Transfer of second-hand tube heat exchanger

Transfer of second-hand tube heat exchanger

Company Introduction

Liangshan County DeDe Second hand Equipment Purchase and Sales Department provides long-term supply of second-hand drying equipment, second-hand domestically imported disc separators, second-hand heat-conducting oil furnaces, second-hand horizontal spiral centrifuges, second-hand plate and frame filter presses, second-hand horizontal scraper centrifuges, and second-hand horizontal two-stage piston pushing centrifuges Used bundle dryer, used flash dryer, used enamel reaction kettle, used stainless steel reaction kettle, used stainless steel tube condenser, etc., used stainless steel cold and hot cylinders, used high-pressure homogenizer, used dairy equipment, used beverage equipment, edible oil processing plant, feed processing plant, alcohol plant, dairy plant, food protein plant, beverage plant complete set of production equipment

dehangershouhuagongshebei-miaoyuanyuan

Transfer of second-hand tube heat exchanger

1、 Basic Structure and Composition

Shell (Shell)

A cylindrical shell that accommodates the tube bundle inside, typically made of carbon steel, stainless steel, or special alloys.

The two ends of the shell are connected to the pipe plate through flanges or welding.

Tube Bundle

Multiple parallel arranged metal tubes (made of materials such as copper, titanium, stainless steel, etc.) are fixed at both ends on the tube plate.

Tube bundle design forms: straight tube, U-shaped tube, spiral tube, etc.

Tube Sheet

A thick plate with a fixed tube bundle, sealed and connected to the shell, separating the fluid in the shell and tube sides.

Baffles

Installed inside the shell, it guides the fluid to laterally flush the tube bundle, enhances turbulence, and improves heat transfer efficiency.

Head/End Cap

Distribute or collect tubing fluid, divided into fixed end and detachable end (for easy cleaning).

2、 Working principle

Heat transfer method: High temperature fluid (shell side or tube side) conducts heat to low-temperature fluid through the tube wall, achieving heat exchange.

Flow mode:

Counterflow: Cold and hot fluids flow in the opposite direction.

Parallel Flow: Flow in the same direction with gradually decreasing temperature difference.

Crossflow: Flow direction perpendicular to each other, commonly seen in gas-liquid heat transfer.

3、 Classification and Characteristics

Fixed tube plate

The structure is simple and the cost is low, but when the thermal expansion of the tube bundle and the shell is inconsistent, stress is easily generated, and expansion joints need to be added.

Applicable scenarios: working conditions with small temperature differences and low pressure.

Floating head style

One end of the tube plate can float to compensate for thermal expansion, making it easy to disassemble and clean the tube bundle.

Applicable scenarios: high temperature, high pressure, or fluids prone to scaling.

U-shaped tube type

The tube bundle is U-shaped, with a flexible free end and strong heat stress resistance, but it is difficult to clean inside the tube.

Applicable scenarios: fluids with high temperature, high pressure, and high cleanliness (such as steam).

4、 Key parameters for selection and design

Fluid properties

Corrosivity, viscosity, and tendency towards dirt (affecting material selection and cleaning frequency).

operating conditions

Temperature range, pressure, flow rate (determining the thickness and structure of the shell and tube bundle).

Heat transfer calculation

Logarithmic mean temperature difference (LMTD), total heat transfer coefficient (U value), and heat load (Q).

Pressure drop control

The pressure drop of the shell and tube sides must meet the process requirements and avoid excessive energy consumption.