Transcript MANE 6960 Project Presentation.pptx

Wear of Elastomer Seals
Analysis of Seal Profile
Devin Murray
MANE 6960 Friction, Wear & Lubrication
Project Goal
• Evaluate different elastomer seal profiles to
determine characteristics which increase
resistance to abrasive wear.
Seal Profiles
O-Ring
Quad Ring
Quad-O-Dyn Seal
Analysis Results
Standard O-Ring
The standard o-ring profile has the lowest overall peak contact
stress in large part due to the contact area of the deformed seal and
the cylinder being the greatest of the three seals evaluated. This
results in a seal which is the weakest initially in overall sealing
strength (i.e. the standard o-ring is the least capable of the three
seals in withstanding differential pressure without leakage). The
large contact area of the seal with the cylinder also presents the
worst prospect with regard to abrasive wear during dynamic travel.
As the standard o-ring wears and material is removed, a significant
decrease in seal compression can be expected which ultimately
leads to failure of the o-ring to contain differential pressure and
leakage rates will reach unacceptable levels.
Analysis Results
Quad Ring Seal
The Quad Ring seal has the highest overall peak
contact stress which is due to this seal profile having
the smallest contact area with the cylinder of all
profiles evaluated. The high contact stress results in
a very strong seal strength; however this will also
result in increased wear of the sealing ‘lobes’ when
compared with the Quad-O-Dyn seal. With all facts
considered, the Quad Ring should perform better
than the standard o-ring due to the small contact
area of the seal exposed to abrasive wear and the
geometry of the seal being such that wear at the
two ‘lobes’ should not greatly decrease the seal
compression. This is because the majority of the
compressed seal material resides in the ‘main body’
of the seal and is unaffected by wear. Conversely,
the Quad Ring is likely to fail sooner due to wear
than the Quad-O-Dyn seal due to the comparatively
higher contact stress.
Analysis Results
Quad-O-Dyn Seal
The peak contact stress of the Quad-O-Dyn seal profile
falls roughly in the middle of the standard o-ring and Quad
Ring stresses. As the general seal geometry of the QuadO-Dyn seal profile is very similar to the Quad Ring, it is
apparent that the same positive aspects of the engineered
profile are maintained (strong seal strength, low contact
area exposed to abrasive wear, and maintaining seal
compression despite wear at seal ‘lobes’). Therefore, due
to the decreased contact stress when compared to the
Quad Ring, the Quad-O-Dyn seal is expected to wear at a
decreased rate resulting in a greater seal life prior to
failure.
Conclusion
• Quad-O-Dyn seal offers the best sealing
strength with the most resistance to abrasive
wear during seal travel.
• Further study should be pursued regarding
seals with additional ‘lobes’ to find the
optimal engineered seal profile.