Types of Shell and tube heat exchangers

Shell and tube heat exchangers are one of the most popular types of heat exchangers because of their flexibility to accommodate a wide range of temperatures and pressures. These heat exchangers have long been the choice by industrial and commercial personnel and with high popularity among these individuals comes a variety of shell and tube heat exchanger types.

Though the standard construction of a shell and tube heat exchanger is simple in the design there are different varieties, materials, and configurations to suit a multitude of industry needs. The standard construction of a shell and tube heat exchanger consists of the following:

1. Shell, or pressure vessel – is where a cooling or heating fluid will flow through to transfer heat or remove heat from a tube bundle.
2. Tube bundle – The bundle is inserted into the pressure vessel and the process fluid is run through for heating or cooling purposes.
3. Tube Sheet – The tube sheet is used to support and isolate the tubes within a shell and tube heat exchanger.
4. Baffles – Baffles are plates that direct shell fluid flows around the tube bundle to promote heat transfer.

Each industry and individual need will be different and thus leads to a different style of shell and tube heat exchanger.

• Fixed Tubesheet – this heat exchanger type has straight tubes through the shell and are fixed at both ends.
• U-Tube – as the name describes, the tube bundle in this heat exchanger is U-shaped. The tubes start in the top part of the tube sheet, make a U, and come back to the bottom part of the tube sheet.
• Floating Head – This heat exchanger type has one end of the tube fixed in the tube sheet while the other end is kept free to expand.

Every process need will be different and thus have a different need for their heat exchanger materials of construction. This is dependent upon the fluids, pressures, and temperatures used within the heat exchanger. Examples of the more common materials of construction are listed below:

Shell Materials

• Carbon Steel (The most common)
• Stainless Steel (Typically 304 or 316)
• Cast Iron
• Titanium

Tube materials

• Copper
• Stainless Steel
• Titanium
• Hastelloy
• Fluoropolymer (FEP, PFA, and “Q” resins) “Q” is a special fluorocarbon compound that significantly improves thermal efficiency and increases temperature and pressure capabilities. This material is available exclusively through Ametek Fluoropolymer Products.

Shell and tube heat exchangers come in a variety of styles and materials to help each customer achieve their heat transfer goals.