Heat exchangers are widely used in industries such as air conditioners, power plants, refineries and internal combustion engines. You may not know that you are very familiar with heat exchangers. Like the radiator in your car. The heat exchanger keeps the equipment cool and prevents overheating from causing malfunctions. You may have seen someone open the hood of a car on the side of the road and emit smoke. This is the result of a malfunction of the radiator.

There are various heat exchangers on the market and the applications are also different. Shell and tube heat exchanger is a kind of widely used. Common in power plants, hydro, oil refineries and chemical processing plants. The basic structure consists of a large tube (shell) with many small tubes wrapped inside the middle. The liquid is different in the shell and in the tubule. The two liquids transfer heat between each other through the tube wall.

Shell-and-tube heat exchangers have high requirements for internal tube bundles. The tube needs good thermal conductivity and must also be used for a long time at high temperature and high pressure.

1. PTFE tube used in heat exchanger

PTFE tube has excellent corrosion resistance and almost all chemicals remain inert. Temperature resistance up to 260 ℃. It is an excellent inner tube for heat exchanger components.

Disadvantages:

(1) bonding problems. It is difficult to bond the PTFE tube and the sealing plate. Due to the non-tackiness of PTFE, it must be chemically treated and then bonded with an adhesive. However, the adhesive is easy to loosen under high temperature or other chemical liquid corrosion.

(2) welding problems. Special modified PTFE must be used to weld PTFE tubes, and the welding technology is very demanding.

(3) wall thickness and thermal conductivity contradiction. The heat exchanger must withstand the pressure generated by the fluid flow. In the case of higher pressure, the PTFE tube wall thickness must be thick enough to have a long service life. However, the thicker wall thickness PTFE tube has poor thermal conductivity.

2. FEP tube used in heat exchanger

FEP tube corrosion resistance is also very superior. The tube wall is smooth, high light transmission, easy to weld, instead of PTFE tube used in heat exchanger is an option.

Disadvantages: FEP tube chemical inertness is slightly lower than PTFE tube, temperature resistance up to 200 ℃, lower than PTFE260 ℃

3. PFA tube used in heat exchanger

PFA tubes combine the advantages of PTFE tubes and FEP tubes and are an excellent choice for heat exchanger tubes. Inherited the strong corrosion resistance of PTFE, high temperature up to 260 ℃, also adhering to the FEP high permeability, smooth, easy welding characteristics. High purity PFA tube can also be used in medical, food, semiconductor and other industries heat exchanger tube.

Disadvantages: expensive, raw materials rely on imports