Part number SV70128 is an AS568-128 black Viton® (FKM) 70 Shore A Square-Cut Ring supplied with an inside diameter of 1.487 in (37.77 mm), a cross section of 0.103 in (2.62 mm), and an outside diameter of 1.693 in (43 mm). A square-cut ring seals with a broad flat contact band instead of the line contact of a round-section ring.
Viton® (FKM) is specified here for very low compression set at elevated temperature, excellent resistance to compression set and permeation. The compound resists chlorinated solvents, engine and transmission fluids, and many acids. Continuous operating temperature is published at -15°F (-26.1°C) to 400°F (204.4°C). It should not be specified for service in hot water and steam or amines. The profile itself contributes a flat contact band that spreads sealing load across a wider area and simple lathe-cut manufacture at low tooling cost. Note that a square section is less suited to high-speed rotary service, where the larger contact area raises friction and heat.
Common environments for this compound include oil and gas, chemical processing, and high-temperature process equipment.
Order part number SV70128, sold individually. Review your operating media and conditions against this specification before installation.
Description -128 BLACK FKM 70D SQUARE RING
Actual Cross Section 0.103 inch (2.62 mm)
Actual Inside Diameter 1.487 inch (37.77 mm)
Actual Outside Diameter 1.693 inch (43 mm)
Measurement System Imperial
Product Category O-Rings - Square/Quad - Commodity