High Pressure Lens Type Metal Expansion Joint for Heat Exchanger

Product Description

Product Description

Overview of Lens Type Expansion Joint

Specifically engineered for Shell & Tube Heat Exchangers and Pressure Vessels, our Lens Type Expansion Joint offers a robust solution for thermal expansion. Unlike standard thin-wall bellows, the Lens Joint is fabricated from thick-wall steel plates pressed into a rounded lens shape.
This design allows it to withstand high internal pressures and harsh operating conditions where standard expansion joints would fail. It is the critical component to release thermal stress between the shell and tubes of your heat exchanger.

Key Features

1. High Pressure Resistance: Manufactured from thick carbon steel or stainless steel plates (6mm - 20mm+), ensuring high structural integrity.
2. Low Stress Concentration: The smooth, rounded lens profile distributes stress evenly, extending the fatigue life.
3. Self-Draining & Easy Cleaning: The gentle wave shape prevents sediment accumulation and allows for complete drainage, ideal for chemical and sanitary applications.
4. Compact Design: Short installation length (axial length), saving valuable space in equipment design.

Product Details

Product Name	Lens Type Expansion Joint
Model	JD-Lens Series (Welded Type)
Size Range	DN300 - DN4000
Structure	Single Wave (Standard) or Multi-Wave
Wall Thickness	6mm, 8mm, 10mm, 12mm (Customizable)
Design Pressure	1.6 MPa - 6.4 MPa (High Pressure)
Material	Carbon Steel (Q235B / Q345R), Stainless Steel (304/316L)
Connection	Butt-Weld Ends (Beveled for welding)
Design Standard	ASME Section VIII Div. 1, TEMA, GB/T 16749
Compensation	Axial Movement Only
Application	Heat Exchanger Shell, Boiler, Reaction Kettle
Customization	Available
Certificate	ISO 9001, Material Test Certificate (MTC)
HS Code	8307100000

Specification

1. Price Basis:
The prices listed above (e.g., DN600 @ $480) are estimated based on Standard Carbon Steel (Q235B/Q345R) with a standard wall thickness.
Real price depends on weight. Since Lens Joints are made of thick steel plates, the cost is calculated based on the specific Wall Thickness (6mm-20mm) and Total Weight.
2. Material Selection:
Standard: Carbon Steel is the most common choice for Heat Exchanger shells.
Upgrade: Stainless Steel (304/316L) is available but costs significantly more. Please specify the material in your inquiry.
3. Customization Required:
This is strictly a Made-to-Order product.
Please send us your technical drawing or sketch (including Diameter, Thickness, and Wave Height) for an accurate quotation.

Specification	Price
DN300	$180
DN600	$480
DN1000	$1100
Customization	Negotiable

Application

Shell & Tube Heat Exchangers

High-Pressure Reaction Kettles & Vessels

Long-Distance High-Pressure Gas/Steam Pipelines

The primary application for Lens Joints is on the shell of Fixed Tubesheet Heat Exchangers.
During operation, the shell and the internal tube bundle expand at different rates due to temperature differences. Without compensation, this stress can crack the tubesheet or pull the tubes out. 

The Lens Expansion Joint is welded onto the shell. It compresses or stretches to absorb this differential thermal expansion, relieving stress and preventing equipment failure. It withstands much higher shell-side pressure than standard U-shape bellows.

Widely used in the Petrochemical and Chemical industries for large reaction kettles and storage tanks.
Chemical reactions often generate high heat and pressure inside the vessel, causing the vessel body to expand axially.
Installed on the vessel body, the thick-wall Lens Joint absorbs this expansion while maintaining structural integrity under high pressure (up to 6.4MPa).Its smooth, rounded internal profile prevents chemical residue buildup (dead zones) and allows for easy cleaning, which is critical for chemical processing.

Applied in large-diameter pipelines transporting high-pressure steam, natural gas, or oil.
Long straight pipes generate massive axial expansion forces when heated. Standard bellows might be too thin and fragile for high-pressure transmission.
The Lens Joint provides a robust, heavy-duty solution for axial compensation. Its geometry is naturally self-draining. Condensate (water) does not get trapped in the wave convolution, reducing the risk of corrosion and water hammer.

Production Showcase

Our Company

Company Profile

Shanghai Baori Steel Industries Co., Ltd, has established its significant 
presence in the metal manufacturing and fabrication industries. Since its 
establishment on Aug 03, 2023, the company has 
been committed to providing comprehensive and efficient 
fabrication solutions, focusing on the integration 
and optimization of steel supply services.

Company Address

Our company is located in Baoshan District, Shanghai, China.
Specific Location:

Room 403, Building 1, Lane 1588, Youyi Road, Baoshan District, Shanghai, China 

FAQ

Q: What is the main difference between a Lens Joint and a standard Bellows?
A: The Lens Joint is made of thick steel plates (pressed and welded), whereas standard bellows are made of thin metal sheets. Lens Joints are designed for higher pressure applications and offer better structural integrity for Heat Exchanger shells.

Q: How do I install the Lens Expansion Joint?
A: It is designed for Butt-Welding. The joint comes with beveled ends. You simply weld it directly onto the shell of the heat exchanger or pipeline.

Q: Do you follow any specific design standards?
A: Yes. We design and manufacture according to ASME Section VIII Div. 1 and TEMA standards. We can provide calculation sheets if required.

Q: How do you ensure the welding quality?
A: Safety is our priority. Every Lens Joint undergoes:
100% Visual & Dimensional Check.
100% Dye Penetrant Test (PT) on weld seams.
Radiographic Test (RT / X-Ray) (Optional upon request).
Hydrostatic Pressure Test before shipment.

Q: Can you produce multi-wave lens joints?
A: Yes. While single-wave is the most common, we can fabricate 2, 3, or more waves to absorb larger axial movements based on your calculation.