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The Ball Screw Accuracy Grade scale is divided into eight classes: Precision Grades - C0, C1, C2, C3, C4, C5, and the General Grades: C7 and C10. Higher the number, lower the accuracy grade.
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Precision application
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General application
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C0
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C1
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C2
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C3
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C4
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C5
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C7
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C10
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Higher grade ----------------------------------------------------------------------- Lower grade
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| The accuracy of a ball screw is defined by three major parameters, namely: Lead accuracy, Mounting interface accuracy, and Preload-torque variation in percentage. The JIS standards set forth the allowable values for each accuracy grade. |
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| (Example) A ball screw with C5 accuracy grade has: Lead accuracy of C5, Mounting interface accuracy of C5, and Preload torque variation percentage of C5 |
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Ball screw accuracy grade should be chosen to satisfy the positioning accuracy requirement of the applicable machinery system. Refer to our catalog data. Kuroda recommends the following guideline, based on our application experiences. |
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Type of machine
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Accuracy grade
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C0
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C1
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C2
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C3
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C4
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C5
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C7
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C10
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CNC machines
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Machining centers , Milling machines
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XY
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Z
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Lathes
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X
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Z
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Grinders
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X
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Z
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Electro-Discharge-Machines
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XY
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Z
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Punch Presses
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Wood working machines
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Industrial robots
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Cartesian-coordinate Type
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Articulated Arm Type
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SCARA Type
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Semiconductor manufacturing equipment
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Photoresist Exposure Systems, Masking Systems
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Etching, Ion Implantation Systems
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Wire bonders, Die bonders
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Wafer Probers
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PC board Assembly Systems
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Printing equipment
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Electronic color separating apparatus
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Electronic composing machines
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Business equipment
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Color graphic printers
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XY Plotters, Drawing Automation Systems
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Injection Mold Machinery
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Conveyors and Pick-and-Place Systems
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