Backup Rings - PARKER 8-DASHS
Parbak® Contoured Continuous Back-up Rings
Parbak is a supplement to a pressure seal such as an O-ring. It
is not a seal in itself.
reason for the use of a back-up ring is to reduce the clearance
gap on the low pressure side of an O-ring or similar type seal.
An O-ring and Parbak combination will withstand much higher pressures
than an O-ring alone.
Parbak back-up rings are outstanding for several reasons. To begin
with, Parbaks are molded of a hard rubber compound in one continuous
circle, yet they can be stretched easily into place. Because they
are not split or spiraled, Parbaks do not cause the localized
wear on O-rings characteristic of back-up rings of that type of
proved to last longer with greater reliability than all other
types of back-up rings tested. They are lower in cost than competitive
the operating pressure range of O-rings or other types of seals.
Some additional benefit such as increased lubrication of the O-ring
may also be obtained because the Parbak will trap small amounts
of lubricant between itself and the O-ring.
The use of
Parbaks permits a far greater metal-to-metal clearance between
moving parts. This helps overcome difficulties encountered with
wide or out-of-tolerance bores and shafts.
nature of the O'ring seal and the clearance reducing capability
of the Parbak offers an important cost reduction opportunity.
In many applications, machining tolerances can be increased at
a considerable dollar savings.
- Easy to
- Cost reduction
for better performance
- Low in
materials and sizes
- Total Diametral
Custom | Leather
| Parker 8-Dashs | Rubber
| Teflon |