1、 Tube bundle failure

1. Corrosion and wear of the tube bundle cause the leakage of the tube bundle or the fouling in the tube bundle, causing the blockage and causing the failure

The cooling water contains metal ions such as iron, calcium, magnesium and other metal ions, anions and organic substances. The active ions will enhance the corrosion of cooling water. The presence of metal ions causes depolarization of hydrogen or oxygen, which leads to tube bundle corrosion. At the same time, because of the ca2+, mg2+ ions in the cooling water, it is easy to scale and block the tube bundle for a long time.

In order to improve the heat transfer effect and prevent the tube bundle from corrosion or blockage, the following methods are adopted:

(1) Add scale inhibitor to cooling water and clean regularly.

For example, the cooling water of gas cooler is treated with ion electrostatic processor or added scale inhibitor and bactericidal and algal inhibitor to remove dirt and reduce the hardness of cooling water, thus reducing the scale degree of the tube bundle.

(2) Keep the flow rate of the fluid in the tube stable.

If the velocity increases, the thermal conductivity increases, but the wear will increase accordingly. The coal-based coal mine has carried out frequency conversion transformation of underground water pump, which makes the pressure of underground water pipe network more stable, improves the heat exchange effect of heat exchanger and reduces the corrosion of the tube bundle.

(3) Corrosion resistant materials (stainless steel, copper) or the way to increase the wall thickness of the tube bundle are selected.

(4) When the end of the pipe is worn, the protective tube bundle such as synthetic resin can be connected within 200mm of the inlet.

2. Vibration caused failure

The causes of vibration include:

Vibration of the tube bundle caused by the vibration of the pump and compressor; Pulsation caused by rotating machinery;

The impact of high-speed fluid (high pressure water, steam, etc.) into the tube bundle.

The following methods are often used to reduce the vibration of the tube bundle:

(1) Try to reduce the number of parking.

(2) At the entrance of the fluid, the adjustment groove is installed to reduce the vibration of the tube bundle.

(3) The spacing of baffle plate is reduced, and the amplitude of the tube bundle is reduced.

(4) Minimize the bore diameter of the tube bundle through the baffle plate.

2、 Flange leaking in

The leakage of flange is caused by the increase of temperature, the heating elongation of fastening bolts, and the gap in the fastening part.

Therefore, after the heat exchanger is put into use, the flange bolts need to be tightened again.

The fluid in the heat exchanger is mostly toxic, high pressure and high temperature substances. Once leakage occurs, it is easy to cause poisoning and fire accidents,

In daily work, special attention should be paid to the following points:

Minimize the number of gasket and use metal gasket;

The method of tightening gasket with internal pressure is adopted;

The operation method is easy to fasten.