Expansion Joints for Shell & Tube Heat Exchangers
The design, engineering, manufacturing, and testing of expansion joints for Shell & Tube Heat Exchangers and other static equipment require detailed attention to several critical aspects Unlike standard piping systems, these heat transfer units operate in multiple modes, and their operating parameters vary significantly. As a result, expansion joints used in these applications must be carefully engineered to suit these varying conditions.
Purpose & Performance Requirements
Expansion joints are essential for compensating differential thermal expansion between the shell and tube bundle. These joints must function effectively under diverse conditions and ensure long-term performance. Due to the minimal clearance between the shell and baffles, the expansion joint on the shell side must allow the tube bundle to slide through without obstruction
MEJ for methanol convertor application
Expertise in Design and Engineering
LSI – Mech Engineers Private Limited has decades of experience in overcoming these technical challenges across all stages of product realization. Our engineers possess deep Knowledge in relevant codes and standards, metallurgy, welding techniques, and heat treatment processes. We specialize in the design and manufacturing of both thin-walled (<3mm) and thick-walled expansion joints for fixed tube sheet and floating head heat exchangers.
Proven Track Record
With a global footprint, we have successfully supplied over 600 expansion joints for Shell & Tube Heat Exchangers, many of which have been in operation for decades. Our attention to detail and stringent adherence to dimensional tolerances ensures high-quality output in every project.
MEJ for CRR platform reactors applications
Manufacturing and Welding Considerations
Manufacturing of these components demands precision and strict quality control.Welding bellows to shells made of Cr-Mo steel, for example, requires specialized procedures to prevent weld failures. Our experienced welding engineers ensure the process meets the required standards.
High-Pressure Testing for Reliability
Since many process industry heat exchangers operate at high to very high pressures, expansion joints must be reliably pressure-tested in the shop before delivery. This is a critical step in assuring long-term joint integrity.
MEJ for Fixed tube sheet Heat Exchanger application (Size ID:850 ND)
Tube Side and Floating Head Considerations
Expansion joints on the tube side or in floating head arrangements are exposed to the operating conditions of both shell and tube, creating dual stresses. These components must be designed to withstand very high external pressures, all while maintaining a compact footprint to ensure overall equipment economy.
MEJ for Floating Head Heat Exchanger applications
Expansion Joint located in Floating Header side
Materials: Common materials used for bellows include stainless steel, Cr,Mo alloy steel, and Inconel, chosen based on the operating conditions and required durability. Proper selection and design of expansion joints rely on understanding the application conditions.
This includes:
• Design cases for operating, start-up, shut-down, and upset.
• Mean-metal temperatures of tubes and shell for these cases
• Metallurgy of tubes and shell
• Calculated thermal movements for each design case.
• Expected thermal cycles during exchanges lifetime.
• Design pressures and temperatures
• Applicable codes and standards
LSI-MECH will utilize this data to design an appropriate expansion joint style and materials of construction. Provisions for shipping, assembly, and hydro test supports may also be needed. Anticipating the full range of operating conditions, including transients, is critical to ensure the expansion joints perform reliably.
MEJ for Fixed tube sheet Heat Exchanger application
LSI-MECH quality program has been certified by ASME and bears the ASME Single certification mark with the ‘‘U” designator for pressure vessels as per Section viii Division 1 and ASME Single certification mark with the ‘‘U2” designator for pressure vessels as per Section viii Division 2. Additionally we also have IBR, PED (Pressure Equipment Directive) , NB stamp and EIL approvals. If design temperature of bellows above the time dependent behavior [creep and fatigue interaction] of the material shall be designed using methods like Finite Element Analysis. Adequate knowledge on codes / standards, material, welding engineering, heat treatment practices etc., assure to meet all requirements. Our track record on supply exceeds 600 Expansion Joints for Shell & Tube Heat Exchangers, installed worldwide and satisfactorily functioning for decades together.
