Sprocket 20B-1 z=38 with hub, Cast iron

Product Description

Sprocket 20B-1 z=38, with cast iron hub

Sprocket 20B-1 (pitch 1 1/4" - 31.75 mm), simplex, 38 teeth, with hub. 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

How does uneven tooth wear affect machine vibration?

Worn teeth cause the so-called polygon effect - the chain drops off and climbs onto the teeth abruptly, which transmits vibrations to the shafts, destroys the bearings and leads to cracking of welds in the machine.

How can you recognise a sprocket not made in accordance with the DIN 8187 profile?

Most often it is visible from the incorrect seating of the chain on the teeth - the chain "sits" on the tooth tips or too deep in the tooth roots, despite the correct pitch. In that case, it is worth placing a section of a known reference chain of this pitch on the sprocket and checking whether it engages each tooth evenly and smoothly.

How do I check the radial and axial runout of a sprocket after mounting it on the shaft?

A dial indicator on a magnetic stand is used for the measurement. Place the tip against the circumference of the sprocket or its side face, rotate the shaft and check the deviations. Excessive runout indicates faulty installation or a damaged shaft.

How do I bore the hole in a sprocket to fit a motor shaft?

A sprocket with a pilot bore should be clamped in a lathe (gripping the hub to avoid runout) and bored to the required diameter with an H7 tolerance. The hub is usually soft and easy to machine, even in the version with hardened teeth.

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.