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Hydraulic kits
Boss, Face, and Flange O-Rings
Boss O-rings, face O-rings, and flange O-rings are commonly used sealing components in hydraulic systems, providing efficient and stable sealing protection under high-pressure conditions. All three types of O-rings have specific size specifications and must be precisely matched with their corresponding fittings. Products can be purchased as a set or individually. Click on any O-ring category below to jump to the corresponding section for details.
KODA O-Rings
O-Ring Face Seals
Flange O-Rings
KODA O-Rings
KODA O-rings are specifically designed for sealing straight-threaded BOSH joints in hydraulic equipment and are suitable for medium to high-pressure hydraulic systems. KODA brand O-rings are recommended. KODAO O-rings strictly conform to the AS568 900 series standard. Standard models are made of nitrile butadiene rubber (NBR) with a hardness of 90 degrees, while custom options in various materials are also available to meet the sealing requirements of different media and environments.
KODA O-ring Size Chart
The interactive table below displays the sizes of KODAO O-rings and their corresponding specifications. The first column indicates the outer diameter of the pipe corresponding to the O-ring size. The numbers in the second column link to the corresponding size filter page in our online store.
| Tube 0D | AS568 Dash # | CS Inch | ID inch |
|---|---|---|---|
| 3/32 | 901 | 0.056 | 0.185 |
| 1/8 | 902 | 0.064 | 0.239 |
| 3/16 | 903 | 0.064 | 0.301 |
| 1/4 | 904 | 0.072 | 0.351 |
| 5/16 | 905 | 0.072 | 0.414 |
| 3/8 | 906 | 0.078 | 0.468 |
| 7/16 | 907 | 0.082 | 0.53 |
| 1/2 | 908 | 0.087 | 0.644 |
| 9/16 | 909 | 0.097 | 0.706 |
| 5/8 | 910 | 0.097 | 0.755 |
| 11/16 | 911 | 0.116 | 0.863 |
| 3/4 | 912 | 0.116 | 0.924 |
| 13/16 | 913 | 0.116 | 0.986 |
| 7/8 | 914 | 0.116 | 1.047 |
| 1 | 916 | 0.116 | 1.171 |
| 1-1/8 | 918 | 0.116 | 1.355 |
| 1-1/4 | 920 | 0.118 | 1.475 |
| 1-1/2 | 924 | 0.118 | 1.72 |
| 1-3/4 | 928 | 0.118 | 2.09 |
| 2 | 932 | 0.118 | 2.337 |
O-ring end face seal
O-ring face seals are also suitable for sealing hydraulic systems. These O-rings are pre-installed inside the joint face, forming a reliable sealing barrier between the two mating metal surfaces. When the joint is tightened, the O-ring is compressed and tightly conforms to the plane of the joint or pipeline, thus achieving a seal. Their dimensions strictly adhere to the AS568 zero-series standard; in terms of material, 90-degree hardness nitrile rubber (NBR) O-rings are the most common, but various other materials are also available to meet different operating conditions.
O-ring end face seal dimension table
The table below lists the dimensions of O-ring face seals and their corresponding specifications. The first column corresponds to the ORS pipe diameter, and the numbers with short dashes in the second column link to the corresponding size filter page in our online store.
| ORS Tube Size | Nominal Tube 0D | AS568 Dash # | CS Nominal | ID Nominal | OD Nominal | GS Inch | ID inch |
|---|---|---|---|---|---|---|---|
| -4 | 1/4 | 011 | 1/16 | 5/16 | 7/16 | 0.07 | 0.301 |
| -6 | 3/8 | 012 | 1/16 | 3/8 | 1/2 | 0.07 | 0.364 |
| -8 | 1/2 | 014 | 1/16 | 1/2 | 5/8 | 0.07 | 0.489 |
| -10 | 5/8 | 016 | 1/16 | 5/8 | 3/4 | 0.07 | 0.614 |
| -12 | 3/4 | 018 | 1/16 | 3/8 | 7/8 | 0.07 | 0.739 |
| -16 | 1 | 021 | 1/16 | 15/16 | 1-1/16 | 0.07 | 0.926 |
| -20 | 1-1/4 | 025 | 1/16 | 1-3/16 | 1-5/16 | 0.07 | 1.176 |
| -24 | 1-1/2 | 029 | 1/16 | 1-1/2 | 1-5/8 | 0.07 | 1.489 |
Flange O-Rings
Bolted flange O-rings are suitable for sealing applications in high-pressure fluid systems such as pipelines, pumps, and valves. The flange connection assembly consists of two flat metal end faces. During assembly, the O-ring is inserted between the end faces as a sealing gasket, and the O-ring is tightened with bolts to form a stable sealing structure. This flange connection is detachable, facilitating future system modifications, cleaning, and maintenance. The dimensions of these O-rings strictly adhere to the AS568 200 series standard. The standard material is 90-degree hardness nitrile rubber (NBR), but various specialty materials are also available to meet the sealing requirements of different media and operating conditions.
If you require more information about KODA O-rings, O-ring face seals, or flange O-rings, please call +86 18730921709 or fill out the product inquiry form to get a quote or more information.
Flange O-ring Size Table
The interactive table below displays the dimensions and corresponding specifications of flange O-rings. 90-degree hardness nitrile rubber flange O-rings are available in two pressure ratings: No. 61 (maximum pressure resistance 3000 PSI, suitable for standard pressure conditions) and No. 62 (maximum pressure resistance 6000 PSI, suitable for high-pressure conditions). The first column of the table lists the flange dimensions in inches; the numbers with short horizontal lines in the second column are links that will take you to the corresponding size’s filter page on the product page.
| SAE Flange Size | AS568 Dash # | Tubing Dash Size | CS Nominal | ID Nominal | OD Nominal | GS Inch | ID inch |
|---|