Page 297 - ISCAR(HOLE_MAKING_CATALOG_65)

USER GUIDE
GUNDRILLS

Drill Penetration Instructions on Horizontal Pressure and Coolant Flow Rate for SUMOGUN
Milling and Lathe machines
Bar l/min
Note: The following procedure (1-4) is recommended for
up to 400 mm hole depths using MNSNT ...-400... drill. 120 300
275
110
1 Drill a pilot hole 0.5xD deep with a short drill in 100 250
the same diameter as of the SUMOGUN drill. 90 225
2 Enter the pre-hole at slow speed, feed and 50 80 200
RPM until 1-2 mm before reaching the bottom. 70 175
150
60
3 Activate the cooling system and increase rotation speed 50 125
to recommended drilling speed, maintain for 2-3 seconds, 40 100
then continue at recommended drilling feed. No pecking 30 75
is required. Apply maximum possible coolant flow rate. 20 50
25
10
4 After having reached the required depth, reduce
speed to 50-100 RPM while exiting from the hole. Ø 10 12 14 16 18 20 22 24 26 mm
SUMOGUN Drilling Range Drilling Diameter
SUMOGUN Drilling Range Drilling Diameter
1 Pre-hole 1xD deep for centering Q l/min P bar
GUNDRILL Machines
Milling and Turning Machines
Gundrill Lubrication and Cooling
The best performance is obtained by using oil.
On equipment that uses water-soluble fluids (i.e.
machining centers and CNC machines) a concentration
1xD between 10% and 15% is recommended.
2 Slow rotation and feed while entering to the pre-hole Guidelines for Optimal Gundrill Performance
• Coolant pressure and flow
• It is recommended to use a strong coolant flow for
efficient chip flushing and cooling of the cutting edge
• Filtration: It is recommended to use a filter under 20 µm.
• Note: Improper filtration may result in interrupted flow of
the lubricating oil. This creates a sticky surface on the
bearing pads and leads to premature wear of the tool
1xD and overloading the coolant pump and spindle seals.
• The coolant temperature should be between 20 and 22º C.
3 Maintain for 2-3 seconds and activate the cooling system Note: Above 50º C the viscosity of the coolant is reduced by 50% and
becomes ineffective.

1xD
4 Continue drilling at recommended cutting conditions

SUMOGUN

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