Rubber and polyurethane hydrocyclone liners serve fundamentally different applications. Rubber excels in high-impact, coarse-particle environments where elasticity is critical. Polyurethane provides consistent wear resistance in fine-particle, lower-impact classification duties with superior chemical resistance and faster replacement times. The hidden costs — peeling failure, thermal aging, chemical attack, and replacement labor — often make rubber more expensive on a cost-per-ton basis despite lower upfront price.