Dimensions and tolerances

Dimensions in the measurement table:
D - internal diameter size [mm]: internal diameter D tolerance
d – cross-section diameter size [mm]: cross-section diameter d tolerance

Find the desired size - FPM O-ring and others
Find the desired size - NBR O-ring and others

Elements of standardisation - norms.

• PN - 64/M - 73093 - sealing rings with circular cross-section for resting connections - dimensions.
• PN - 60/M - 86961 - sealing rings with circular cross-section - dimensions.
• PN - 90/M - 73060 - sealing rings with circular cross-section - sizes in accordance with ISO - dimensions and dimension markings.
• PN - 90/M - 73092 - sealing rings with circular cross-section - requirements and tests.
• ISO 3601/3 Fluid system.
• DIN 3771 O-ringe Fluidtechnik.

Division and markings

Material

Sealing O-rings are made from rubber with properties given in table 1 and with exemplary standard properties given in tables 1.1., 1.2., 1.3. in accordance with PN - 90/M - 73092.

Symbols used in mix requirements sheets:

• d – ring cross-section diameter
• D – internal ring diameter
• Ect - permanent deformation under compression
• Er - relative elongation after breaking
• f – electric current frequency
• G, m - mass
• H - hardness
• KsGr – grindability on Grassel's apparatus
• KsSch - grindability on Schoper's apparatus
• Kw - frost resistance coefficient
• Rr – break strength
• Rrd – rip strength
• Rs – electric surface resistance
• t - time
• Tk – low temperature resistance
• V - volume

Marking structure

A marking contains at least:

• the name /symbol/ "O"
• dimensions D x d
• the literal symbol of natural rubber according to tables 1 and 2
• hardness according to table 1
• the symbol of the manufacture class - option: N-normal application, S-special application
• requirement norm number.

An example of a marking

Sealing ring D=30 mm, d=2 mm, material: FPM with Shore’s hardness at 80.

RO 30.00 x 2.00 FPM80

Requirements

• Properties of rubber according to Eriks based on samples and rings according to table 4.
• Standard properties of rubber according to PN - 90/M - 73092 on normalised samples according to table 1 and 1.1., 1.2., 1.3.
• Standard properties of rubber on rings according to table 3.

The data present in this study are for information only. They may not be used as a basis for civil legal claims. Detailed questions should be directed to the Manufacturer. The Manufacturer reserves the right to introduce changes, according to new technical solutions and progress in the area of technologies and materials.