Sprocket 28B-1 (1 3/4") z=19 with hub, steel, hardened teeth

Product Description

Sprocket 28B-1 (1 3/4") z=19 with hub, steel, hardened teeth works with 28B-1 roller chain (European standard DIN 8187 / ISO 606), single-strand (simplex), with a pitch of 44.45 mm (1 3/4"). It has 19 teeth and is made of structural steel. The teeth are induction hardened to 45-55 HRC, so they withstand wear from the chain rollers better. The hub is not hardened, so the bore can easily be machined to the shaft size.

The sprocket has a one-sided hub with a diameter of 160 mm, welded to the plate, and a pilot bore of Ø30 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 75 mm.

Technical data

Applications

It is found in transmissions of industrial machinery that transfer high torque.

Frequently asked questions

Which chain does the 28B-1 z=19 sprocket fit?

28B-1 roller chain to European standard DIN 8187 / ISO 606, with a pitch of 44.45 mm. A simplex sprocket requires a single-strand (simplex) chain.

Does hardening make machining the hub bore difficult?

No. Only the teeth are induction hardened (45-55 HRC); the hub remains unhardened. The bore can be machined to the shaft size and fitted with a keyway or a set screw hole.

Does it fit ASA 140 chain?

No. ASA 140 chain (American standard) has the same pitch, but a different roller diameter (25.4 mm instead of 27.94 mm) and a different inner width (25.4 mm instead of 30.99 mm). The 28B sprocket is designed for European-standard chain, so the two systems should not be mixed.

How do I check the pitch of a sprocket?

The sprocket pitch matches the chain pitch - it is the distance between the centres of adjacent teeth measured on the pitch circle. The easiest way to check it is to place a section of matching chain on the sprocket: it should sit on the teeth without tension. This sprocket has a pitch of 44.45 mm (1 3/4").

How is the pitch diameter of a sprocket calculated?

The pitch diameter Dp is the circle along which the chain rollers travel. It is calculated with the formula: pitch divided by the sine of (180° / number of teeth). For this sprocket it is 270.06 mm, and the outside diameter De is 289 mm.

When should I choose a sprocket with hub and when a plate wheel?

A sprocket with hub is chosen when it transmits torque directly from the shaft via a key - the hub provides a longer contact surface with the shaft and a more stable fit. Plate wheels are used mainly when the wheel is fixed to an existing flange or drum, or when there is little space on the shaft.

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.