Bellows Expansion Joints

 

 

 

Parameter item	Examples of common values
Nominal Diameter (DN)	DN50 - DN3000(Non-standard dimensions can be manufactured according to drawings.)
Design Pressure (PN)	PN10, PN16, PN25, PN40
Design Temperature	-196°C to +800°C
Bellows Material	SS304, SS316L, Inconel 625
Connection Type	Flange , Welding
Movement Capacity	Axial, Lateral, Angular (mm/°)
Fatigue Life	1000, 3000, 5000 Cycles

 

 

 

 

"Axial Bellows Expansion Joint"(Axial type)

"Universal Expansion Bellows" (General/Multi-purpose)
"Tied Expansion Joint"  (Tie-Rod Type - Commonly Used in Southeast Asian Pump Rooms)
"Hinged Bellows Joint"  (Hinge Type)
"Gimbal Expansion Joint"  (Universal Joint Type)
"Pressure Balanced Expansion Joint"  (Pressure-Balanced Type - High-Cost Product)
"Externally Pressurized Bellows"  (External Pressure Type)

 

 

1. Fatigue Life Design (Fatigue Life / Cycle Life)

• Cycle life calculations compliant with EJMA (Expansion Joint Manufacturers Association) standards (1000-5000 cycles).

 

2. Material Integrity and Stress Corrosion Resistance

• Reliability assurance: We provide traceability and testing for raw materials.

• Common materials include: SS304, SS316L, SS321, Inconel 625, or Hastelloy and other high-performance alloys.

 

3. Multi-ply Construction

For high-pressure or complex conditions, multi-ply construction offers greater reliability than single-ply. This structure provides superior pressure-bearing capacity and flexibility with safety redundancy. If the inner layer perforates, the outer layer maintains system pressure temporarily while enabling timely detection via the tell-tale hole.

 

4. Welding Process & Non-Destructive Testing (NDT)

Welding quality directly determines whether expansion joints will experience "bursting." Our welders possess robust welding qualifications, and we perform 100% non-destructive testing (RT (Radiographic Testing), PT (Penetrant Testing)).

• Each product undergoes a hydrostatic test at 1.5 times the design pressure before shipment.

 

5. Structural Stability Design (Squirm & Stability)

Prevents "column buckling" or "plane buckling" of the bellows under pressure.

• Reliability is ensured through:

- Properly designed inner sleeve and external cover

- Anti-squirm design

- Prevention of resonance caused by media erosion.

 

 

1. Power Generation

• Turbine exhaust piping, boiler coal powder delivery piping, district heating circulation water systems.

• Product Features: Large diameter, high pressure, accommodates multidirectional displacement.

 

 

• 2. Refinery & Petrochemical

• Specific Applications: Fluid Catalytic Cracking Unit (FCCU), Heat Exchanger Tubing, Oil Transfer Pipelines.

• Product Features: Exceptional Corrosion Resistance (Inconel 625 / Hastelloy), High Pressure Resistance.

 

3. District Heating & HVAC

• Specific Applications: Steam mains, commercial building central air conditioning water systems.

• Product Features: Emphasis on fatigue life, accommodates axial expansion.

 

4. Steel Mills & Metallurgical

• Specific Scenarios: Hot blast stove ducts in blast furnaces, coking systems, dust removal flues.

• Product Features: For the extreme 1000°C environments mentioned, rectangular compensators or ceramic fiber linings are typically used.

 

5. Water Treatment & Pump Stations

• Specific Scenarios: Pump outlets, vibration-damping flexible connections, long-distance water supply pipelines.

• Product Features: Tied Expansion Joints are commonly used to constrain pressure thrust and protect pump bodies.

 

 

Choose Tianshun for precision engineering solutions that safeguard your pipeline projects. Let's join hands to shape the future of industrial fluid transportation.