Definition

Shell and tube heat exchanger is a wall heat exchanger with the wall surface of the tube bundle enclosed in the shell as the heat transfer surface. This heat exchanger is simple in structure, reliable in operation, generally made of ordinary carbon steel, copper or stainless steel, can be used at high temperature and high pressure, and is the most widely used heat exchanger in chemical and alcohol production.

STRUCTURE

Shell and tube heat exchanger is composed of shell, heat transfer tube bundle (heat exchange tube), tube plate, head, baffle plate (baffle) and tube box and other components. The shell is mostly cylindrical, and the tube bundle is arranged inside, and the two ends of the tube bundle are fixed on the tube plate. Its structure is characterized by a certain number of pipes around a water tank to form a tube bundle. The two ends of the pipe are connected through a tube plate, one tube head is connected to the heat source, and the other tube head is connected to the cooling medium. The water tank is divided into two parts, the upper and the lower, and the heat is exchanged through the coil. Under certain working conditions, different heat transfer effects can be achieved by adjusting the number and shape of the bundle.

Working principle

The working principle of the tubular heat exchanger is to use the fluid between the shell pass and the tube pass for heat transfer. The heat source flows into the heat exchanger through the tube, the fluid flows in the tube, is heated or cooled, and the heat is transferred to another fluid in the shell. This tubular design enables efficient heat transfer between the two fluids.

When heat transfer is carried out, a fluid enters the connecting pipe of the head, flows in the pipe, and flows out of the outlet pipe at the other end of the head, which is called the pipe path; Another fluid enters through the nozzle of the shell and flows out from another nozzle on the shell, which is called the shell path.
The cold and hot fluids for heat transfer, one of which flows in the tube, are called tube flow; The other flows outside the tube, called shell flow.

In order to improve the heat transfer coefficient of the fluid outside the tube, a number of baffles are usually installed in the shell. The baffle can increase the velocity of the shell fluid, force the fluid to pass through the tube bundle several times according to the specified path, and enhance the degree of fluid turbulence. The heat exchange tubes can be arranged in equilateral triangles or squares on the tube plate. The equilateral triangle arrangement is compact, the fluid turbulence outside the tube is high, and the heat transfer coefficient is large. The square arrangement is convenient for cleaning outside the tube and is suitable for fluids that are easy to scale. Each time a fluid passes through a tube bundle is called a tube pass; Each pass through the shell is called a shell pass. In order to increase the fluid velocity in the pipe, partitions can be arranged in the pipe boxes at both ends to divide all the pipes into several groups. In this way, the fluid only passes through part of the pipe at a time, and therefore goes back and forth many times in the tube bundle, which is called multi-pipe. Similarly, in order to increase the flow rate outside the tube, a longitudinal baffle can also be installed in the housing to force the fluid through the housing space several times, known as multiple shell passes. Multi-pass and multi-shell pass can be used together.

Product feature

(1) Good heat transfer performance;
(2) Strong self-cleaning ability, not easy to pollute;
(3) Small heat loss;
(4) The heat transfer temperature difference is small, and the temperature can be accurately controlled;
(5) small temperature difference stress;

(6) Compact structure;

Product Parameter

1、Material choice: carbon steel, copper or stainless steel

2、Type: 

① fixed tube-sheet heat exchanger

②floating heat exchanger
③U-tube heat exchanger
④stuffing box  heat exchanger

3、Technical parameter:

Manufacturing process

Application area

Tubular heat exchanger is a common heat exchange equipment, widely used in chemical, petroleum, food, pharmaceutical and other fields. First, in the chemical industry, it can be used in processes such as condensation, evaporation, heating and distillation. Secondly, in the petroleum industry, it is often used in catalytic cracking, reforming, hydrogenation and reforming processes. In addition, in the food and pharmaceutical industry, tubular heat exchangers are also widely used in food processing, pharmaceutical intermediate production and bioengineering pharmaceutical processes.