Reasons for asking for help with canned pump mediation
Thread Content
There is a canned pump in the factory that transports hot oil as a medium. The temperature is about 220°C and the outlet pressure is 0.2MPa. Previously, the entire section was shut down because the pump tripped. Is there any experienced driver who can analyze the various reasons for the canned pump tripping.
Generally speaking, as long as the pump is selected correctly, there will be no problems. But if there is a problem, it's hard to say. There are many reasons, including the pump itself, operating conditions, etc.
Looking at the outline diagram in Figure 1 of the poster's medium temperature, it should be a high-temperature canned pump with a heat exchanger (it feels like a pump from a Dalian company). Personally, I think that as long as the operation of the canned pump is stable and there are no operational fluctuations such as process evacuation, the possibility of pump failure and tripping is small. (My unit has two basic models and two high-temperature models, and they have not broken down or been repaired once in more than 5 years of use! ) As for the jump stop, I wonder if the original poster has dismantled it later? Is it caused by excessive vibration of the graphite bearing caused by high inlet pipe resistance and evacuation, or by improper exhaust before starting the pump? Look at Figure 1. This pump should have a TRG meter. What color is the display area on the meter? ? I agree with what the 2nd floor said, and I suggest that the original poster should judge the reason for the pump tripping and stopping based on the process flow, process operating parameters, and the internal conditions of the pump itself being disassembled and repaired! I hope that the poster will follow up and update this post. I will pay close attention and learn from it. * Find out the cause of the failure.
Putting aside the pump, process and other reasons, just analyze the photos (not necessarily correct): pump mediation: 1. Current overload 2. Motor thermal protection action 1. The wear condition can be found from mechanical wear or disassembly, and it can be roughly judged whether it is current action 2. The motor of this pump is a conventional motor with a temperature resistance of 180-220 degrees. The 220-degree medium requires cooling of the rear heat exchanger and motor water jacket to ensure that the motor operating temperature is appropriate. ； Looking at the photo, the heat exchanger has been replaced. It is very likely that the heat exchange in this part is insufficient or the internal circulating fluid is insufficient, causing the temperature of the rear cavity to be too high. The thermal protection mediates. ----When the pump cools down and nothing moves, it can be driven again. This is basically the problem, but the heat exchange problem still needs to be solved.
The heat exchanger uses ordinary circulating water, and the temperature of the medium in the pump cavity is relatively high, so during maintenance, it was found that the heat exchanger was severely fouled. It has been equipped for 6 years, so there must be something wrong with the circuit system.
The heat exchanger uses ordinary circulating water, and the temperature of the medium in the pump cavity is relatively high, so during maintenance, it was found that the heat exchanger was severely fouled. It has been equipped for 6 years, so there must be something wrong with the circuit system.
So what are the specific reasons? Can you give us an analysis?
The pump was being inspected on a day off, so the specific reason is not clear. My colleagues who participated in the inspection said that no abnormalities were found, and then it was reinstalled and put into standby.
If you disassemble the machine and find that there are no problems with the rotating parts, it can basically be determined that the heat exchange of the motor part is insufficient, causing the motor thermal protection action! It shouldn't be a circuit system problem. 1. The water jacket needs to be cleaned. It may be insufficient heat exchange caused by insufficient cooling water - directly measuring the inlet and outlet temperature of the heat exchanger installed by yourself can preliminarily determine the heat exchange effect. 2. Verify whether the heat exchanger you replaced can meet the cyclic use of the pump. That is to say, the heat exchanger effect is good, but the amount of circulating hot oil is insufficient, and it cannot achieve the originally designed motor cooling effect. -You can find out by measuring the surface temperature of the motor. Please look at these two places.