Hardened teeth on the smaller sprocket of a roller chain drive are recommended if the drive ratio is four to one or greater or if the smaller sprocket has 24 teeth or less and is running at a speed of over 600 rpm.
features
Hardened teeth sprockets afford longer chain and sprocket life
Tolerances meet or exceed ANSI standards
Manufactured of high carbon steel
Precise machining and processes ensure consistent finish and high quality
Chain rows are parallel and precisely spaced to increase longevity of sprocket and chain
Bores are concentric to pitch line, minimizing run out
Interchangeable with other manufacturers’ Taper bushings
Stocked Heat Treat
Bushing Series
2517
Inch/Metric
Inch
O.D.
7.235 in
Overall Length Less Threads
N/A
Hub Dia.
4 1/4 in
Hub Projection
1.19 in
Bushing Bore [Min]
1/2 in
Pitch Dia.
6.71 in
Chain Sprocket Number
80
Caliper Diameter
6.0657 in
Single Strand Tooth Thickness
0.575 in
Type
B
Construction Internal
Welded
Pitch Diameter
6.710 in
Sprocket Style
B
Chain No.
80
Chain Sprocket Pitch
1 in
No. of Strands Across
1
Overall Length
1 3/4 in
Bushing Bore Size [Max]
2.875 in
Bushing Type
Taper Lock
No. of Teeth Rows Strands
1
No. of Teeth
21
Outside Dia.
7.235 in
Chain Pitch
1.000 in
Tooth Width
0.575 in
Width Across Teeth
1.75 in
Material
Steel
Length Through Bore
1.75 in
Hub Length
1.19 in
Material Internal Use
Carbon Steel
Material External Use
Steel
Martin No.
80BTB21H
Bore Size [Max]
2.875 in
Hardened Teeth
With Hardened Teeth
Hub O.D.
4.25 in
Outside Dia. [Min]
7.2350 in
Bushing Bore [Max]
2 1/2 in
Bore Type
Bushed
Weight
5.8 LB
EAN or UPC
697950043609
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