Sprocket 12B-3 z=28 with hub

Product Description

Sprocket 12B-3 z=28, with hub

Sprocket 12B-3 with hub, 28 teeth, triplex (three-strand) - a product matched to chain with a pitch of 19.05 mm (3/4"). The material is C45E carbon steel (EN 10083-1), and the teeth remain unhardened (without induction hardening) - in accordance with DIN 8187 / ISO 606; this version is easier to machine over the entire depth of the sprocket.

Technical data

Frequently asked questions

What is the set screw hole in the hub for?

The threaded hole in the hub is used to screw in a headless screw (a so-called grub screw). It secures the sprocket against axial displacement along the shaft during machine vibration.

How does a sprocket differ from a module spur gear?

A sprocket works with a roller chain and has a tooth profile matched to the chain rollers (standard DIN 8187/ISO 606), whereas a module spur gear meshes directly with another gear or a gear rack, has an involute tooth profile and parameters described by the module (standard DIN 780/ISO 54). These are two different power transmission systems, not interchangeable with each other.

When does tooth wear (the "shark fin" profile) mean the sprocket must be replaced?

If the teeth resemble pointed, tilted shark fins, the sprocket must be replaced immediately. Operating on such a profile can damage even a brand-new chain within a dozen or so days.

Does the difference in hardness between sprocket and chain affect their rate of wear?

Yes - chain and sprocket manufacturers select hardness so that they wear as evenly as possible, rather than one element "cutting down" the other. An excessively hard sprocket working with a soft, non-certified chain (or vice versa) leads to faster wear of the weaker element.

Where is this product used?

This type of sprocket is used in drives of agricultural and industrial machinery, including screw and bucket conveyors, feed conveyors, packaging machines and internal transport systems.

When placing your order, please check the current stock level of this gear - the lead time depends on it and is clearly stated according to the quantity available in the given warehouse.

Product photos are for illustrative purposes only.