The centrifugal pump is used for the maintenance and calibration of the backflow device
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The dosing room at Oil and Gas Metering Station No. 3 is equipped with 2 demulsifier dosing pumps, whose reflux systems feature safety pressure relief functions; during operation, reflux is generated at the pump outlet to address any overpressure conditions there. When asked, the personnel on site were unable to explain how to calibrate and maintain the backflow device; the maintenance procedures for diaphragm metering pumps (JX60/1.4A-0.55-324S) did not contain any information regarding the calibration and maintenance of such devices, which resulted in inadequate maintenance of the equipment. These are the issues identified during the inspection. May I ask what exactly is meant by the calibration and maintenance of the reflux device, and how should this work be carried out?
“What is the origin and meaning of the term “calibration and maintenance of the reflux device”? It would be best to have a simple diagram; it’s easier to give an accurate description when looking at a picture. It is necessary to clarify whether the dosing pump is connected to the pressure system in the process. As for diaphragm metering pumps, they have a simple structure; usually, one needs to disassemble them to check whether the internal diaphragm is damaged, as well as the relevant bearings and check valves. As for backflow pressure regulation, it is simply done by using a pressure gauge as a reference point to control the pressure at the pump outlet. It can also be controlled using safety valves, pressure relief valves, and other control valves. I’m not sure which part refers to the meaning of “calibration”; please clarify.
The issue raised with us is that the backflow device has not been calibrated or maintained. The diaphragm pump we use on site is relatively simple in design, consisting of an inlet pipeline and an outlet pipeline, with a check valve installed on the outlet pipeline. I just don’t know which part needs to be calibrated
The one who tied the knot must untie it; it’s better to consult the person who raised the question.
Do you know anything about the maintenance of reflux devices? Could you provide some references? Thank you
It would be best to send a schematic diagram or a flowchart; it’s easier to convey the meaning accurately by looking at the diagram. There are a wide range of backflow prevention devices; a valve can be used, as well as automatic regulation systems. Safety valves can also be employed as pressure relief valves. It’s best to refine the question for reference.
1. First of all, there’s a problem with your title – you’re referring to diaphragm pumps here, not centrifugal pumps; the two are quite different in nature! Diaphragm pumps belong to the category of positive displacement pumps; according to their working principle, the outlet pressure can be increased indefinitely, whereas this is not possible with centrifugal pumps! 2. The backflow line you mentioned is used in both diaphragm pumps and centrifugal pumps, but its functions differ. Diaphragm pumps are used to prevent overpressure at the outlet, while centrifugal pumps are primarily intended to ensure a minimum flow rate and prevent cavitation. 3. Since this is a diaphragm pump, the function of its return line is to prevent overpressure; therefore, the relevant maintenance and calibration standards are determined based on its maximum outlet pressure. It is necessary to contact the manufacturer or find the relevant equipment parameters on one’s own in order to set them. If a valve is used as the control element for the return line, the simplest and most practical method is to fully open the valve on the return line and close the outlet valve; then, by gradually closing the valve on the return line, its pressure can be kept within the maximum allowable range for the diaphragm pump. The above views are my personal suggestions and are for reference only!