12B (3/4") hardened hub sprockets

12B hardened hub sprockets work with 12B roller chain of 3/4" (19.05 mm) pitch to DIN 8187 / ISO 606. It is a popular size in agricultural machinery, conveyors and medium-sized industrial equipment, and the induction-hardened teeth significantly slow down sprocket wear.

12B hardened sprockets - fewer stoppages to replace the sprocket

Replacing a 12B sprocket in a machine usually means several hours of downtime - a hardened sprocket makes this happen less often. Teeth with a hardness of 45-55 HRC withstand abrasion well, and the tough C45 steel core absorbs shocks. The hub remains soft, so you bore the hole out for your shaft.

3/4 inch hardened sprockets: simplex, duplex and triplex

12B-1 simplex, 12B-2 duplex and 12B-3 triplex sprockets with hardened teeth - each version has its own subgroup. 12B sprockets with unhardened teeth can be found in the Hub sprockets group.

Questions and answers: hardened sprockets for 12B chain

Does a 12B sprocket fit ASA 60 chain?

No. ASA 60 (12A) chain has the same pitch, but a different roller and inner width. Sprockets for American chains can be found in the ASA sprockets group.

Which sprocket in the drive should be hardened first?

The driving sprocket, i.e. the smaller one. It makes more revolutions and each of its teeth engages more often, so it wears fastest.