In spiral-wound membrane systems, Anti-Telescoping Devices (ATDs), also commonly referred to as Interconnectors (ICs), along with Blank End Plugs (BEPs), play a critical role in ensuring structural integrity, correct flow distribution, and long-term plant reliability.
While these components may appear simple, correct material selection, profile matching and installation are essential to maintaining performance under pressure.
ATDs are designed to manage the axial load forces generated during operation. Under pressure, membranes are subjected to significant compressive forces. If not properly supported, this can result in membrane movement or “telescoping”, which may lead to performance loss or mechanical damage.
ATD/IC components are typically manufactured in either:
Material selection should be based on position within the pressure vessel and operating conditions.
Stainless steel ATDs are typically recommended on the permeate outlet end of the pressure vessel.
This location experiences the highest axial load forces generated by operating pressure. Stainless steel provides the mechanical strength required to:
Using non-metallic components in high-load positions may increase the risk of deformation or failure over time.
Provided the correct tools are used, PS ATD/IC components can be used to connect membranes in series throughout the membrane housing.
Polysulfone offers:
However, correct installation is essential. Poor alignment, excessive force, or incorrect tooling can lead to cracking, misalignment, or stress damage.
ATD/IC components include centre core profiles that must be matched with the correct lip seal.
These profiles are designed to suit both:
Permeate tube internal diameters typically range from:
Incorrect matching between ATD profile and lip seal can result in leakage, bypass or premature wear.
Material compatibility with CIP chemistry must also be considered.
In UF and MF plants where sodium hypochlorite (NaOCl) is used as part of the cleaning regime, SMS manufactures Viton lip seals designed to withstand repeated exposure.
EPDM seals may degrade over time when exposed to NaOCl, increasing the risk of seal failure.
Selecting the correct seal material should take into account:
ATDs and lip seals are engineered components designed to meet the mechanical and chemical requirements of the membrane system.
Correct material selection, profile matching and installation practices are critical to maintaining structural integrity and long-term reliability in spiral-wound systems.
For assistance with compatibility, refer to our Product Selection Guide or review the FAQs on our website, which includes common questions. If you are planning a membrane changeout or reviewing component compatibility, our team is available to help ensure your components are correctly matched to your membrane and application.
