164
BEARING
I S O L ATO R S
Bearing isolators
General information on bearing
isolators
'Bearing isolators' is the common designation for various types of non-contact seals
for bearing housings. This group includes
seals based on labyrinth technology. This
technology entails that service life is nearly
unlimited since the sealing surfaces do not
come in contact with one another. Bearing
isolators do not wear on the shaft as no
dynamic components touch them.
Hence there are no demands in terms of
shaft hardness either. Bearing isolators
Garlock
Guardian™
– metallic
bearing isolators
generally have a significantly longer service
life than traditional radial seals. Bearing
isolators are not designed for use in applications entirely surrounded by liquid. Unlike
radial seals, bearing isolators do not require
lubrication. This makes them very well
suited to dry running. Garlock GuardianTM
and Iso-Gard® bearing isolators are tested
as per the standard IEEE-841/ NEMA MG1,
which means that advanced labyrinth technology is used to seal against both airborne
Material description
Unique design with an internal component
which holds the parts together and at the
same time prevents metal-on-metal contact.
No wear on shaft or metal components.
Simple installation with no need for press
tools. Rated to IP 56 as per NEMA MG
1-2003. API-approved. Designed according
to the bearing housing of the equipment.
Design parameters
Temperature:
-35°C to +204°C
Shaft run-out:
up to 0.50 mm
Axial movement:
up to 0.65 mm
Surface speed:
Standard material:
up to 60 m/s
bronze with FKM O-rings
particles and liquids – IP 55 and IP 56. IP
class 55 – Dustproof at a vacuum of 0.95
ata and a flow of 100 ml/s. Watertight at a
flow of 12 l/min. IP class 56 – Dustproof at a
vacuum of 0.95 ata and a flow of 100 ml/s.
Watertight at a flow of 100 l/min.
A questionnaire can be found in the
“Questionnaire” section on page 234 and
on our website at www.specmaseals.com/
Products
SPECMA SEALS HANDBOOK
B E A R I N G I S O L AT O R S
165
Garlock GuardianTM installation dimensions, mm:
Garlock
Iso-Gard®
Type
B
FB
H
29602
17.8
8.3
29607
15.9
29619
FH
min Ød
max ØD
9.5-50.8
22.2
292.1
9.5
4.8-12.7
22.2
139.7
15.9
-
9.5-50.8
22.2
292.1
29609
9.5
-
8.3-50.8
22.2
139.7
29616
25.4
9.5
4.8-15.9
4.4
22.2
292.1
29616
25.4
9.5
16.0-50.8
1.6
22.2
292.1
29620
17.8
8.3
9.5-15.9
4.4
22.2
292.1
29620
17.8
8.3
16.0-50.8
1.6
22.2
292.1
29621
15.9
9.5
4.8-9.5
3.6
22.2
139.7
29621
15.9
9.5
9.6-12.7
1.6
22.2
139.7
29697
22.2
9.5
9.5-50.8
22.2
292.1
Installation dimensions, mm:
– non-metallic
bearing isolators
Installation dimensions for types 29502, 29507
and 29516.
Material description
Specially designed for corrosive environments.
No wear on shaft. Simple installation with
no need for press tools. Rated to IP 55 as
per NEMA MG 1-2003. Designed according
to machine dimensions.
Design parameters
Temperature:
-34°C to +204°C
Shaft run-out:
up to 0.50 mm
Axial movement:
up to 0.38 mm
Surface speed:
Standard material:
up to 23 m/s
FDA approved, glass-filled
PTFE with FKM O-rings
Installation dimensions for types 29518, 29519, 29520 and 29521.
Type
A
B
x
y
29502
19
9.5
9.5-36.5
3.2
29507
15.9
6.4
4.8-12.7
4.8
29519
16.26
-
9.5-25.4
-
29516
25.4
15.0
min. 4.8
3.2
29518
22.2
9.5
15.9-25.4
3.2
29520
19.3
9.8
9.5-25.4
12.57
29521
22.48
9.8
9.5-25.4
12.57
166
SPECMA SEALS HANDBOOK
B E A R I N G I S O L AT O R S
Bearing isolators: Different variants
Temperature range
Max. surface
speed
Axial
movement
Shaft
run-out
Bronze*
Unitizing ring of filled
PTFE.
O-rings of fluoroelastomer are
standard.
-35°C to +200°C
60 m/s
±0.65 mm
±0.50 mm
Atmospheric
pressure
No internal metal-tometal contact.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Fits cross sections as
small as 4.75 mm.
Bronze*
Unitizing ring of filled
PTFE.
O-rings of fluoroelastomer are
standard.
-35°C to +200°C
60 m/s
±0.35 mm
±0.25 mm
Atmospheric
pressure
Without flange
29619
No internal metal-tometal contact.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Does not protrude
outside face of bearing
housing.
Bronze*
Unitizing ring of filled
PTFE.
O-rings of fluoroelastomer are
standard.
-35°C to +200°C
60 m/s
±0.65 mm
±0.50 mm
Atmospheric
pressure
Without flange, narrow width
29609
No internal metal-tometal contact.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Flangeless design, fits
in spaces as narrow as
9,5 mm.
Bronze*
Unitizing ring of filled
PTFE.
O-rings of fluoroelastomer are
standard.
-35°C to +200°C
60 m/s
±0.35 mm
±0.25 mm
Atmospheric
pressure
For split bearing housings
29616
No internal metal-tometal contact.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Standard and special
versions for split bearing
housings.
Bronze*
Unitizing ring of filled
PTFE.
O-rings of fluoroelastomer are
standard.
-35°C to +200°C
60 m/s
±0.65 mm
±0.50 mm
Atmospheric
pressure
GUARDIAN™
Properties
Material
Standard, flanged
29602
No internal metal-tometal contact.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Small cross section
29607
*Other materials may also be supplied. Contact us for further information.
Special types can be quoted on request.
Pressure
SPECMA SEALS HANDBOOK
B E A R I N G I S O L AT O R S
Bearing isolators: Different variants
GUARDIAN™
Properties
Material
For vertical shafts
29620
No internal metal-tometal contact.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
For upper installation in
vertical bearing housings.
For vertical shafts
29621
Temperature range
Max. surface
speed
Axial
movement
Shaft
run-out
Pressure
Bronze*
Unitizing ring of filled
PTFE.
O-rings of fluoroelastomer are
standard.
-35°C to +200°C
60 m/s
±0.65 mm
±0.50 mm
Atmospheric
pressure
No internal metal-tometal contact.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
For upper installation in
vertical bearing housings.
Bronze*
Unitizing ring of filled
PTFE.
O-rings of fluoroelastomer are
standard.
-35°C to +200°C
60 m/s
±0.35 mm
±0.25 mm
Atmospheric
pressure
For shafts with reduced diameter
29697
No internal metal-tometal contact.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Special design for individual applications.
Bronze*
Unitizing ring of filled
PTFE.
O-rings of fluoroelastomer are
standard.
-35°C to +200°C
60 m/s
±0.65 mm
±0.50 mm
Atmospheric
pressure
ISO-GARD®
Properties
Material
Temperature range
Max. surface
speed
Axial
movement
Shaft
run-out
Pressure
Standard, flanged
29502
Excellent chemical
resistance.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Blue, glass-filled
PTFE, FDA quality*.
O-rings of fluoroelastomer are
standard.
-40°C to +200°C
23 m/s
±0.38 mm
±0.50 mm
Atmospheric
pressure
Small cross section
29507
Excellent chemical
resistance.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Fits in cross sections as
small as 4.75 mm.
Blue, glass-filled
PTFE, FDA quality*.
O-rings of fluoroelastomer are
standard.
-40°C to +200°C
23 m/s
±0.38 mm
±0.25 mm
Atmospheric
pressure
*Other materials may also be supplied. Contact us for further information.
Special types can be quoted on request.
167
168
SPECMA SEALS HANDBOOK
B E A R I N G I S O L AT O R S
Temperature range
Max. surface
speed
Axial
movement
Shaft
run-out
Pressure
Blue, glass-filled
PTFE, FDA quality*.
O-rings of fluoroelastomer are
standard.
-40°C to +200°C
23 m/s
±0.38 mm
±0.25 mm
Atmospheric
pressure
Excellent chemical
resistance.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Standard and special
versions for split bearing
housings.
Blue, glass-filled
PTFE, FDA quality*.
O-rings of fluoroelastomer are
standard.
-40°C to +200°C
23 m/s
±0.38 mm
±0.25 mm
Atmospheric
pressure
Grease purgeable
29518
Excellent chemical
resistance.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Permits degreasing/
cleaning without removal.
Blue, glass-filled
PTFE, FDA quality*.
O-rings of fluoroelastomer are
standard.
-40°C to +200°C
23 m/s
±0.38 mm
±0.25 mm
Max. 0.3 bar
For vertical shafts
29520
Excellent chemical
resistance.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
For upper installation in
vertical bearing housings.
Blue, glass-filled
PTFE, FDA quality*.
O-rings of fluoroelastomer are
standard.
-40°C to +200°C
23 m/s
±0.38 mm
±0.25 mm
Atmospheric
pressure
For vertical shafts
29521
Excellent chemical
resistance.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
For upper installation in
vertical bearing housings.
Two o/d O-rings for
increased retention in
the bore.
Blue, glass-filled
PTFE, FDA quality*.
O-rings of fluoroelastomer are
standard.
-40°C to +200°C
23 m/s
±0.38 mm
±0.25 mm
Atmospheric
pressure
ISO-GARD®
Properties
Material
Without flange
29519
Excellent chemical
resistance.
Compliant with NEMA
MG 1-2003.
Surpasses IEEE 8412001 test standards.
Does not protrude
outside face of bearing
housing.
For split bearing housings
29516
SPECMA SEALS HANDBOOK
B E A R I N G I S O L AT O R S
ASSEMBLY INSTRUCTIONS
Garlock Guardian™ and Iso-Gard® bearing
isolators are supplied as a single unit.
It is not possible to remove the seal in
these components. Any attempts to do so
may damage the seal and invalidate the
warranty.
1. Disconnect all electric supply to the
equipment and follow all local safety
regulations.
2. Check the shaft and the surfaces of the
sealing area. Remove any burrs, marks or
scratches. Clean the surfaces to remove all
foreign particles.
3. Lubricate all O-rings using the special
lubricant supplied.
4. Push the seal carefully over the free end
of the shaft.
5. If the seal has a drainage channel, the
opening must be placed in the “six o'clock”
position.
6. Then manually push the seal into the
sealing area. If necessary, tap the seal in
carefully using a tool with a soft surface.
Check that the seal is pushed all the way to
the contact surface of the housing.
7. Never exceed the bearing housing's oil
level, and do not plug the drainage channel.
169