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8-471 BLACK FKM 90D BACK-UP RING

Viton® Back-Up Ring, 21.955 in ID x 0.275 CS, 90A, Black, -15 to 400°F

Status
Out of Stock
Est. Ship Date
20 Oct 2026
Material
Fluoroelastomer (FKM/Viton)
Dash Size
471
Durometer
90 Shore A
Cross Section Type
Round
Color
Black
Minimum Temperature
-15°F (-26°C)
Maximum Temperature
400°F (204°C)
Nominal Cross Section
1/4 inch
Nominal Inside Diameter
22 inch
Nominal Outside Diameter
22 1/2 inch
Unit of Measure
EA
SKU:
VBU90471

Product Specification

-
This back-up ring is supplied in AS568-471 black Viton® (FKM) 90 Shore A measuring an inside diameter of 21.955 in (557.66 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 22.505 in (571.63 mm), catalogued under part number VBU90471. It installs on the low-pressure side of an o-ring to prevent extrusion into the clearance gap at elevated pressure.

Viton® (FKM) is widely chosen for outstanding high-temperature capability and long service life in hot, chemically aggressive environments. It resists engine and transmission fluids, aggressive chemicals, and petroleum oils and fuels. Service temperature is rated from -15°F (-26.1°C) through 400°F (204.4°C). It is not the right choice where low-molecular-weight organic acids or amines are present.

Typical settings include aerospace, semiconductor equipment, and automotive fuel systems.

Order part number VBU90471, sold individually. Application requirements vary, so validate compatibility with your process conditions prior to installation.
Item
VBU90471
Description
8-471 BLACK FKM 90D BACK-UP RING
Actual Cross Section
0.275 inch (6.99 mm)
Actual Inside Diameter
21.955 inch (557.66 mm)
Actual Outside Diameter
22.505 inch (571.63 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6002
Product Category
O-Rings - Backup Rings