Expansion bellows

Locus Expansion Bellows are flexible connectors designed to absorb movement and vibration in piping systems.

Brand : LOCUS
Type : Rubber Expansion Bellows / Metallic Expansion Bellows
Material : EPDM, Neoprene, Nitrile, Silicone, SS304, SS316 (for metallic type)
Size Range : DN 25 to DN 1200
Pressure Rating : Up to 25 Bar
Temperature Range : -40°C to +180°C (Material Dependent)
Movement Type : Axial, Lateral, Angular
Design Standard : EJMA / ASTM F1123 / ASME B31.3
Customization : Available (Size, Flange Drilling, Reinforcement, etc.)
Applications : HVAC, Pipelines, Power Plants, Chemical, Marine, and Oil & Gas Industries
Certifications : ISO 9001:2015, CE Marking, ROHS, REACH, BIS (if required)
Country of Origin : India
Manufacturer : Locus International Exports (OEM/White-label Options Available)

Description

1. Description

Locus Expansion Bellows are flexible connectors designed to absorb movement and vibration in piping systems. Engineered from high-grade rubber or stainless steel, these bellows compensate for thermal expansion, misalignment, mechanical vibration, and pressure pulsations. Available in multiple sizes and configurations, they ensure durability, noise reduction, and extended pipeline life.

2. Specification

Parameter	Rubber Bellows	Metallic Bellows
Material	EPDM, NBR, Neoprene, Silicone	SS304, SS316, Inconel (on request)
Sizes	DN25 to DN1200	DN25 to DN1200
Pressure Rating	Up to 16 Bar	Up to 25 Bar
Temperature Range	-40°C to 120°C (Rubber Type Dependent)	-100°C to 500°C
End Connections	Flanged / Threaded / Weldable	Flanged / Weldable / Quick Coupling
Reinforcement	Nylon / Kevlar / Steel wire	Corrugated SS shell with braid (optional)
Movement	Axial ±25mm, Lateral ±15mm, Angular ±10°	Similar or more depending on design

3. Working

Expansion Bellows work by absorbing mechanical displacement caused by thermal expansion, vibrations, or misalignment in pipelines. When fluid or gas passes through the pipeline, changes in temperature and pressure cause expansion and contraction. The bellows compress or extend to neutralize these forces, protecting the pipeline and connected equipment.

4. Principle

The basic principle is elastic deformation. The bellows expand, compress, and flex due to the mechanical design of the convolutions (or rubber layers), allowing them to accommodate axial, lateral, and angular movements.

5. Assembly

Choose the correct bellow size and pressure rating.
Place the bellow between two pipeline flanges or joints.
Use gaskets, washers, and bolts as per standards.
Tighten bolts gradually in cross pattern to avoid leakage.
Ensure bellow is not over-compressed or stretched during installation.

6. Installation Process

Clean pipeline ends.
Align flanges accurately.
Center the bellows without axial preload.
Secure with bolts and nuts using a torque wrench.
Inspect for correct movement clearance.
Test system for leakage and expansion capability.

Note: Do not use bellows as anchors or to correct misalignments beyond allowed tolerances.

7. Technical Specification

Parameter	Value
Working Pressure	Up to 25 Bar
Burst Pressure	Up to 60 Bar
Working Temperature	-40°C to +180°C
Movement Capability	Axial: ±25 mm, Lateral: ±15 mm
Flange Standard	ANSI B16.5, DIN, BS, JIS
Leakage Test Standard	BS 5154 / API 598
Vibration Damping	Up to 90%
Lifespan	5-10 Years (Application Dependent)

8. Troubleshooting

Issue	Cause	Solution
Leakage	Improper bolt tightening, gasket misalignment	Retighten bolts, replace gasket
Cracks or bulging	Overpressure or chemical incompatibility	Replace with suitable pressure/material
No movement observed	Over-compression during installation	Ensure free axial play and correct mounting
Noise / vibration not reduced	Incorrect selection	Use proper size and damping design

9. HS Code

HS Code for Rubber Bellows: 4016.99.90
HS Code for Metallic Bellows: 8307.10.00

Double-check based on specific end-use and importing country regulations.

10. FAQs

Q1. Can Locus customize expansion bellows?
✅ Yes, we manufacture as per client drawing, size, pressure, and material needs.

Q2. Are these bellows suitable for chemical plants?
✅ Yes, we offer chemically resistant rubber and stainless steel versions for aggressive environments.

Q3. How long do Locus bellows last?
✅ Typically 5–10 years, depending on working conditions and maintenance.

Q4. Do you supply with test certificates?
✅ Yes, we provide material test reports, hydro test certificates, and third-party inspection if required.

11. Applications