The issue of how to fit non-original impellers
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Hello everyone. I have a question for consultation: Recently, I’ve been selecting several single-stage, single-suction horizontal pumps with relatively high flow rates—ranging from 1,500 to 1,600 m³/h. There are very few manufacturers capable of producing single-suction pumps with such high flow rates. Initially, I considered Manufacturer A; however, their model with this flow rate doesn’t come with a stainless-steel impeller. Then I found Manufacturer B, which does offer a stainless-steel impeller. But the overall price of the pump from Manufacturer B is significantly higher than that from Manufacturer A. Considering the price, is it possible to purchase the stainless-steel impeller from Factory B for use in the pump at Factory A? Both Plant A and Plant B use the same model: 350-300-315, with an impeller size of 315, and the motor power is identical. If it can be adapted, what should be taken into consideration? Generally speaking, is there a relevant standard governing the diameter of pump shafts? A few additional questions: 1. Many manufacturers’ pumps have the same parameters regarding flow rate, head, and power; the only difference is in efficiency. It seems like they all follow the same template, especially small and medium-sized factories. I’ve dealt with one factory that started producing double-suction pumps in the past two years. Such factories probably purchase ready-made hydraulic models, right? The efficiency of this sample seems to be slightly higher than that of many major manufacturers. Moreover, the efficiencies at minimum flow rate, rated flow rate, and maximum flow rate are all relatively high, with little difference between them—for instance, 84/86/86. In contrast, other manufacturers tend to have values like 78/86/82. It seems that such figures aren’t very realistic. Please provide some guidance. 2. Does the hydraulic model mainly refer to the impeller? Does it still include the pump casing, flow channels, etc.? For example, for models 350-300-315, there are several power ratings available: 160 kW, 132 kW, and 110 kW. The pump body size remains the same, and their efficiencies are roughly comparable. For example, the pump body size of 350-300-315 is larger than that of 250-200-315; then, if an impeller with power ratings of 75/55/45/37 from the 250-200-315 model is installed in the pump body of 350-300-315, will its flow rate, head, and efficiency be the same as those of the 250-200-315 model, or will there be little to no impact, or will there be a significant impact? Thank you!
Various organizations take this aspect into consideration, and many details require the establishment of their own property rights. For example, structural changes, selection of bearings,,,,. What he fears are matters related to specifications; therefore, he wants to restrict your “after-sales service”. For some machined parts, it’s even impossible to locate and measure them; typically, you’re given a part drawing number, and the parts are supplied according to that number. It’s likely that the company isn’t yours either; since they’ve set a price, there’s no way to argue with it in an environment without competition. I have worked on maintenance in steel mills, so I have plenty of experience in this area; it’s just for reference.
The flow rate of the single-suction pump is 1500–1600 m3/h, which is indeed quite high. Why use a single-suction pump instead of a double-suction pump? With double-suction pumps, the range of options is very wide
You think too much and too deeply. It is also recommended not to use stainless steel impellers from Factory B in pumps from Factory A; if they work well, that’s one thing, but if they don’t, it can easily lead to disputes.
Thank you, there indeed are issues in these areas.
Definitely cannot be bought together; most of them won’t fit. It may be installed, unless A and B are in a hierarchical relationship. The hydraulic unit consists of an impeller and a housing.
The main issue is that if you buy it this way, what will happen if there are problems after purchase? Also, why can’t Manufacturer A produce impellers made of stainless steel for the pump as you mentioned? Is it due to mold issues?
1. You can discuss this matter with the two parties; if they can reach an agreement, then you won’t have any problems. You don’t need to worry about whether it’s compatible or not – let those two parties handle that. All you need to ensure is that the parameters are satisfactory. 2. The molds should be from the same set; companies of normal scale do not develop new hydraulic systems. Developing such systems involves high risks and costs, and they are also prone to being stolen. Differences in efficiency can be attributed to variations in the precision of mold manufacturing, differences in the casting process or precision, differences in the precision of surface treatment, or even to whether the data provided by the technical staff is conservative enough. 3. Hydraulic components include parts such as impellers and pump casings that are related to the hydraulic-shaped surfaces; they refer not only to the impeller itself. These hydraulic components are designed to work together, and under normal circumstances they cannot be used interchangeably. A small impeller cannot be used in a large pump casing, as this will result in parameters that differ significantly from those specified in the design, leading to very low efficiency, since it is completely contrary to the intended design. What kind of performance can one expect when wearing shoes sized 45 in feet that are designed for size 40?