Shell & Tube Heat Exchanger Piping: A brief Presentation

Shell & Tube Heat Exchangers are the most frequently used Heat Exchangers in Process Plants. The purpose of this presentation is to provide guidelines for Shell & Tube Heat Exchanger Piping Layout. Click here to get a preliminary idea about shell and tube heat exchangers.

Use of Shell & Tube Heat Exchangers

All Heat exchangers are used to transfer heat from one fluid to another.

They are generally named as cooler, chiller, condenser, heater, reboiler, waste heat boiler, steam generator & vaporizer in the process plant.

Types of Heat exchangers

The most commonly used types of  heat exchangers are

• Shell & Tube heat exchanger
• Air-cooled heat exchanger
• Plate type heat exchanger
• Spiral heat exchanger
• Double pipe heat exchanger

Shell & Tube Heat Exchanger Construction (Fig. 1)

These heat exchangers are generally designed, fabricated, inspected and tested as per API 660 / EN-ISO 16812 / TEMA. The DEP for the design & construction of the shell & tube heat exchanger is DEP 31.21.01.30 – Gen.

General Guidelines for selection for tube side & shell side fluids:

• Clean fluid through shell & dirty fluid through tubes
• Corrosive fluid through tubes as it is easy for cleaning & allows the use of carbon steel for shell
• Water through shell & process liquid through Only seawater through the tube side
• High-pressure fluid through tubes which allows for min. the wall thickness of the shell

The layout of shell & tube heat exchangers other than in banks

As per the exchanger positions in a process plant the following general classification can be made:

1. Exchangers which should be next to other equipment: e. g. Vertical Reboiler
2. Exchangers which should be close to other equipment: e. g. Overhead condenser
3. Exchangers located between other process equipment: e. g. The exchanger with process lines connected to both shell & tube side
4. Exchangers located between process equipment and the unit limit:e.g. Product coolers

Establishing elevations for the exchanger

• Where process requirement dictates the elevation, it is usually noted on the PEFS
• The grade is the best elevation from an economic point of view
• Located in structures where gravity flow is required or connected to pumps suction which has specific NPSH requirement e.g. overhead condenser

Layout of Shell & Tube heat exchanger in banks

Arrangement of exchangers (Fig. 2):

Various types of Exchanger orientation is possible as mentioned below:

Sample exchanger orientation (Fig. 3)

Single and Paired Exchangers (Fig. 4)

Parallel Exchanger Installation (Fig. 5)

Series Exchanger Installation (Fig. 6)

Stacked exchanger installation

Two exchangers in series or parallel are usually stacked. Refer Fig. 7

Nozzle arrangement for better piping (Fig. 8)

Structure mounted exchanger installation (Fig. 9)

Supporting of shell & tube heat exchanger piping

• No special guideline for supporting
• Stress analysis required to be carried out for the exchanger inlet & outlet lines
• Fixed saddle-support near the tube bundle head, sliding support near the rear head

Heat exchanger maintenance

Tube bundle extractors (Fig. 10)

Few more resources for You..

Basics of Shell and Tube Heat Exchangers: A brief presentation
An article on Plate Heat Exchanger with Steam
A typical Check List for Reviewing of Shell & Tube Heat Exchanger Drawings
A brief presentation on Air Cooled Heat Exchangers
Basic Considerations for Equipment and Piping Layout of Air Cooled Heat Exchanger Piping
Reboiler Exchanger and System Type Selection