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Maintenance
Tales from the field Over the years , Southeast Asia refineries has commissioned various types of high-pressure heat exchangers across its hydrocarbon processing facilities . Each deployment has provided valuable insights into operability and maintainability , underscoring the need for tailored designs that align with specific operational demands . One notable case involved a Feed and Reactor Effluent heat exchanger , which experienced recurring leaks shortly after its commissioning in 2021 . Despite rigorous testing and initial assurances of reliability , the system faced performance challenges worsened by unit upsets . The leaks were traced to the internal assembly responsible for sealing the tubesheet gasket — a critical component meant to withstand all operating conditions .
Complexities in high-pressure heat exchanger handling High-pressure heat exchangers are crucial yet highly complex components , particularly in the energy and chemical industries . Their design , operation , and maintenance pose significant challenges essential for ensuring reliability , safety , and efficiency in demanding conditions . In this article , we aim to highlight two critical challenges encountered with high-pressure heat exchangers , drawing from past operational experience which are : 1 . Loss of Bolt Load 2 . Difficulties in Disassembling which underscore significant hurdles that impact system performance , reliability , and maintenance efficiency .
Loss of bolt load due to stacked components and gasket relaxation One of the critical challenges identified with high-pressure heat exchangers is the loss of bolt load , which is intricately linked to the interplay of stacked components and gasket relaxation .
Overview high pressure heat exchanger .
In systems where multiple components — up to seven — are stacked on a single joint , the complexity of thermal behaviour becomes a significant concern . During thermal upsets , each component expands and contracts at different rates due to varying thermal coefficients . This mismatch creates a non-uniform response across the joint , introducing uneven stresses that gradually compromise the clamping force needed to sustain sealing integrity . The issue is further worsened when using a three-gasket system , which adds layers of variability to the joint ’ s behaviour under operational conditions . The three-gasket system , by itself is a system that is rarely being implemented in high-pressure heat exchangers even at the global scale . Nevertheless , one refinery in Malaysia integrated this system into a high-pressure heat exchanger as shown in Figure 2 , setting it apart from standard practices .
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Multiple parts compression and three-gasket system . www . heat-exchanger-world . com Heat Exchanger World February 2025
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