Shell & Plate Heat Exchanger Advantages Technical Article

Product catalog summary

Introduction
Stefan Gavelin from Tranter International AB discusses the advantages of shell and plate heat exchangers over traditional designs, particularly in the hydrocarbon industry. These exchangers offer improved reliability and efficiency compared to traditional welded plate heat exchangers.

Advantages of Shell and Plate Heat Exchangers

Higher efficiency and compact size compared to shell and tube units.
Reduced maintenance needs due to less frequent cleaning requirements.
Cost-effective when using exotic materials due to lower heat transfer area requirements.
Superior resistance to thermal and pressure fatigue, making them suitable for dynamic processes.

Design and Performance
The shell and plate design eliminates the weak corner welds found in traditional designs, enhancing fatigue resistance. Circular plates are preferred over rectangular ones for better fatigue resistance. These exchangers can handle challenging conditions with liquids, gases, steam, and two-phase mixtures.

Fatigue Resistance and Testing
Fatigue failure is a major cause of metal failures. Shell and plate exchangers are designed to minimize stress concentrations, reducing the risk of fatigue failure. They can withstand significant temperature fluctuations and pressure cycles, although specific cycle data is proprietary.

Maintenance and Cleaning
The shell and plate design allows for full maintainability with removable plate packs. Chemical cleaning is often sufficient, but mechanical cleaning can be used if necessary. However, heavy fouling may require different exchanger types.

Applications

Overhead condensers in refineries for heat recovery.
Thermosyphon reboilers in gas sweetening processes.
Gas compression processes, especially offshore where space and weight are limited.

Conclusion
Shell and plate heat exchangers offer higher reliability and availability, making them a suitable replacement for older designs. Despite their advantages, conservative attitudes among process licensors remain a challenge.

Key Advantages

Compact size and higher heat transfer efficiency.
Reduced fouling due to turbulent flow.
Small temperature approaches for better heat recovery.
Easy maintenance with removable plate packs.
Elimination of critical corner welds found in other designs.

Catalog excerpts

Shell & Plate Heat Exchanger Advantages Technical Article-1

Stefan Gavelin, Tranter International AB, Sweden, explains the advantages of using shell and plate heat exchangers over other designs. Shell and plate, worth the wait P late heat exchangers have been used for many years in the hydrocarbon industry. The advantages of plate heat exchangers became more apparent with the introduction of the gasket free all welded plate heat exchangers in the early 1990s. However, the traditional all welded heat exchangers with square/rectangular plates (the four corner grid design) suffer from thermal and pressure fatigue due to the weak corner welds that often fail in dynamic processes, which results in unexpected shutdown and maintenance. Therefore, this design should be replaced by more reliable shell and plate heat exchangers in order to improve reliability and availability. The benefits of using plate heat exchangers are well known. They are more efficient, occupy less space, are lighter and do not need to be cleaned as often as shell and tube heat exchangers. When the material is exotic (high cost), the cost is less than for traditional shell and tube heat exchangers due to lower heat transfer area requirements; therefore, costs are reduced where corrosive fluids are present. The traditional welded plate heat exchangers available are of the four corner grid design and are manufactured Reprinted from September2009 HydrocarbonEngineering

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Shell & Plate Heat Exchanger Advantages Technical Article-2

from either rectangular or square plates. These plates have sharp corner welds that, from a fatigue point of view, are catastrophic and insidious as the welds can fail without warning. Shell and plate design The shell and plate heat exchanger is a highly efficient, reliable compact plate heat exchanger. Despite the excellent performance in both stable and dynamic processes, many engineers are questioning the performance due to lack of product knowledge and operating experience. Many engineers are reluctant to try them without a great deal of support in terms of process references and actual recommendations...

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Shell & Plate Heat Exchanger Advantages Technical Article-3

the test specimen to use for testing. This is not practical for a welded plate heat exchanger as the tests must show the actual resistance for the whole assembly and not the metal or a single weld joint for the metal. Normally, the fatigue test experimental test rig is designed to simulate actual operation (one of many samples). Essentially what is tested is the ability to withstand thermal mechanical fluctuations as experienced in the field, and to locate the weak point in the heat exchanger assembly and identify the mode of failure. suited for the application. It should also be mentioned that...

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