I would like to ask what adverse effects might occur if a metering pump operates for a long time at a flow rate much lower than its designed value!
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Dear colleagues, I’ve encountered a situation where the metering pump used at the dosing site is designed to deliver a flow rate of about 1 liter per hour, but the actual amount of chemical added is less than 0.1 liter per hour. Since the pump operates continuously, its stroke volume and dosing frequency are very low; as a result, the pump tends to break down easily under such conditions. The same pump, when used at another location with similar dosing requirements but with intermittent dosing, experiences a significantly longer lifespan. The intention behind using continuous dosing was to achieve a more uniform concentration of the chemical, but it turns out that this approach is detrimental to the pump. I’m not sure why the pump’s lifespan is reduced so much. I would appreciate any advice you can offer. Thank you!
If the pump’s stroke is reduced and the flow rate remains above 0.1 liters per hour, it will cause the pump to overheat; however, you said it breaks down easily, but it doesn’t seem like the overheating is that severe. Besides, such pumps are equipped with safety valves at their outlets; if the pump were to overpressure, the safety valve would have activated already. Incorrect pump selection. Suggestions: 1. Replace the pump ； 2. Add a return line at the pump outlet, connecting directly to it. To put it simply, it’s actually just a matter of slightly opening the safety valve bypass line.
Which brand of pump? The diaphragm in a diaphragm pump has a limited service life. When selecting a metering pump, its maximum flow rate should not be more than 10 times the actual flow rate required for use. Conversely, the operating flow rate should be at least 10% of the pump’s maximum flow rate; otherwise, accuracy cannot be guaranteed. Logically, those used for heavy work in Malaysia should have a longer lifespan than normal ones. If the installation was done correctly, it’s still necessary to check aspects such as the material choice and the lifespan of vulnerable components.
Reply to 2# guiyuw: What I mean is that the maximum flow rate of the pump is 1 liter. By reducing the stroke and frequency, the pump’s output can be brought down to around 0.02–0.05 liters (with a stroke of 20% and a frequency of 10%). Will this cause any damage to the pump? Is it not possible to reduce the flow rate by forcing the pump to work under higher pressure?