Buy Rubber Bellows Online in Australia
What is a rubber bellows?
A rubber bellows is a flexible flanged pipe section used in industrial pipework to absorb vibration, thermal movement and minor misalignment between adjacent rigid pipe runs. It connects two flanges and flexes axially, laterally and angularly within published limits, isolating equipment vibration from the rest of the pipework. AIMS Industrial supplies AAP rubber pipe bellows in EPDM and NBR compounds, sized DN50 to DN250 with Table-E, ANSI 150 or BS 4504 PN16 flange faces.
What are rubber bellows used for?
Rubber bellows are installed on pump suction and discharge lines, HVAC chilled water and condenser circuits, cooling tower piping, chemical process lines and diesel and fuel transfer skids. They protect pipework from pump vibration, accommodate thermal expansion and reduce noise transmission.
What is the difference between EPDM and NBR bellows?
EPDM rubber is used for water, steam, cooling circuits and most aqueous chemical service. It resists heat, weathering and ozone, but is not suitable for oil or fuel — those will swell and degrade EPDM. NBR (nitrile) rubber is used for oil, fuel, hydraulic oil and other petroleum-based media, but has poorer outdoor weathering than EPDM.
Rubber Pipe Bellows & Flexible Joints — Quick Reference
AAP rubber pipe bellows are used in industrial pipeline systems to absorb vibration, thermal movement, and minor misalignment between flanged pipe sections. Available in EPDM and NBR rubber compounds; sized DN 50 to DN 250 (2" to 10"); supplied with Table-E, ANSI 150 or BS 4504 PN16 flange faces to match common Australian and international piping standards.
| Spec | Range / Standard |
|---|---|
| Materials | EPDM (water, steam, chemicals) · NBR (oil, fuel, hydrocarbons) |
| Sizes | DN 50, 65, 80, 100, 125, 150, 200, 250 mm (2"–10") |
| Flange standards | Table-E (AS 4087), ANSI B16.5 Class 150, BS 4504 PN16 |
| Working pressure | Up to 16 bar (Class 150 equivalent) — verify per specific model |
| Working temperature | EPDM: –40 °C to +120 °C · NBR: –20 °C to +100 °C |
| Movement absorbed | Axial, lateral and angular — refer manufacturer's published values |
Materials — EPDM vs NBR
EPDM (Ethylene Propylene Diene Monomer) rubber is the right choice for water service, cooling circuits, steam, and most aqueous chemical applications. EPDM resists heat, weathering, ozone and dilute acids well. It is NOT suited to mineral oil, fuel or hydrocarbon service — those will swell and degrade EPDM rubber.
NBR (Nitrile / Buna-N) rubber is the standard for oil and fuel service — diesel, hydraulic oil, lubricating oils, LPG and other petroleum-based media. NBR has poor weathering resistance compared to EPDM, so for outdoor pipework carrying water, prefer EPDM. For chemical compatibility queries on specific media, call our team — material selection on bellows is critical because failure typically means a leak and downtime.
Flange Standards — Table-E vs ANSI 150 vs BS 4504
Table-E (AS 4087) is the Australian water industry standard for cast iron and ductile iron flanges. It is widely used in municipal water, wastewater, fire service and irrigation pipework. The dimensions differ from ANSI 150 — Table-E flanges will NOT bolt up to ANSI flanges of the same nominal size. Specify Table-E when matching existing Australian water pipework.
ANSI 150 (ASME B16.5 Class 150) is the US-derived flange standard common in process plant, chemical and oil-and-gas piping. It is the dominant standard for imported skid-mounted equipment, pumps and process modules. ANSI 150 covers up to 285 psi at ambient temperature.
BS 4504 PN16 is the European metric standard. PN16 = 16 bar nominal pressure. Common on imported European pumps, chemical equipment and process plant. PN16 dimensions differ from both Table-E and ANSI 150.
Applications
- Pump suction and discharge — absorbs pump vibration before it transmits into rigid pipework, extending pipe and fitting fatigue life
- HVAC chilled water and condenser circuits — accommodates thermal expansion across long pipe runs
- Cooling tower circuits — handles thermal cycling and equipment vibration
- Chemical process pipelines — absorbs movement at vessels, exchangers and pump skids
- Diesel and fuel transfer (NBR only) — pump skids, generator fuel lines, tank farm transfer
- Mining and quarry slurry circuits — vibration isolation for thickener and dewatering plant
Sizing & Installation
Bellow length and movement capacity are specified per manufacturer. Two common installation rules: (1) bellows must NOT be used to correct gross pipework misalignment — they are designed for movement absorption, not joint repair; and (2) anchor and guide brackets must be installed either side of the bellows to prevent pressure thrust extending the unit beyond its design movement. For high-pressure or large-bore applications, control rod assemblies may be required to limit elongation under fault conditions. For specification help, call (02) 9773 0122 or contact our team.
Companion ranges at AIMS
Rubber bellows sit within our broader pipes, tubes & fittings range. For threaded pipe connections, see pipe fittings. For sealing and gasket selection, see gaskets and our spiral wound gasket guide. For hose-based flexible connections (vs flanged bellows), see hoses and hydraulic hoses.
People Also Ask — Rubber Bellows and Expansion Joints
Q: What's a rubber bellows?
A rubber bellows (also called a rubber expansion joint or flexible coupling) is a flexible pipe section that absorbs vibration, thermal expansion, and misalignment in piping systems. Rubber elastomer with internal reinforcement and end flanges allows the bellows to flex while maintaining pressure containment. Used in industrial piping (pumps, compressors, refrigeration systems, water and wastewater lines) to isolate machinery from rigid pipe and reduce vibration transmission.
Q: When do I need a rubber bellows?
Anywhere a pipe connects to vibrating equipment (pumps, compressors, chillers, generators) — the bellows absorbs vibration and prevents pipe stress. Also: thermal expansion compensation on long pipe runs, misalignment tolerance during installation, noise reduction in HVAC systems, and absorbing surge pressure spikes. Without bellows, pipe stress from vibration causes flange leaks, support failures, and eventually pipe cracks.
Q: What rubber material for which fluid?
EPDM: water, steam, mild chemicals, hot water systems. NBR (nitrile): oils, fuels, hydraulic fluids. Neoprene: general industrial, good weather resistance. CSM (Hypalon): chemical resistance, ozone exposure. PTFE-lined: aggressive chemicals, food/pharma. Match the rubber to the fluid chemistry and temperature. Wrong rubber rapidly degrades — Hypalon in oil service swells and tears; nitrile in caustic service degrades.
Q: What size rubber bellows do I need?
Match nominal pipe size (DN50, DN100, DN150 etc.) and pressure rating (typically PN10 for general industrial, PN16 for higher pressure). Length depends on the expected movement (axial compression/extension, lateral offset, angular) and the bellows design. Manufacturer publishes movement capacity for each model. For sustained service, oversize the bellows pressure rating by 25-30% above system pressure. For very high temperature or pressure, specialty engineered bellows required.
Q: How long do rubber bellows last?
Typical service life 5-15 years depending on operating conditions, chemical exposure, and movement frequency. UV exposure outdoors reduces life dramatically — use UV-resistant compounds (EPDM, CSM) outdoors or shield from direct sunlight. Visible signs of failure: surface cracking, bulging, ply separation, leakage at end flanges. Replace before failure — sudden bellows failure releases system fluid and shuts equipment unexpectedly. Plan replacement during scheduled maintenance, not after failure.