Extreme temperature low friction single-lip PTFE rotary shaft seal

SB20R


Extreme temperature low friction single-lip PTFE rotary shaft seal

This machined low torque seal lip design extends seal life within its pressure limits. A metallic thermal control ring provides dimensional control under thermal cycling conditions. It is capable of handling extreme temperature, aggressive media, high surface speed , low pressure and can even run dry. The soft seal OD eliminates damage to housings manufactured from expensive metals.  An integrated O-ring on the OD of the seal serves as an anti-rotation device and provides positive static sealing between the seal and the bore. Typical applications are dust/dirt excluders, balanced spindles, and conveyers. Small quantities are available in 2-4 days.




Operating Range
MaterialContinuous PressureMax.Pressure SpikeTemperatureSurface SpeedApplicationDry-runPV-Rating
Permachem 623330psi (2bar)40psi (2.7bar)-58 to 400°F (-50 to 200°C)Up to 10,000 fpm (50m/s)standard oil lubrication, high waterbased fluidsYES4.4
Permachem 623530psi (2bar)40psi (2.7bar)-58 to 400°F (-50 to 200°C)Up to 10,000 fpm (50m/s)Soft shaft material, gaseous media, FDA compliantYES4.4
Duraloy 473630psi (2bar)40psi (2.7bar)-58 to 400°F (-50 to 200°C)Up to 10,000 fpm (50m/s)low wear and abrasion, long service lifeYES4.4
Size Table (Inch)Standard Range sizes listed below are preferred sizes for new design applications; however, we offer any other seal size as required.Seals are available for any shaft diameter size in 0.001 inch increments, including Functional Range.
A
Shaft Diameter
CS
Cross-section

D
Bore Diameter
B
without
wiper lip +/- 0.010
B with
wiper lip +/- 0.010
L
F
C
R
Standard Range
Functional Range
Tolerance
*D=
Tolerance
B=
B=
+0.012/-0
+/-0.010
min.
max.
0.315 - 0.999"
0.315 - 5.000"
+/-0.003
1/4
A + 0.500
+/-.001
A + 0.030
A + 0.120
0.262
0.223
0.070
0.020
1.000 - 5.999"
0.315 - 18.000"
+/-0.003
3/8
A + 0.750
+/-.001
A + 0.030
A + 0.120
0.300
0.255
0.085
0.020
6.000 - 15.999"
0.500 - 26.000"
+/-0.004
1/2
A + 1.000
+/-.002
A + 0.035
A + 0.120
0.375
0.310
0.090
0.030
16.000 - 25.999"
0.500 - 26.000"
+/-0.006
5/8
A + 1.250
+/-.003
A + 0.040
A + 0.1200.512
0.425
0.100
0.030
26.000 - 63.000"
consult with Ahpseals engineering
*Standard cross-sections (CS) listed and non-standard sizes can be provided for any shaft size up to 63 inches. Surface finish: Shaft (A) plunge ground, zero lead Ra 6-12µin - Housing (D,L) Ra max.32µin - Shaft material hardness 55-65RC. Use of installation tool is highly recommended. See Technical Info for more specific information.

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