Designed to meet ISO 606 and DIN 8187 international dimensional standards, these sprockets are for use with compatible ISO and DIN roller chain. They come machined to the shaft diameter size listed and are machinable up to the maximum shaft diameter size.

For technical drawings and 3-D models, click on a part number.

For DIN, ISO 05B Roller Chain (8 mm Pitch)
Number of Teeth	For Shaft Dia., mm	For Max. Shaft Dia., mm	OD, mm	Overall Wd., mm	Hub Dia., mm	Material	Specifications Met		Each
21	8	25	57.5	14	35	Steel	DIN 8187, ISO 606	0000000	000000

Metal Worms and Worm Gears

Worm and Gear Sold Separately

Worm gears use screw threads to make large reductions to shaft speed while transmitting motion at a right angle. They transmit motion from worm to gear and cannot be reversed. For gears and worms to mesh correctly, they must have the same pressure angle and pitch/module. These worms are compatible with plastic worm gears.

Speed ratio is the ratio by which output shaft speed is reduced. As speed decreases, torque increases.

Cast iron gears are strong and durable.

Bronze gears have low friction and dissipate heat better than cast iron gears to provide a long service life for both the gear and the worm. They’re also more corrosion resistant than cast iron gears.

Aluminum-bronze gears have excellent wear resistance.

For technical drawings and 3-D models, click on a part number.

Metric Worm Gears

Gear

										Hub
Module	Speed Ratio	Number of Teeth	Pressure Angle	Gear Pitch Dia., mm	For Number of Thread Starts	OD, mm	Face Wd., mm	Overall Wd., mm	For Shaft Dia., mm	Dia., mm	Wd., mm	Material	For Thread Direction	Teeth Heat Treatment	Teeth Fabrication		Each
Round Bore—Cast Iron
2.5	20:1	20	20°	50	1	57.5	22	36	12	35	14	Cast Iron	Left Hand	Not Hardened	Not Ground	000000000	000000
2.5	20:1	20	20°	50	1	57.5	22	36	12	35	14	Cast Iron	Right Hand	Not Hardened	Not Ground	000000000	00000
2.5	10:1	20	20°	50	2	57.5	22	36	12	35	14	Cast Iron	Left Hand	Not Hardened	Not Ground	000000000	00000
2.5	10:1	20	20°	50	2	57.5	22	36	12	35	14	Cast Iron	Right Hand	Not Hardened	Not Ground	000000000	00000
Round Bore—Bronze
2.5	20:1	20	20°	50	1	57.5	22	36	12	35	14	Bronze	Left Hand	Not Hardened	Not Ground	000000000	000000
2.5	20:1	20	20°	50	1	57.5	22	36	12	35	14	Bronze	Right Hand	Not Hardened	Not Ground	000000000	000000
2.5	10:1	20	20°	50	2	57.5	22	36	12	35	14	Bronze	Left Hand	Not Hardened	Not Ground	000000000	000000
2.5	10:1	20	20°	50	2	57.5	22	36	12	35	14	Bronze	Right Hand	Not Hardened	Not Ground	000000000	000000
Round Bore—Aluminum-Bronze
2.5	20:1	20	20°	50	1	57.5	20	34	12	35	14	Aluminum-Bronze	Right Hand	Not Hardened	Not Ground	000000000	000000
2.5	10:1	20	20°	50	2	57.5	20	34	12	35	14	Aluminum-Bronze	Right Hand	Not Hardened	Not Ground	000000000	000000

Plastic Worm Gears

These plastic gears are lighter and quieter than metal gears—pair them with metal worms for lubrication-free operation. Worm gears use screw threads to make large reductions to shaft speed while transmitting motion at a right angle. They transmit motion from worm to gear and cannot be reversed. For gears and worms to mesh correctly, they must have the same pressure angle and module.

Speed ratio is the ratio by which output shaft speed is reduced. As speed decreases, torque increases.

Nylon gears are lightweight and stronger than acetal gears.

For technical drawings and 3-D models, click on a part number.

													Hub
Module	Speed Ratio	Number of Teeth	Pressure Angle	Gear Pitch Dia., mm	For Number of Thread Starts	OD, mm	Face Width, mm	Overall Width, mm	For Shaft Diameter, mm	Material	Fabrication	Color	Diameter, mm	Width, mm	For Thread Direction		Each
Round Bore
2.5	10:1	20	20°	50	2	57.5	22	36	12	Nylon Plastic	Molded	Blue	35	14	Right Hand	00000000	000000
2.5	20:1	20	20°	50	1	57.5	22	36	12	Nylon Plastic	Molded	Blue	35	14	Right Hand	00000000	00000

13 Products

About Roller Chain and Sprockets

About Gears

Sprockets for Metric Roller Chain

Metal Worms and Worm Gears

Plastic Worm Gears