially if they are used to actually compensate for or counteract the performance degradation associated with wear. But operators usually don’t even notice this until wear causes the pump to fail. Vibration: Vibration is the root cause of damage, but it is often underestimated. By design, displacement pumps experience pulsations of varying magnitude during operation, which is a well-known characteristic; these are usually addressed using pulsation dampers. Yet few people know that centrifugal pumps also have pulsation. This is because pressure oscillations occur when the system interacts with the pump, which can lead to a surge in pressure in the worst cases. If a pump develops a defect and no obvious cause can be found, these pressure surges may be the reason, as the forces generated as a result can be high enough to damage the bearings. Is there a single pump design for all applications? No. Cavities have always been a sign of pump failure. Here are 6 suggestions to keep in mind: Material: If you are concerned that the fluid may change over time, choose more stable materials as a precaution. Note: If failures occur frequently, it may be due to the failure to follow the cleaning procedures using acidic or alkaline solutions. Speed: Pumps connected in series can reach similar speeds; the best solution is to choose a larger speed difference. Dry run: A dry run protection device is installed to shut down the pump in case of a fault. Cavity: Ensure that the temperature of the liquid inside the pump is not too high, and that the suction pressure of the pump is not too low. Standard pumps: The advantage of standardization is that operators can reach a framework agreement with the manufacturer; thereafter, they only need to select the pump type that was agreed upon in advance. This not only saves time but also offers a highly attractive purchasing advantage. Experience sharing: it’s essential! On the process pump forums, this always comes first. Management of the operator company should realize that the employees involved in operations are returning to work with relatively cost-effective solutions to problems. To save a lot of money in the planning and maintenance of water pumps, operators should allocate more budget for this purpose. Failures in the hydraulic system – issues such as dry operation or cavitation can repeatedly cause severe damage to the pump system. In centrifugal pumps, it is essential to ensure that the pump is filled with the medium to be pumped, as dry operation is absolutely prohibited for mechanical seals. If a pump starts to make a creaking noise, similar to sand dropping on an iron roof, it means the pump needs to reach its maximum concentration. Because this is the sound of a cavity, and a cavity is always a sign of a pump failure. Due to the removal of material, the main victim is the impeller, and the extent of damage depends on the properties of the material. Stainless steel is more resistant to cavitation than bronze, and bronze is better able to resist cavities than cast iron. Furthermore, the cavity can also cause significant noise and vibration, which in turn can damage bearings, shaft seals, and welded joints. Correct weld joint: In principle, this is a critical point for conventional centrifugal pumps, as it is not usual, by nature of the system, to observe any slight leakage of the liquid pumped out at the shaft seal. Sealed pumps such as canned motor pumps and magnetic coupling pumps offer reliability because they do not use shaft seals. But which design is more reliable? If the safest and most reliable solution is required, canned motor pumps represent the most suitable technical choice, despite their higher cost. Furthermore, statistics from an old oil refinery in Germany show that the average mean time between failures for canned motor pumps is around 180 months, whereas it is 50 months for centrifugal pumps equipped with double-action mechanical seals. Therefore, the average failure-free operating time of canned motor pumps is approximately four times higher than that of centrifugal pumps equipped with double-action mechanical seals. Standardization: Whether it is internal operators or external engineering service providers, there is often a need for people who can plan complex industrial plants, especially those who do not have a good understanding of modern pump technology. Because this allows for constraints to be applied within certain designs, and by reducing the number of variables subject to such constraints, it helps to minimize the occurrence of meaningless outcomes. Moreover, the standardization of impellers, materials, O-rings, and mechanical seals also helps to simplify factory operations. Is there a proven exclusion procedure? Or in other words, is there a single pump design for all uses? The short answer is: No! But there are also some solutions that cover a wide range of applications. Since the goal is clear, the fewer different series that are used, the fewer different spare parts that need to be kept in stock. Moreover, the maintenance technicians on site have a better understanding of standard pumps compared to more complex variable pumps or completely different types of pumps. Similarly, this also applies to operators, as many pump failures are caused by incorrect starting and stopping procedures of the pumps. In summary, when ordering a pump, there are few sufficiently accurate data available for proper design, possibly because not much can be done in this regard. Planners are under time pressure and will not allow any delays. Pump manufacturers are also unable to arbitrarily influence the “delivery time” through leverage; it is recommended to use the following approach to solve this issue: select speed control pumps with higher quality materials ； Inductive flow regulators help ensure that the delivery rate is neither below nor above the permitted range. Moreover, a reliable monitoring system helps staff work and rest better!