An O ring is usually known as toric joint or
packing. It is a mechanical gasket with the shape of torus. It looks like
elastomer with round cross-section, which is specially designed to be seated in
the groove and compressed during the assembly that is exactly between 2 or more
parts. It is usually to create a seal at the joints.
Where O
rings used?
In static and dynamic applications
Static – used where there is a relative motion between
their parts and the O ring
Dynamic – used in
hydraulic cylinder pistons and rotating pump shafts
Sizes
O-rings come in different sizes such as
British standard, which are metric or imperial sizes. The dimensions of o-ring
are thickness, outer dimension, and inner dimension. British standard rings
defined by a standard reference, while the metric o-rings defined by thickness
x internal dimension. Typical formula is internal dimension x cross section.
How to
select O-ring?
- It’s based on the lubrication requirements, application temperature, size, chemical compatibility, durometer, sealing pressure and cost
- Based on the nature of the application, we can select the type of O-rings because it sustains the pressure adequately
- Different choices such as Silicone, EPDM, Flurosilicone, etc. Select the best choice based on the application like which O-rings handle the seal, temperatures, etc
- Just figure out squeeze ratio because how force applied against hardware that results in tightening the seal
- Consider the design of the hardware, so that you can select right type of O-ring which tolerates the pressure and compression
- Choose most sustainable O-ring type for particular application, consider physical factors of pressure and temperature levels
How to
achieve optimum performance?
Metals – It moves over O-rings that have the hard surface such as chrome
plated, steel, etc. While selecting soft metals like bronze, brass or
aluminium, special attention required
Squeeze – Minimum diametric must observed for a good sealing. When friction
is critical, pressure is low the amount of squeeze decreased but caution should
excercized
Surface Finish – Surface finish should be held at a maximum
finish of 16 RMS, although if you see groove finish have a maximum of 32 RMS
Cleanliness – Clean the systems that make free from the chips, grit, dirt and
especially foreign items. Types of abrasive material will cut the O-ring. If
you replace O-rings, kindly have a metal chip embedded into O-ring that means a
pump issue
Wye-valley -
a leading manufacturer of rubber mouldings, rubber components and post moulding
operations in the UK over twenty years. We manufacturerubber O-rings and supplies for
various industries such as marine, electronic, automotive, medicals, etc.
 |
| O Rings Manufacture |
