Sprocket 12B-3 (3/4") z=20 with hub, C45 steel

Product Description

Sprocket 12B-3 (3/4") z=20 with hub, C45 steel fits 12B-3 roller chain (European standard DIN 8187 / ISO 606), triple-strand (triplex), with a pitch of 19.05 mm (3/4"). It has 20 teeth and is made of C45 steel.

The sprocket has a one-sided hub with a diameter of 100 mm and a pilot bore of Ø20 mm, which is bored to the shaft size and completed with a keyway or a set screw hole. The total width of the sprocket is 70 mm.

Technical data

Applications

It works in food and packaging industry machinery and in internal transport equipment. The triple-strand version is chosen for very heavily loaded drives where there is no room for a chain with a larger pitch.

Frequently asked questions

Which chain does the 12B-3 z=20 sprocket fit?

12B-3 roller chain to European standard DIN 8187 / ISO 606, with a pitch of 19.05 mm. A triplex sprocket requires a triple-strand (triplex) chain.

Does it fit ASA 60 chain?

No. ASA 60 chain (American standard) has the same pitch, but a different roller diameter (11.91 mm instead of 12.07 mm) and a different inner width (12.7 mm instead of 11.68 mm). The 12B sprocket is designed for European-standard chain, so the two systems should not be mixed.

How is a keyway cut in the hub?

The keyway is made to DIN 6885, keeping it aligned and with the correct width and depth so that the key sits firmly. The key should fit accurately - play in the keyway accelerates wear and, under shock loads, can lead to the key shearing off.

What is the set screw hole in the hub for?

The threaded hole, usually made above the keyway or at 90° to it, takes a headless set screw. It prevents the sprocket from sliding along the shaft when the machine vibrates.

Can a sprocket with hub be welded to the shaft?

Technically it is possible, but we do not recommend it. Welding overheats the material, can bend the shaft and damage nearby bearings, and makes later replacement of a worn sprocket very difficult. It is better to fix the sprocket with a key.

What does the lead time depend on?

When ordering, please check the current stock level of this sprocket - the lead time depends on it and is clearly stated according to the quantity available in each warehouse. The stock level is shown above the product price and may vary depending on the warehouse.

Product photos are for illustration purposes only.