Axial metal bellows expansion joint
DN250.
Axial metal bellows expansion joint is a flexible pipe compensator with stainless steel bellows as the core pressure-bearing element, equipped with end pipes/flanges, optional inner sleeve and limit tie rods. It absorbs axial displacement caused by thermal expansion and contraction of pipelines through elastic compression and extension of bellows along the pipe axis. It can accommodate minor lateral and angular offset from installation error, but shall not be used for major transverse or angular movement. Compact in structure, available in internal pressure and external pressure types, connected by flange or butt weld. Widely used in straight pipe sections of thermal power, chemical and power systems. Fixed anchors and guide supports are mandatory to absorb pressure thrust and prevent bellows instability.
Delivery
EXW
minimum order
10 pieces
Supply Ability
100pieces / Day
Country of Origin
CHINA
Stock Time
7Day
Quantity:
US $19.00 - US $1999.00 / pieces
1. Product Overview
The axial metal bellows expansion joint is a specialized flexible piping component designed for thermal displacement compensation in industrial pipeline systems. Taking high-quality stainless steel bellows as the core elastic pressure-bearing element, the product is assembled with end pipes, flanges, guide sleeves and limit components. It is professionally applicable to absorb and compensate the axial thermal expansion and contraction displacement generated by temperature changes of medium and pipeline. With compact structure, excellent pressure resistance and fatigue resistance, it is widely adopted in thermal power, chemical industry, petroleum, heating, metallurgy and municipal pipeline engineering. This product is manufactured and tested in strict accordance with GB/T 12777 standard.
2. Structural Composition
The complete axial metal bellows expansion joint consists of multiple functional components, ensuring safe operation and stable compensation performance:
- Bellows Body: Made of Austenitic stainless steel (common materials 304/316L/321), featuring high elasticity, corrosion resistance and anti-fatigue performance, serving as the key displacement compensation part.
- End Pipe & Flange: Connecting parts matched with on-site pipelines, supporting welding connection and flange connection to meet different installation requirements.
- Inner Guide Sleeve: Optional accessory, used to reduce medium scouring on the bellows, avoid turbulence, and improve the service life of the expansion joint.
- Limit Tie Rod: Auxiliary safety component, which can limit the maximum compensation stroke and bear blind plate thrust under abnormal working conditions to prevent equipment damage.
3. Core Technical Parameters
The main performance parameters of axial metal bellows expansion joint are standardized and customizable to adapt to different pipeline working conditions:
Parameter Item | Technical Specification |
|---|---|
Applicable Diameter Range | DN25 – DN4000 |
Nominal Pressure | PN0.6 – PN16 (customizable for high pressure) |
Working Temperature | -40℃ ~ 450℃ |
Main Compensation Mode | Axial displacement (tensile & compressive) |
Auxiliary Compensation Capacity | Minor lateral & angular displacement |
Execution Standard | GB/T 12777 |
4. Working Principle
When the industrial pipeline operates with temperature rise or drop, linear thermal deformation will occur. The flexible stainless steel bellows of the expansion joint realizes elastic telescopic deformation along the pipeline axis, which effectively absorbs the axial displacement of the pipeline. It offsets the thermal stress generated by pipeline expansion and contraction, avoids pipeline deformation, cracking or connection loosening caused by stress accumulation. Meanwhile, the product can weaken pipeline vibration and reduce noise transmission, improving the overall operation stability of the piping system.
5. Installation & Application Notes
- Support Configuration: Fixed anchor supports and guide supports must be equipped on the pipeline to bear medium pressure thrust and control the displacement direction, preventing bellows instability and distortion.
- Installation Scenario: It is only suitable for straight pipe sections, not for bending pipe sections or positions with severe lateral displacement.
- Pre-deformation: Professional pre-compression or pre-tension construction is required according to the actual working temperature to ensure optimal compensation effect.
- Restriction: Not applicable for bearing large lateral and angular displacement, which will cause bellows fatigue damage and reduce service life.
