Drill feed depends on the tool, material, diameter, depth, and coolant delivery. Kennametal’s HP Beyond product page provides a diameter-based feed range for one selected through-coolant, solid-carbide B224 HP3×D drill in material group P steel. The table below keeps that scope visible and lists only the diameters and feed ranges given by the manufacturer.

Kennametal HP Beyond drill feed rates by diameter

Read the feed values correctly

Feed is shown in millimeters per revolution (mm/rev). At a 10 mm diameter, the manufacturer’s range is 0.15–0.33 mm/rev. The same product page specifies a 240 m/min starting cutting speed for steel material group P, within its listed 140–290 m/min range. These are paired recommendations for the named tool family, not a general feed chart for every twist drill.

To convert feed per revolution to table feed, multiply by spindle speed: Vf = f × n. If a 10 mm drill runs at 7,640 rpm for the 240 m/min starting speed, a feed of 0.15 mm/rev corresponds to about 1,146 mm/min. That is only a worked conversion. Actual spindle speed and feed must respect the exact material, drill length, machine, holder, hole depth, and coolant capability.

Choosing the applicable setup

First confirm the drill is the B224 HP3×D family and that the hole depth and through-coolant arrangement match the intended use. Then identify whether the workpiece belongs to the manufacturer’s P steel group and determine its hardness and condition. Steel group P is broad; alloy, hardness, tensile strength, and chip behavior can shift the appropriate setting within the range. Consult the full current Kennametal Tool Guide for the exact material and application.

For a blind hole, confirm chip evacuation and coolant access. A deeper hole, long overhang, interrupted cut, poor runout, or limited machine rigidity may require a conservative starting point and process adjustments. Watch chip shape and machine load during a controlled first hole. The table cannot tell whether a particular setup will produce the required diameter, finish, or tool life.

Two common mistakes

One mistake is reading mm/rev as mm/min. The feed range is per spindle revolution; multiply by rpm to calculate linear feed. Another is using the maximum feed with the maximum speed without checking the material and setup. The product page lists a range, not a guaranteed optimum or an instruction that every combination is safe.

Source: Kennametal HP Beyond B224 HP3×D drill product data. Use current manufacturer recommendations for final process selection.

Set up a controlled first hole

For production, start with the exact tool and material combination identified in the Kennametal guide, then confirm that the machine can provide the required through-coolant pressure and flow. Check runout at the tool, holder cleanliness, workholding, and the programmed depth before cutting. If the tool maker provides a narrower recommendation for the known alloy or hardness, use that more specific recommendation.

Feed and speed should be changed deliberately. If chips do not break or evacuate, review the hole depth, coolant delivery, and drilling cycle before simply increasing feed. If the machine vibrates or spindle load rises unexpectedly, stop and inspect the tool and setup. The table is a starting reference and cannot predict every machine’s rigidity or the condition of a particular workpiece.

For a through hole, plan the exit so the drill does not break through into a fixture or unsupported edge. For a blind hole, verify that the usable flute length and the 3×D drill geometry are appropriate. A short-hole tool should not be treated as a deep-hole solution just because its diameter matches.

When comparing a trial with the table, use the same units and record actual rpm rather than relying on a rounded speed display. Small differences in controller rounding are normal, but a factor-of-25.4 unit error is not. Check programmed feed and feed override before judging the tool-maker range.