1. High Pressure Coolant DVD
The Influence of High Pressure Coolant on Process Optimization in Heat Resistant Super Alloys (HRSA)
High Pressure Coolant DVD
Sean Holt
Aerospace Application Manager
Sandvik Coromant

2. High Pressure Coolant DVD
Agenda
Introduction and history of High Pressure
Challenges in Machining
Operational differences
HPC System requirements, benefits & considerations
HRSA machining results & difference with other materials
Future trends & directions
Introduction & history – Why did the industry go this way? What are the needs from manufacturing?
Future trends & directions – What’s new – cyro, CO2, laser, oil mist versus coolant?

3. High Pressure Coolant DVD
The History of High Pressure Coolant (HPC)
500 (7250)
Ccoupling for UHPC
100 (1450)
VTL
Pressure bar (psi)
Multi-task
Machining center
Turning center
Standard coupling
1984
1990
1996
2007
2012

4. High Pressure Coolant Definitions
High Pressure Coolant DVD
High Pressure Coolant Definitions
High Pressure Coolant (HPC) up to 80 bar (1160 psi)
Standard option on most machines
Turning centers
Machining centers
Multi-task machines
Standard Coromant Capto® coupling
Standard Sandvik Coromant tools available
Ultra High Pressure Coolant (UHPC) over 80 bar (1160 psi )
Standard option for a few machine manufacturers
Limited to VTLs
Coromant Capto® coupling for UHPC
Tool holders only as special

5. High Pressure Coolant Definitions
High Pressure Coolant DVD
High Pressure Coolant Definitions
Pressure (p) Force per unit area
Pascal = N/m2
Bar = 0.1 MPa (14.5 psi)
Flow rate () Volume displaced per time unit
liter/min (gallons/min)
Velocity (w) Speed fluid moves through a tube
m/sec (ft/sec) Kk
()
(w)
HPC definitions
Pressure is force per area unit.
Pressure (p) is used to describe the influences on fluid and gas behavior. Measured in :
Pascal which is Newton per square meter (N/m2)
Bar, where 1 bar = 0.1 MPa
psi (pounds per square inch) where 1 bar = 14.5 psi
Flow rate () is the volume of coolant displaced per time unit Measured in :
Liters or gallons per minute
Fluid velocity (w) is the speed at which the fluid moves through a tube
Measured in :
Meters or feet per second

6. High Pressure Coolant Challenges in machining
High Pressure Coolant DVD
High Pressure Coolant Challenges in machining
Operation differences:
Turning – continuous single point
Cutting temperature
Chip control
Milling – interrupted multiple teeth
Chip formation
Cutter positioning
Re-cutting of chips – unsecure or short tool life
Drilling – continuous multiple teeth
Varying cutting temperature
hot periphery
tough center
Chip control and evacuation through flute
The challenges in turning:
- Accurately sighting the nozzle for the het to hit the right place
- Keeping a parallel, laminar jet to the cutting edge once leaving nozzle
- Channeling of high volume, high pressure through all machine interfaces into the nozzle

7. HPC – Machining Requirements

8. HPC – System requirements
Pump/machine
Pressure
Volume/flow rate
Filter
Tool
Nozzle diameter
Number of nozzles
Jet flow
Jet direction
System requirements
Today, many CNC machines have coolant supplies at pressures of 70 to 100 bar as standard or option with ample tanks and pumps. This is sufficient to incorporate HPC, which makes a noticeable difference to performance and results on more commonly used machining centers, turning centers, vertical lathes and multi-task machines. Standard equipment is sufficient with easy channeling of coolant to where the jet is applied.
Modular tooling is an essential basis also for HPC machining partly to ensure quick tool changes for minimizing machine stoppages, but also to help secure coolant connections and supply from the machine to cutting edge.
The modular quick-change tooling system Coromant Capto came to be the platform for the Jetbreak development and is today the basis for CoroTurn HP, the new standard high-pressure-coolant tooling for turning. It is ideal as it is designed with internal coolant supply and also well suited as the means with which to supply coolant at high pressure.
The main system requirements for adapting HPC successfully are :
- pressure
- volume and flow rate
- tool nozzle size and type.
Filtration of coolant is important to get rid of chips and abrasive particles– helps to provide wear on tools and machine parts - prolong the life of the equipment. A general recommendation is 5 to 25 microns filtration.

9. HPC – System requirements Principles
Reducing the area increases the velocity
Smaller outlet reduces the pressure and flow rate requirements to achieve a high velocity jet
Flow velocity w1
Principle of HPC
The principle behind the application of high pressure tooling is that by reducing the area of the tube that the coolant has to pass through increases the velocity of the coolant.
By using a smaller outlet (nozzle), a reduction is achieved on the coolant - passing through the tube at a certain constant velocity (w1) - that is to be delivered at a certain pressure and flow rate at the point that matters : the cutting edge (w2).
Flow velocity w1 w2

10. HPC – System requirements Flow requirement
High Pressure Coolant DVD
HPC – System requirements Flow requirement
 Flow expressed in m3/s
CD Nozzle efficiency
- 80% 20 to 300 bars ( psi)
- 70% 300 to 1000 bars ( psi)
n Number of nozzles
d Nozzle diameter (m)
p Pressure (Pa) - 1 bar ( Pa) psi (6895 Pa)
 Fluid density - for water and cutting fluids the density is ~ 1000 kg/m3
The larger the outlet area the greater the flow required to deliver a given pressure

11. HPC – Machining HRSAs

12. HPC – Turning applications Precision is the power
High Pressure Coolant DVD
HPC – Turning applications Precision is the power
Hydraulic wedge lifts the chip
Reduces temperature
Improves chip control
Coromant Capto® Normal coolant inlet
The coolant enters the tool through the normal coolant inlet and the Coromant Capto® coupling. No further installation required. The secret is the high precision jet nozzles positioned close to the insert cutting edge. The nozzles project a parallel, laminar jet to pre-defined target areas on the insert face edge. The coolant jets hit in between the top face of the insert and the chip and act like a hydraulic wedge to lift the chip. This shortens the contact length between the insert and the material to reduce cutting forces, lower the temperature and improve chip control.
High precision jet nozzles
Pre-defined target areas on the insert face

13. High Pressure Coolant DVD
HPC – Turning applications Inconel 718 (46HRC) -Total material removed (TMR)
Total material – Q (cm3)
Surface cutting speed –
Vc (m/min), ft/min
Insert ap fn
CNMX 1204A2-SM S05F
2.5 mm
0.3 mm/rev
CNMX 43A2-SM S05F
0.1 inch
0.012 inch/rev
With CoroTurn® HP 70 bars (1160 psi)
Metal removal +50 at same speed
Cutting speed +20% with same total metal removal
Lab tests show that
at the same cutting data: + 50% increase in tool life
cutting speed can be increased 20% (50 to 60m/min) and the HP can remove more material than normal pressure at 50m/min
This benefit is only available with CoroTurn HP – without an optimized solution harnessing the coolant it would be just a high pressure shower –compare putting hand under a tap or a shower – where do you feel the force?

14. HPC – Turning applications Inconel 718 (46HRC) - Chip control
High Pressure Coolant DVD
HPC – Turning applications Inconel 718 (46HRC) - Chip control
Insert vc
CNGG SGF1105
65 m/min
CNGG 432-SGF 1105
213 sfm
Normal Pressure
80 bar (1160 psi)
Cutting depth
ap (mm)
Cutting depth
ap (mm)
2.0
2.0
1.0
1.0
0.5
0.5
Feed
fn (mm/rev)
Feed
fn (mm/rev)
0.25
0.25
0.15
0.2
0.25
0.15
0.2
0.25

15. HPC – Turning applications Inconel 718 (46HRC) - Demonstration
High Pressure Coolant DVD
HPC – Turning applications Inconel 718 (46HRC) - Demonstration
Insert ap fn
CNGG SGF 1105
0.25 mm
0.15 mm/rev
CNGG 432-SGF 1105
0.01 inch
0.006 inch/rev
CoroTurn® HP normal pressure
CoroTurn® HP 80 bars, 1160 psi

16. HPC – Machining in the Future

17. UHPC – Turning applications The basic concept of the technique
High Pressure Coolant DVD
UHPC – Turning applications The basic concept of the technique
UHPC
HPC
Coolant inlet
The pictures illustrate the difference between the UHPC and HPC technique.
In a UHPC tool, coolant is supplied externally into the Coromant Capto® coupling.
UHPC blanks are prepared with four sealing seats, final design will determine if one or more will be drilled through for coolant supply.
HPC has internal coolant supply through the Coromant Capto® polygon as a standard tool.
UHPC tool - coolant supplied externally into the Coromant Capto® coupling
UHPC blanks - prepared with four sealing seats
bar ( psi)
HPC tool – internal coolant supply through Coromant Capto ® polygon
80 bar (1160 psi)

18. High Pressure Coolant DVD
UHPC – Turning applications
Effect on Inconel 718
Normal coolant – 3 mins
UHPC bar (3300 psi) – 3 mins
UHPC bar (2200 psi)
UHPC bar (4350 psi)

19. Summary HPC has seen significant improvements in the last few years
New technologies & methods have made machining in HRSAs more efficient
Benefits of using HPC in HRSA machining:
Improves chip control
Improves tool life
Improves cutting speeds