BEST-IN-CLASS

LENS EXPANSION JOINTS

Lens Expansion Joints are the custom requirements in cases where the application requires a single layer bellow. If the material thickness of the single layer bellow is more than 4 mm, the supply of a normally manufactured bellow is no longer possible. In this case, Lens Expansion Joints are the optimum solution. Normally issues concerning material thickness are solved by the supply of a multilayer bellow but in some cases, this is not accepted by the customer and/or the application.

Design range within Lens Expansion Joints

Belman Lens Expansion Joints can be designed within the range:

DIMENSIONS:
Diameter: up to DN 2500
Larger dimensions can be
discussed on request

RADIUS:
Radius (R): 15, 20, 30, 50, 60 and 80 mm
1,5 mm: Max. R =15
2+3 mm: Max. R =30
4+5 mm: Max. R =60
6+8 mm: Max. R = 80

DESIGN CODES:
EJMA, EN 14917,
ASME or AD2000

CUSTOMISED

LENS EXPANSION JOINTS

LENS EXPANSION JOINTS

TECHNICAL DESCRIPTION

APPLICATIONS

Typically Lens Expansion Joints are used in heat exchangers and very often in steel plants.

CONSTRUCTION

Lens Expansion Joints are constructed as illustrated on the drawings below.
As it is shown, Lens Expansion Joints are supplied either as a half convolution, a complete convolution or as a bellow. According to the customer’s requirements, these are either delivered already welded together or they can be welded together on-site.

Half convolution of a Lens Expansion Joint

Illustation of two half convolution lens

Convolution from two half convolutions welded together.
The black triangle illustrates the welding.

Bellow from two convolutions welded together from four half convolutions.
The black triangles illustrate the weldings

ADVANTAGES

What are the advantages of using Lens Expansion Joint?

Lens Expansion Joints are preferred in all industries that uses pressurised equipment and heat exchangers and where the higher pressure and higher temperature require greater material thickness.

QUALITY & TESTS

Belman is known for high quality products and therefore our quality control is a fundamental part of our business. All processes during production designed by the Belman quality engineers, is strictly follow and implement according our procedures and instructions and carefully inspected by Belman quality inspectors. All checks and inspections are done according to the strict prevailing Belman quality control procedures which is part of the Belman ISO 9001 quality management system approved by DNV.

ITP & Test
Inspection test Plan generated by the quality management system makes sure that each step of manufacturing has the appropriate inspection points such as Hold and Witness points.

Based on manufacturing code, project specification, application, media, and eventual ship classification rules Belman performs a large variety of quality tests including destructive, non-destructive testing and proof testing. All tests can be witnessed by the 3^rd part based on the customer and classification requirements.

Destructive test: such as life cycle test and burst test to validate the design, i.e., vessels and offshore platforms
Non-destructive test such as Visual testing, dye penetrant test, Radiography examination, Magnetic testing, ultrasonic testing, hardness testing and PMI for all applications
Proof tests: leak test with air, leak test with helium and “formier” gas, hydrostatic pressure test for all application

Belman QC and tests

EXPERIENCED & APPROVED SUPPLIER

REFERENCES

Vattenfall • Saline Water Conversion Cooporation (SWCC) • Rosneft • RWE • Gryaab • Air Liquid • MOL • Yamal LNG • Siemens • Equinor (statoil) • Phosagro • OCI • Wärtsilä

Shell • HEP • Linde Gas • PGNIG Termika • SSAB • KenGen • Stora Enso Paper • GE Power • Ineos • SABIC • Lukoil • BP • Nornickel • TATA • Bagfas • ThyssenKrupp

See more references

WE HAVE ENGINEERED

EXPANSION JOINTS SINCE 1994

This enable us to find you the optimum solution to your piping system.