Sprocket 12B-2 z=76 with hub, Cast iron

Product Description

Sprocket 12B-2 z=76, with cast iron hub

Sprocket 12B-2, duplex, with 76 teeth and a hub - pitch 3/4" (19.05 mm). The sprocket is made of grey cast iron - a traditional material for sprockets in applications with moderate loads and lower rotational speeds; the bore in the hub is a pilot bore intended to be machined to the shaft size.

Technical data

Frequently asked questions

What does the pitch of a sprocket mean and how can it be checked?

The pitch of a sprocket corresponds to the chain pitch - it is the theoretical distance between the centres of adjacent teeth on the pitch circle. The easiest way to check it is to place a section of matching chain on the sprocket - it should sit perfectly, without tension.

How do you select the number of teeth on the driving and driven sprockets to obtain the required ratio?

The ratio is calculated as the quotient of the number of teeth on the driven sprocket and the number of teeth on the driving sprocket. For example, to halve the rotational speed, the driven sprocket should have twice as many teeth as the driving sprocket - both sprockets must have the same pitch and number of strands.

Does the machine's operating temperature matter when choosing the sprocket material?

Yes - at very low or very high temperatures the mechanical properties of steel or cast iron change, and lubricants may change viscosity or thicken. Under unusual thermal conditions (cold stores, furnaces, dryers), it is advisable to consult the supplier before selecting a specific material variant.

How can a sprocket and chain be protected against corrosion during storage?

After cleaning off any dirt, it is advisable to apply a layer of preservative grease or anti-corrosion oil and store the sprocket in a dry place not exposed to condensation. In the steel version (without coating), even a short damp break in the workshop can cause a rusty film on the tooth surfaces.

Is a duplex sprocket the same as a tandem sprocket (for two single chains)?

No, even though they look very similar. A tandem sprocket is also a single, monolithic sprocket, but with a different (wider) spacing of the toothed rims - designed specifically for two independent simplex chains running in parallel. This duplex sprocket has a rim spacing matched to a single duplex chain, in which both strands are integrated with each other. Using a duplex sprocket for two single chains is a mistake - the spacing is too narrow and the chains will rub against each other, which leads to accelerated wear and, in extreme cases, to serious drive failure.

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?

Applications include drives in the food industry, packaging machines, sorting lines and agricultural harvesting machines, where the sprocket operates seasonally but under full load.

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.