FC Bond Ball Test Mill | Sepor, Inc

FC Bond Ball Mill Index Test Apparatus


The FC Bond Mill was designed by F. C. Bond for use in determining the Bond Ball Mill Index, a measure of grindability and power required to mill various ores.  FC Bond Mills are used in laboratories throughout the world. A copy of Fred C. Bond’s Method of Crushing and Grinding for determination of the Bond Index is included with each mill. 

This Ball Mill can be used continuously or it can be used for any number of revolutions, according to the type of grind desired. The FC Bond ball Mill comes with table stand, motor, clutch, revolution counter, motor starter* and controls, 12″ diameter machined steel drum, 44-1/2 pounds of steel balls, receiving pan and hand screen pan.


All material used is Mild Steel – 1018


Shafts after weld .00005” on diameter (total – 1.4370 to 1.4375 dia.) tight slip fit bearing. Key way shaft .002 on diameter/width and .004 centerline. * Shafts threaded and screwed into end caps prior to weld and machined to size after weld.

Tube OD- Stock Diameter ID was stock at 12.030” diameter.

End caps to match tube OD within .10” and threaded to match shafts. End caps were made with a light press fit into body (tube).

Inside 12” dimension from end cap to cap- held within .100” on average.

Mounting plate was a match fit to OD of radius to tube prior to weld.

Doors were a match fit to tube so door radius and ID of tube radius matched each other within .015” after gasket was installed.

After weld, all parts were checked for concentricity using Standard Pillow Block bushings – all parts ran within .005” when checked with indicator – this is worst case –most check with .003”.

All parts are deburred and lightly sanded after weld.

Welded shafts to endcaps- to support bushing to end cap to end cap to barrel mounting plate fused inside of end caps and mounting plate welded “T” nut assembly.


Catalog Number Description Shipping Weight
Shipping Dimension
010E-124 FC Bond Mill, 220-440 V/3 Ph/60 Hz 550 52x38x72
010E-125 FC Bond Mill Extra Ball Charge 45 12x12x12
010E-126 FC Bond Mill, 380 V/3 Ph/50 Hz 550 52x38x72

*Unless otherwise specified, starters are supplied with 220 Volt Starter.

SEPOR, INC 718 N FRIES AVE. WILMINGTON, CA 90744  |  310 830 6601  |  Fax: 310 830 9336  |  info@sepor.com