Buy O-Rings and O-Ring Kits Online in Australia
O-Rings & O-Ring Kits — NBR, Viton, Metric, Imperial & BS Series
O-rings are the workshop default for static and dynamic sealing in hydraulic cylinders, pump shafts, pneumatic fittings, equipment housings and any rotating or reciprocating shaft. A single failed o-ring takes a machine down — or worse, contaminates a fluid system or creates a safety hazard. AIMS Industrial stocks 25 o-ring lines including NBR 70 (nitrile) and Viton 75 (FKM fluoroelastomer) compounds across metric, imperial and British Standard (BS) series, plus oil seal and o-ring cord by the metre. Manufactured to AS 1646.10 / ISO 3601 dimensional standards.
O-Ring Material Quick Reference
| Compound | Temperature | Best For | Avoid |
| NBR 70 (Nitrile) | -40 to +120°C | Mineral oil, hydraulic fluid, fuel, water, air | Ketones, esters, brake fluid, ozone |
| Viton 75 (FKM) | -20 to +200°C | Fuel, solvents, hot oils, aggressive chemicals | Ketones, esters, amines, hot water/steam |
| EPDM | -40 to +150°C | Hot water, steam, brake fluid, ozone | Petroleum oils, fuel |
| Silicone | -60 to +230°C | Static seals at extreme temperatures, food-grade | Dynamic sealing, fuel, solvents |
For full chemical compatibility — including the 82-chemical resistance chart across NBR, Viton, EPDM and Silicone — see the O-Ring Selection Guide covering sizing, materials and the chemical resistance chart.
The AIMS O-Ring & Oil Seal Range
Our seal range covers the most common industrial sealing requirements across hydraulic, pneumatic, fluid handling and rotating machinery applications:
- NBR 70 O-rings (metric): NBR (nitrile butadiene rubber) 70 Shore A hardness in metric cross-sections 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 4mm and 5mm with comprehensive ID coverage. The standard o-ring compound for mineral oils, hydraulic fluids, fuels, water and air service across -40°C to +120°C.
- NBR 70 O-rings (imperial): imperial NBR o-rings for non-metric equipment and AS/BS pipe fitting applications. Metric and imperial sizes can look very similar — always confirm cross-section and ID in millimetres before ordering.
- NBR O-rings (BS series): British Standard (BS 1806) o-rings in the BS1–BS932 numbering system for equipment specified to BS dimensions. Common in older UK and Australian industrial machinery, compressors and hydraulic systems.
- Viton 75 O-rings (metric & imperial): Viton (FKM) 75 Shore A o-rings provide superior chemical resistance to fuels, solvents and hydraulic fluids, and high-temperature service to +200°C. Required where NBR would swell, crack or harden in service.
- Oil seals: metric and Viton lip-type oil seals for rotating shaft sealing in gearboxes, pumps, motors and axles. Critical for preventing oil egress and contaminant ingress in rotating machinery. Viton suits high-temperature and chemical-exposure applications where standard NBR seals fail prematurely.
- O-ring cord: NBR o-ring cord by the metre for custom-size o-rings made on-site by cutting to length and joining with o-ring splicing compound. Used for large-bore or non-standard sizes not available as moulded rings.
Static vs Dynamic Seal Selection
Two principal sealing modes drive groove design and material choice:
- Static seals — between two non-moving surfaces (e.g., flange face, threaded plug, end cap). Less critical surface finish (Ra 1.6 typical) and groove dimensioning, but compound choice still matters for media and temperature compatibility.
- Dynamic seals — on moving surfaces (rotating shaft, reciprocating piston rod, sliding fitting). Need precise surface finish (Ra 0.4-0.8 on the sealing face), correct groove dimensions per ISO 3601-2, and the right material to balance hardness with extrusion resistance. Wrong compound on a dynamic seal causes premature failure within hours.
O-Ring Sizing — Measure Twice, Order Once
O-rings are specified by inside diameter (ID) × cross-section (CS) diameter. Both dimensions must be measured on the original seal — relying on housing dimensions alone introduces incorrect compression values and leads to premature failure. Use a caliper for cross-section and a vernier or pin gauge for ID. If the existing seal is damaged, measure the housing groove and add typical groove allowances per ISO 3601-2 — or send dimensions to our team for sizing.
Companion Sealing Ranges at AIMS
- Oil Seals & O-Rings — the broader sealing range covering rotary lip seals, V-rings and shaft seals (96 lines).
- Gaskets — PTFE, graphite, fibre and rubber sheet gaskets, plus spiral wound gaskets for flange applications. See the Spiral Wound Gasket Guide for ASME B16.20 colour codes and flange standards.
- Hose Clamps — for flexible-line connections that pair with o-ring fittings.
- Loctite — anaerobic flange sealants, RTV silicone gasket makers and pipe thread sealants. See the RTV Silicone Gasket Maker Guide and the broader Industrial Adhesive Types Guide.
- Pipe Flanges — matching gasket size to flange type.
- Hydraulics and Pneumatics — cylinders, valves and fittings that use o-ring sealing.
Standards & Quality
AIMS o-rings are manufactured to AS 1646.10 (Australian Standard for elastomeric o-rings) and ISO 3601 (international o-ring dimensions, tolerances and groove design). Compound grades are batch-tested for hardness (Shore A), tensile strength and elongation to ensure consistent performance batch-to-batch. The BS series follows BS 1806 dimensional conventions for legacy British-Standard equipment.
Order O-Rings from AIMS Industrial
As a proudly Australian business since 1988, we stock locally and work with trusted Australian manufacturers and distributors to ensure fast, reliable supply. Can't identify your seal size or compound? Call (02) 9773 0122, contact our team or request a quote — send us the dimensions and we'll identify the correct seal.