This is an unused Martin SPH-31 shear pin hub. Shear pin sprockets provide simple, dependable protection against expensive machinery damage caused by overloads or jamming. Torque is transmitted by a single pin, necked to shear when the safe load is exceeded. When an overload occurs, the pin shears, disconnecting the drive immediately. This must be used with Martin SPA-31 to be mounted on a sprocket. Includes 3 shear pins.

This was removed from a large sprocket. Despite being removed, it was never mounted on machinery.

• Flange Thickness: 2.3125"
• Hub Assembly Type: Shear Pin Assembly 
• Hub Outside Diameter: 10.75"
• Hub Projection: 10.5" 
• Length Thru Bore: 12.9375" 
• Material: Cast Iron 
• Max Bore Size: 6.0000" 
• Min Bore Size: 5.5625" 
• Number of Bolts and Size: 2, 1 1/2 x 3/16" 
• Number of Set Screws and Location: 2 at bolts 
• Outside Diameter Flange: 22.5" 
• Part Inside Diameter: 5.5625" 
• Stocked Finished Bore: 5.5625"

Size listed (30 x 30 x 18) is shipping size.

Size/Weight listed is shipping size/weight.