Large Diameter O-Rings
Large Diameter O-Rings for Custom Equipment Requirements
Large diameter O-rings may be required when equipment uses oversized sealing grooves, large mating surfaces or non-standard interfaces.
Compared with smaller standard O-rings, large diameter O-rings can involve additional design and handling considerations, including:
- Overall ring diameter
- Cross-section size
- Groove dimensions
- Installation stretch or compression
- Material flexibility
- Assembly and handling requirements
- Storage and transportation conditions
These factors should be reviewed together. A ring that matches the nominal diameter may still be unsuitable if its cross-section, material or groove arrangement does not match the sealing design.
Large Diameter O-Rings Reference Chart
Standard: AS568 (Large Size Series) + ISO 3601, ID > 250mm, Cross Section: 3.53mm / 5.33mm / 6.99mm
| O-Ring Code | Inner Diameter (ID) | Cross Section (CS) | Outer Diameter (OD) |
|---|---|---|---|
| AS568-425 | 254.00 mm | 3.53 mm | 261.06 mm |
| AS568-426 | 266.70 mm | 3.53 mm | 273.76 mm |
| AS568-427 | 279.40 mm | 3.53 mm | 286.46 mm |
| AS568-428 | 292.10 mm | 3.53 mm | 299.16 mm |
| AS568-429 | 304.80 mm | 3.53 mm | 311.86 mm |
| AS568-430 | 317.50 mm | 3.53 mm | 324.56 mm |
| AS568-431 | 330.20 mm | 3.53 mm | 337.26 mm |
| AS568-432 | 342.90 mm | 3.53 mm | 349.96 mm |
| AS568-433 | 355.60 mm | 3.53 mm | 362.66 mm |
| AS568-434 | 368.30 mm | 3.53 mm | 375.36 mm |
| AS568-435 | 381.00 mm | 3.53 mm | 388.06 mm |
| AS568-436 | 393.70 mm | 3.53 mm | 400.76 mm |
| AS568-437 | 406.40 mm | 3.53 mm | 413.46 mm |
| AS568-438 | 419.10 mm | 3.53 mm | 426.16 mm |
| AS568-439 | 431.80 mm | 3.53 mm | 438.86 mm |
| AS568-440 | 444.50 mm | 3.53 mm | 451.56 mm |
| AS568-441 | 457.20 mm | 3.53 mm | 464.26 mm |
| AS568-442 | 469.90 mm | 3.53 mm | 476.96 mm |
| AS568-443 | 482.60 mm | 3.53 mm | 489.66 mm |
| AS568-444 | 495.30 mm | 3.53 mm | 502.36 mm |
| AS568-445 | 508.00 mm | 3.53 mm | 515.06 mm |
| O-Ring Code | Inner Diameter (ID) | Cross Section (CS) | Outer Diameter (OD) |
|---|---|---|---|
| AS568-450 | 254.00 mm | 5.33 mm | 264.66 mm |
| AS568-451 | 266.70 mm | 5.33 mm | 277.36 mm |
| AS568-452 | 279.40 mm | 5.33 mm | 290.06 mm |
| AS568-453 | 292.10 mm | 5.33 mm | 302.76 mm |
| AS568-454 | 304.80 mm | 5.33 mm | 315.46 mm |
| AS568-455 | 317.50 mm | 5.33 mm | 328.16 mm |
| AS568-456 | 330.20 mm | 5.33 mm | 340.86 mm |
| AS568-457 | 342.90 mm | 5.33 mm | 353.56 mm |
| AS568-458 | 355.60 mm | 5.33 mm | 366.26 mm |
| AS568-459 | 368.30 mm | 5.33 mm | 378.96 mm |
| AS568-460 | 381.00 mm | 5.33 mm | 391.66 mm |
| AS568-461 | 393.70 mm | 5.33 mm | 404.36 mm |
| AS568-462 | 406.40 mm | 5.33 mm | 417.06 mm |
| AS568-463 | 419.10 mm | 5.33 mm | 429.76 mm |
| AS568-464 | 431.80 mm | 5.33 mm | 442.46 mm |
| AS568-465 | 444.50 mm | 5.33 mm | 455.16 mm |
| AS568-466 | 457.20 mm | 5.33 mm | 467.86 mm |
| AS568-467 | 469.90 mm | 5.33 mm | 480.56 mm |
| AS568-468 | 482.60 mm | 5.33 mm | 493.26 mm |
| AS568-469 | 495.30 mm | 5.33 mm | 505.96 mm |
| AS568-470 | 508.00 mm | 5.33 mm | 518.66 mm |
| O-Ring Code | Inner Diameter (ID) | Cross Section (CS) | Outer Diameter (OD) |
|---|---|---|---|
| AS568-475 | 254.00 mm | 6.99 mm | 267.98 mm |
| AS568-476 | 266.70 mm | 6.99 mm | 280.68 mm |
| AS568-477 | 279.40 mm | 6.99 mm | 293.38 mm |
| AS568-478 | 292.10 mm | 6.99 mm | 306.08 mm |
| AS568-479 | 304.80 mm | 6.99 mm | 318.78 mm |
| AS568-480 | 317.50 mm | 6.99 mm | 331.48 mm |
| AS568-481 | 330.20 mm | 6.99 mm | 344.18 mm |
| AS568-482 | 342.90 mm | 6.99 mm | 356.88 mm |
| AS568-483 | 355.60 mm | 6.99 mm | 369.58 mm |
| AS568-484 | 368.30 mm | 6.99 mm | 382.28 mm |
| AS568-485 | 381.00 mm | 6.99 mm | 394.98 mm |
| AS568-486 | 393.70 mm | 6.99 mm | 407.68 mm |
| AS568-487 | 406.40 mm | 6.99 mm | 420.38 mm |
| AS568-488 | 419.10 mm | 6.99 mm | 433.08 mm |
| AS568-489 | 431.80 mm | 6.99 mm | 445.78 mm |
| AS568-490 | 444.50 mm | 6.99 mm | 458.48 mm |
| AS568-491 | 457.20 mm | 6.99 mm | 471.18 mm |
| AS568-492 | 469.90 mm | 6.99 mm | 483.88 mm |
| AS568-493 | 482.60 mm | 6.99 mm | 496.58 mm |
| AS568-494 | 495.30 mm | 6.99 mm | 509.28 mm |
| AS568-495 | 508.00 mm | 6.99 mm | 521.98 mm |
Technical Notes
- Custom large diameter o-rings up to several meters available, vulcanized joint or seamless type.
- Common materials: NBR, FKM, EPDM, Silicone, PTFE Encapsulated.
- Tolerance follows AS568 and ISO 3601 standard.
Product Features and Design Considerations
Custom Dimensions
Large diameter O-rings may be specified according to customer drawings, dimensions or equipment requirements.
The critical dimensions generally include:
| Dimension | Description |
|---|---|
| Inside Diameter (ID) | The internal diameter of the O-ring |
| Cross-Section (CS) | The thickness of the ring section |
| Outside Diameter (OD) | The overall outside diameter |
| Groove Dimensions | The mating groove dimensions used for installation |
| Tolerances | Dimensional limits required by the design |
For an O-ring with a circular cross-section, the relationship between inside diameter, cross-section and outside diameter can be expressed as:
OD = ID + 2 × CS
This relationship can be useful for preliminary dimensional checks. The final component specification should follow the drawing and the applicable dimensional tolerances.
Material Selection
The material should be selected according to the operating medium, temperature, pressure, mechanical conditions and intended service.
| Material | Common Selection Considerations | Important Checks |
|---|---|---|
| NBR Rubber | Certain oil- and lubricant-related applications | Exact fluid, temperature and compound compatibility |
| EPDM Rubber | Weathering, ozone and suitable water-related applications | Chemical exposure and temperature |
| Silicone Rubber | Flexibility and selected temperature-related requirements | Grade, mechanical loading and media compatibility |
| FKM Rubber | Certain demanding heat, oil and chemical environments | Exact medium, temperature and formulation |
| FFKM Material | Specialized chemical and high-temperature applications | Compound-specific compatibility and operating conditions |
Large Diameter O-Ring Applications
Large diameter O-rings can be considered for sealing arrangements in a range of industrial equipment, depending on the equipment design.
Industrial Equipment
Industrial machinery may use large O-rings at housing interfaces, covers, access points or other sealing locations. The ring dimensions and material should match the installation and operating conditions.
Fluid Handling Equipment
Certain fluid handling assemblies may require large diameter O-rings to seal mating interfaces. The fluid, temperature, pressure and sealing arrangement should be defined before material selection.
Equipment Maintenance and Replacement
Replacement O-rings may be required when the original component is worn, damaged or no longer available.
For replacement enquiries, provide the original part number, drawing, equipment model, dimensions and operating conditions. If the original material is unknown, application information can help guide the specification review.
Custom Large O-Ring Manufacturing Requirements
For a custom large diameter O-ring, Hengjing recommends preparing the following information:
| Required Information | Details |
|---|---|
| Part Drawing | Overall geometry and critical dimensions |
| Inside Diameter | Required internal diameter |
| Cross-Section | Ring section thickness |
| Material | Material designation or required properties |
| Operating Medium | Fluid or other contact medium |
| Temperature | Operating and relevant temperature conditions |
| Pressure | System pressure, if applicable |
| Quantity | Prototype, replacement or production quantity |
| Inspection | Dimensional or other acceptance requirements |
If a drawing is unavailable, provide measurements, photos, equipment information and the original part number. Additional dimensions may be needed before the specification can be confirmed.
Large Diameter O-Rings vs. Other Rubber Sealing Products
Different sealing products serve different interface designs. Selecting the right geometry is an important first step.
| Product | Typical Geometry | Main Application Consideration |
|---|---|---|
| Large Diameter O-Ring | Continuous ring with circular cross-section | Sealing in a compatible O-ring groove |
| Rubber Gasket | Flat or custom-shaped profile | Sealing between mating surfaces |
| Rubber Washer | Flat ring or disc | Fastener-related sealing or cushioning |
| Rubber X-Ring | Four-lobed cross-section | Sealing arrangements designed for X-ring geometry |
Hengjing also provides Rubber Gaskets and Rubber Washers for different industrial sealing requirements.
Technical Drawings and Reference Specifications
A technical drawing should define the geometry and dimensions needed to manufacture the O-ring.
Recommended drawing information includes:
- Inside diameter
- Cross-section
- Material specification
- Dimensional tolerances
- Relevant groove or installation dimensions
- Inspection requirements
A reference size chart should only be published after Hengjing confirms the actual available size range and manufacturing capability. Standard O-ring dimensions may be used where the selected specification applies, but a custom large diameter O-ring should not be presented as a standard size without verification.
Quality and Inspection Considerations
O-ring inspection requirements may include dimensional checks, visual inspection and material-related verification where specified.
Applicable standards and test methods should be selected according to the material, product type and customer requirements. For example, ISO 3601 is a relevant standard family for O-rings, but compliance should only be stated when the product has been evaluated against the applicable requirements.
For custom O-rings, the customer should identify any required inspection records, material documentation or acceptance criteria during the quotation stage.
Why Choose Hengjing for Large Diameter O-Rings?
Hengjing supports industrial rubber sealing enquiries with attention to product dimensions, material requirements and application conditions.
Our product scope includes:
For large diameter O-ring projects, we recommend providing the drawing and operating conditions so the component can be reviewed against the intended application.
Request a Quote for Large Diameter O-Rings
To request a quotation, submit your O-ring drawing, dimensions, material requirements, operating medium and quantity.
Hengjing can review the available information and clarify the details required for your custom O-ring enquiry.
Frequently Asked Questions
What is a large diameter O-ring?
A large diameter O-ring is a ring-shaped sealing component with a circular cross-section designed for larger sealing interfaces. Its dimensions and material depend on the application.
Can large diameter O-rings be made to custom dimensions?
Custom enquiries can be reviewed based on drawings, dimensions, material requirements and application conditions. Specific manufacturing feasibility should be confirmed for the requested size and specification.
How do I select a material for a large O-ring?
Consider the operating medium, temperature, pressure, mechanical conditions and required service environment. The final material should be verified for compound-specific compatibility.
What information should I provide for a large O-ring quotation?
Provide the inside diameter, cross-section, material, operating medium, temperature, pressure if applicable, drawing and quantity.
Are large diameter O-rings suitable for pipeline applications?
They may be considered for suitable sealing interfaces, depending on the pipeline design and connection arrangement. The exact application, dimensions, material and operating conditions must be reviewed.
Can Hengjing provide replacement large O-rings?
Replacement enquiries can be reviewed using the original part number, drawing, equipment model, dimensions and operating conditions.