Spindle Size Selection Chart Examples

Chart Based on the Following ProMetrixSpindle Characteristics:

1. ProMetrix Standard Spindle Series2.Tool overhang from spindle nose 3.Independent of housing type. Based on kW vs. RPM plus tool overhang.
Note: As a general rule the spindle nose bearing bore should be approximately as large or larger than the bore to be machined. If tool overhang is greater than the maximum allowed for a spindle size, go to the next largest spindle to accommodate tool overhang. Example No. 1: Customer’s boring operation (50.00mm bore) requires 22 kW at 5000 RPMwith 125.0mm tool overhang.Selection Procedure: 1.Locate 5000 RPM on the chart and follow this line until it intersects 22kW (it is within the 060-050 Spindle Size).2.Locate 125.0mm tool overhang on the chart and follow until it intersects the 060-050 Spindle line. This intersection falls within the180mm tool overhang limitation of a 060-050 spindle.3.Check to make sure the front bearing of the spindle is greater than or equal to the borebeing machined (60mm > 50mm).4.Therefore a 060-050 spindle is recommended for the customer’s operation. Example No. 2: Customer’s end milling operation (50.0mm end mill diameter) requires 4 kW at 500 RPM with 100.0mm tool overhang.Selection Procedure: 1.Locate 500 RPM on the chart and follow this line until it intersects 4kW (it is within the 070-060 Spindle Size).2.Locate 100.0mm tool overhang on the chart and follow until it intersects the 070-060Spindle line. This intersection falls within the tool overhang limitation of a 070-060 spindle.3.Tool overhang is not applicable for traditional milling operations. 4.Therefore a 070-060 spindle is recommended for the customer’s operation. Example No. 3: Customer’s grinding operation (200.0mm grinding wheel) requires 3 kW at 3000 RPM. 1.Convert 3000 RPM with a 200mm grinding wheel to meters per minute (m/min). 2.Check that grinding operations m/min is within the grinding wheels manufacturer m/min specifications. 3.Locate 3000 RPM on the chart and follow this line until it intersects 3kW (it is within the 050-040 Spindle Size).4.Tool overhang is not applicable for traditional grinding operations. 5.Therefore a 050-040 spindle is recommended for the customer’s operation.
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