HERCULES URETHANE BACKUP Ring 90A DUROMETER

Alternate Part Numbers
Alternate Part Number C1BV29, Alternate Part Number MI-01811171, Alternate Part Number MINO-00407Q30940
Brand
Hercules Sealing Products
Brand
Hercules Sealing Products
Pack Size
1.00
UOM
EA
Supplier Part Number
575-318
Product Weight
0.01 lbs

Product Questions & Answers

backup ring rated 90 durometer -- is that pretty stiff compared to what usually comes stock on most cylinders?
Question by: Tony C on Oct 24, 2025, 8:23 AM
Urethane at 90A durometer sits on the firmer end of the scale for backup rings. Stock seals often run softer, so swapping in a 90A urethane piece gives you better resistance to extrusion under pressure. For most hydraulic cylinder applications where fluid wants to push the primary seal out of its groove, that extra firmness is exactly what keeps the assembly holding together over time.
Answer by: Customer Support on Oct 25, 2025, 9:53 PM