Do You Know How to Avoid Leaks in Shell and Tube Heat Exchangers?

Leaks occur when they cause a reduction in feedwater pressure and a reduction in the amount of feedwater sent to the boiler. Therefore, the discovery of shell and tube heat exchanger tube system leaks immediately stop the heat exchanger to reduce the number of damaged tubes and reduce the degree of damage. When the unit is shut down, you should check whether the high plus leaks and find ways to eliminate them. The following are several preventive measures for shell and tube heat exchanger leaks.

Here is the content list:

• Scouring erosion preventive measures

• Tube vibration preventive measures

• Erosion prevention measures at the inlet end of the tube feedwater

• Corrosion prevention measures

Scouring erosion preventive measures

Restrict the flow rate of shell-side steam or hydrophobic and prevent flash steam in the evacuation section. Steam cooling section of the exit steam to have sufficient residual superheat. The flushing plate should be fixed firmly, with sufficient area and good material. Keep the shell side water level normal, and prohibit low or no water level operation. All of the above are preventive measures to avoid flushing erosion of shell and tube heat exchangers.

Tube vibration preventive measures

Install vapor-side safety gates on the high-addition steam side. Limit the flow rate of steam or hydrophobia on the shell side. The tube spacing should be large enough, which on the one hand reduces the shell-side flow rate, and on the other hand, reduces the possibility of tube collision and friction damage to each other. Limit the length of the free section of the tube bundle. Only the elimination of tube vibration can ensure the safe operation of shell and tube heat exchangers.

Erosion prevention measures at the inlet end of the tube feedwater

The fluid flow rate in the tube process or tube process, not only affects the value of the convective heat transfer coefficient but also affects the fouling thermal resistance, thus affecting the size of the total heat transfer coefficient. Therefore, it is important to choose the appropriate flow rate. Limit the feed water flow rate, stop using a heat exchanger or heat exchanger blocking the number of more, will make the tube flow rate increase significantly, then part of the feed water should be allowed to bypass into the boiler or reduce the unit load. These can be avoided by shell and tube heat exchanger feed pipe mouth erosion.

Corrosion prevention measures

Stress relief. Stress can have various sources, such as applied stress, residual stress, welding stress, and stress from corrosion products. Materials are selected so that the unit becomes a copper-free system, which is beneficial to the corrosion prevention and vapor crystal quality control of the entire unit. To have a perfect air release system. To ensure the normal work of the air release system, in the start-up, the waterside, and steam side should be purged of air and the feed water quality to qualified. Only to ensure that the water quality is qualified, in order to eliminate the occurrence of shell and tube heat exchanger corrosion from the root.

There is no equipment that does not fail. Failure occurs, and we will go to solve the failure. These are several shell and tube heat exchanger leakage prevention and treatment measures. I hope that the use of heat exchangers can be helpful.