Каталог Iscar сверла ружейные и для глубокого сверления 2022 - страница 94

Предыдущая страница Следующая страница

Навигация

Coolant

Successful deep hole drilling is achieved by an STS - Double tube system optimal combination of the tool, the machine and

WorkpieceOuterDouble tube
the coolant. Coolant plays an essential role intubeconnector
material
achieving secure and cost-efficient deep hole drillingDrillGuide
operations. Therefore, it is very important to chooseheadbushInnerChip
the correct type of coolant and use it appropriately.tubebox

Coolant Coolant plays an essential role in lubricating tools, cooling cutting edges, chips and guide pads, as well as evacuating chips when drilling. It also improves No need for sealing

tool life, surface finish and cutting accuracy when continuously supplied during the machining process. Coolant unit A coolant unit is also important to obtain 1 Lubrication the best effect from the coolant. Lubrication of cutting edges and guide pads is necessary in deep hole drilling. For efficient lubrication, 1 Coolant pressure and volume should

it is recommended to use EP (Extreme Pressure)be fixed and continuous.
additives which contain sulfur or chlorine.
An ideal coolant unit should be able to set any valve of
coolant pressure and volume and monitor the condition
2 Temperature reductionwith gauges. A system that can detect trapped chips
The ability to cool down the cutting edge andby a pressure gauge and the screw pumps with
chips depends on such characteristics asan inverter controller are both recommended.
thermal conductivity and relative heat. Coolant
with good cooling ability increases tool life, but2 Coolant temperature should be maintained.
water-soluble coolant is not preferred in deep
Coolant is heated by factors, such as:
hole drilling because it reduces effectiveness. If
water-soluble coolant is used, the recommended• Cutting edge
concentration is 10% (dilution rate 1/10) or more.• Friction on guide pad
  • Contact time of heated chips and coolant
3 Chip evacuation• Pump
Maintaining coolant temperature is important to
Coolant helps push chips through the back end of thekeeping stable cutting conditions, chip formation
boring bar (for STS) or inner tube (for DTS) until the chipsand cutting accuracy. The temperature should
are separated from the workpiece in general cuttingbe lower than 40°C (100°F) for EP additives to
conditions. The flow and the pressure of coolant areprovide sufficient lubrication. Therefore, the coolant
also important in order to control chip evacuation.temperature should be kept between 30 - 40°C
STS - Single tube system (90 - 100°F) throughout the cutting operation.
Workpiece
material3 Filtering Oil
Guide

bush pressure Unwanted particles are contained in coolant after the

Drill Drill head Bar Chip

tube Sealing cutting operations, thus filtration is necessary to remove

head rest box

them. The filter size should be selected carefully to catch particles but not EP additives. Filter size depends on the coolant, but around 10 - 20 μm is generally suggested. For iron-based workpieces, a magnetic separator is helpful

as it decreases the frequency of filter maintenance.

Flow chart of coolant in deep hole drilling

Pressure gauge Flow gauge Motor

MPumpPM
Chipbreaker
P
Drill
headDrill tubeFilter
WorkpieceChiller
Oil
pressureChip

box Dirty tank Clean tank

head