First, Heat Exchanger is insufficient
Generally, it is caused by the following factors: too small type selection, insufficient steam capacity, poor discharge of condensate water, blocked waterways, undischarged air in heat exchanger, serious scale formation in heat exchanger, etc.
1. Selection is too small
Under the condition of no problem in circulating water flow and heating steam flow, the heat exchange requirement can only be met when the steam inlet pressure is high, and the discharge temperature of condensate water is high.Once the steam pressure is reduced, it is impossible to ensure that heat exchange, this kind of situation is generally caused by too small radiator selection.Selection is too small, condensate discharge temperature is high, resulting in heat waste.And when the steam pressure can not ensure the normal heat supply, should replace or add heat exchanger in time.
2. There isn't enough steam
The result shows that the heat exchange cannot be guaranteed when the steam inlet pressure of the heat exchanger is low.Check that the pressure reducing valve is adjusted correctly.If the pressure in front of the relief valve is low and the relief valve cannot be started, the relief valve bypass valve should be opened.If the pressure before the main steam valve is too low, should check the steam network and steam source, as long as the steam pressure is solved, heat exchange can be guaranteed.
3. Condensation water discharge is not free
If the trap is blocked, it can be solved in time by cleaning the trap.In addition, the design of the condensate pipe is too small, will also cause the condensate discharge is not free, causing difficulty in the regulation of heat exchange.In this case to increase the size of the condensate pipe to solve.
4. Waterways blocked
Characteristics: the temperature difference between outlet and inlet of heat exchanger is large, the difference between inlet and outlet water pressure is large, and the temperature of condensate water is high, and the heat exchange is insufficient.The water circulation flow of the heat exchanger is reduced and the heat transfer coefficient is reduced.Treatment: one is to carry out backwash, two is to disassemble the heat exchanger clean.The reason for the water channel blockage of heat exchanger is that the external pipe network especially the newly built pipe network is full of impurities and the decontamination capacity of the decontaminator is very poor.The decontamination apparatus should be modified in time to improve its performance and regularly discharge the pollutants in the apparatus.In addition, the construction management of the newly built pipe network should be strengthened. Foreign matters in the pipe must be cleaned during the installation process. The newly built pipe network should be flushed and connected with the network.
5. The road is blocked
Characteristics: The temperature difference between inlet and outlet is small, the temperature of condensate is low (almost the same as the temperature of inlet), but the steam pressure is not low.Treatment method: First, check whether the trap is blocked and whether the drainage amount of the drainage pipe meets the requirements;Next check the steam filter and steam inlet valve.If there is no filter in the steam pipe, the possibility of steam blockage in the heat exchanger should be considered.Whether the steam line of heat exchanger is blocked or not is related to the quality of pipeline cleaning after the construction of steam pipeline.The heat exchanger should be disassembled and cleaned when the steam path of the heat exchanger is blocked seriously.
6. The air in the heat exchanger is not discharged
This can be avoided by paying attention to the discharge of air from the heat exchanger during initial operation and checking the exhaust during operation.
7. Serious scaling in the heat exchanger
The reason of fouling in heat exchanger is the poor quality of circulating water.Prevention is to control the quality of circulating water;Second, the scope of quantity regulation and quality regulation should be controlled reasonably;Third, efforts should be made to reduce the loss of water network.Scaling of heat exchanger results in low outlet temperature, high discharge temperature of condensate water and greatly reduced efficiency of heat exchanger.Treatment: one is to disassemble the heat exchanger to clean, the other is to carry out chemical cleaning of the heat exchanger.
Second. Insufficient circulating water flow
If the heating users continue to increase, but the pump is still the original pump, it will cause insufficient circulating water flow in the system. The circulating pump should be replaced or the number of circulating pumps should be increased.The deficiency of circulating water flow is characterized by large temperature difference between water supply and return water.The main pump should be checked whether the gas or blockage, impeller whether wear or whether there are other problems affecting the pump performance.Check the inlet and outlet valves of the circulating pump, check valves of the bypass pressure relief pipe of the circulating pump and the decontaminator, etc.Decontamination device blockage (decontamination device before and after the pressure difference is too large) will cause the circulation pump inlet pressure is too low, or even pump, affect the circulation water flow.If after the decontamination device clean, pump inlet pipe is still evacuated, generally is the design of the decontamination device caused by insufficient flow, should be modified decontamination device, increase its flow.
Third, heat exchanger internal water hammer
Water hammer in heat exchanger is usually caused by high condensate water level in heat exchanger.Generally, it can be solved by increasing the discharge of condensate.Also can suspend steam, will condensate after discharge into steam.
Fourth, heat exchanger leakage
Heat exchanger leakage is divided into two kinds: external leakage and internal leakage.Leakage is easy to find, according to the causes of leakage to take corresponding countermeasures to deal with.If the heat exchanger leakage, the general heat exchanger has the sound of water hammer, and condensate water increased, steam stop condensate discharge more than, this situation should be disassembled heat exchanger repair.
