Timing pulley L075 z=21 for 3/4" (19.1 mm) belt, C45 steel, pilot bore

Product Description

Timing pulley L075 z=21 for 3/4" (19.1 mm) belt, C45 steel, pilot bore works with timing belts of the imperial L profile - pitch 3/8" (9.525 mm), belt width up to 3/4" (19.1 mm). The pulley has 21 teeth. It is made of C45 steel.

The pitch diameter is 63.67 mm and the outside diameter 62.91 mm. The pulley has a hub with a pilot bore Ø11 mm, which is bored out to the shaft size and completed with a keyway or a set screw hole. The flanges (Ø70 mm) guide the belt and stop it running off the pulley.

Technical data

Applications

Machine tool drives, woodworking machines, belt and roller conveyors, industrial automation equipment.

Frequently asked questions

Which timing pulley has the L075 profile, 21 teeth and a pitch diameter of 63.67 mm?

This is the timing pulley L075 z=21 for 3/4" (19.1 mm) belt, C45 steel, pilot bore. The outside diameter (over the tooth tips) is 62.91 mm. The pitch diameter is calculated as Dp = pitch × z / π = 9.525 × 21 / π.

Which timing belt fits this pulley?

A belt with the imperial L profile (pitch 3/8" = 9.525 mm) and a width of up to 3/4" (19.1 mm) - in the belt designation the width 3/4" is written as 075 (e.g. belt 300L075, where 300 is the belt length in tenths of an inch). A narrower belt of the same profile will also run correctly.

Does this pulley work with a metric T10 or HTD belt?

No. The L profile has an imperial pitch of 9.525 mm and a trapezoidal tooth shape, so it does not mesh correctly with metric belts (T, AT) or with HTD belts with rounded teeth. The pulley and the belt must have the same profile.

How do I prepare the bore for the shaft?

The pilot bore Ø11 mm is bored out on a lathe to the shaft size (usually to tolerance H7) and a keyway is cut to DIN 6885. The pulley is secured axially with a set screw in the hub. The maximum bore depends on the hub diameter (45 mm) - enough wall thickness must remain after machining.

How do I calculate the ratio of a drive with this pulley?

The ratio is the number of teeth of the driven pulley divided by the number of teeth of the driving pulley, e.g. 21 / 18 = 1.17. A timing belt drive has no slip, so the ratio is constant.

What are the flanges for?

The flanges guide the belt and prevent it from running off the pulley. In a typical drive it is enough for one of the two pulleys, usually the smaller one, to have flanges.

What does the lead time depend on?

When ordering, please check the current stock level of this pulley - 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 differ between warehouses.

Product photos are for illustration purposes only.