Lowest friction single-lip PTFE rotary shaft seal

SB20


Lowest friction single-lip PTFE rotary shaft seal

This machined low-torque seal lip design extends seal life within its pressure limits.  It is capable of handling extreme temperature, aggressive media, high surface speeds, 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, 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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