Mechanical seals: How to Choose O-ring?(III)

- Jul 09, 2018-

In order to better serve you, this topic is divided into five parts, to explain to you how to better use the O-ring. To make your business more robust, and public safety can be better guaranteed.


This is the second part of the main elements:

1 Working medium and working conditions

When selecting O-ring materials, the compatibility with the working medium should be considered first. It is also necessary to consider the working conditions such as pressure, temperature, continuous working time and operating cycle of the seal. If used in a rotating environment, the temperature rise due to frictional heat must be considered. Different seal materials have different physical and chemical properties.

2 Sealed form

 According to the type of load, it can be divided into static seal and dynamic seal; according to the sealing use, it can be divided into hole seal, shaft seal and rotary shaft seal; according to its installation form, it can be divided into radial installation and axial installation. For radial mounting, the deviation between the inner diameter of the O-ring and the diameter d2 to be sealed should be as small as possible for the seal of the shaft; for the seal of the hole, the inner diameter should be equal to or slightly smaller than the diameter d1 of the groove.

Mechanical seals o ring.jpg

   When installing axially, consider the direction of pressure. For internal pressure, the outer diameter of the O-ring should be about 1-2% larger than the outer diameter d3 of the groove; for external pressure, the inner diameter of the O-ring should be about 1 to 3% smaller than the inner diameter d4 of the groove.

Contact Us:

Shaanxi DaoLin Mechanical & Electrical Co.,Ltd

Room1107, Building B, Sail Times Plaza, Hou Wei Zhai, Wei Yang 

District, 710085, Xi’an  City, Shaanxi Province, China

Tel.:+86(029)84523807-802 Fax: +86(029)84523807-808