Sprocket 20B-3 z=76 with hub, Cast iron

Product Description

Sprocket 20B-3 z=76, with cast iron hub

Sprocket 20B-3 with hub, 76 teeth, triplex (three-strand) - a product matched to chain with a pitch of 31.75 mm (1 1/4"). The material is grey cast iron - an economical solution with good vibration damping that proves itself in drives running at constant speed; the hub has a pilot bore that must be bored out individually to suit the shaft.

Technical data

Frequently asked questions

Does a larger number of teeth always mean a longer service life for the sprocket?

Largely yes - the more teeth are engaged, the lower the load on each individual tooth, and the chain runs over a larger wrap angle, which reduces dynamic impacts. Very small sprockets (with fewer than fifteen or so teeth) wear the fastest and are best avoided if the drive design allows.

When should I choose a sprocket with hub and when a flat one (plate wheel)?

Flat sprockets (plate wheels) are most often used where they are mounted onto an existing flange or drum, or when there is extremely little space on the shaft. We choose a sprocket with hub when it must reliably transmit high torque directly from the shaft via a key - the hub provides a longer contact surface.

How does one duplex sprocket differ from two independent simplex sprockets on a common shaft?

A duplex sprocket is a single, monolithic toothed rim serving a duplex chain, in which both strands are mechanically integrated in one component. Two independent simplex sprockets on a common shaft serve two completely separate simplex chains - these solutions are not interchangeable without changing the chain type.

Can a new chain be fitted on an old, worn sprocket?

Never do this. An old, deformed sprocket has altered tooth geometry and will force drastic mechanical stretching on the new chain. The rule is "new chain - new sprocket" - only then will the drive achieve maximum service life.

Does a cast iron sprocket require a different chain than a steel sprocket of the same pitch?

No - the tooth geometry and pitch are identical to those of the steel version of the same size, so the cast iron sprocket works with the same chain. The difference lies in the material of the hub and rim: cast iron dampens vibrations better and is cheaper, but withstands impacts and operation at high rotational speeds less well than steel.

Where is this product used?

20B-3 sprockets operate in drives of construction machinery, goods lifts, aggregate conveyors and woodworking machines - wherever tooth durability under load matters.

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.