Title: Introducing Energy-saving Hydraulic Units
1Introducing Energy-saving Hydraulic Units
March 2006
Fujikoshi Corporation
For publication
2Compact Variable Volume Pump Unit NSP Series
Features ? 40 Energy-savings ? Compact and
Lightweight ? Quite, Low-surge ? Cool
Operation? Block Installation Possible ? Easy
Maintenance
Perfect for Machine and Cutting Tools
26 cm 3/rev 30/40 liter tank
8 cm 3/rev 10 liter tank
40 Energy Savings Compared to Existing Model
3NSP Unit Series
4NSP Unit Series
Energy Savings and Cool Operation mean the NSP
Unit's tank capacity is less than 1/2 the
hydraulic fluid capacity. (Comparable
specifications)
660?
5Energy Saving Configuration
Increased efficiency of electric drive
Plate-S oil groove
External drain reduction
Pump Increased mechanical efficiency
Plate-H Pressure factor adjustment
Internal leakage, external drain reduction
Pump Increased volumetric efficiency
Electric drive copper loss, iron loss reduction
effectiveness ratio characteristics modification
Plate-S oil groove
Side clearance
Vane pushing force reduction
External drain reduction
6Energy savings Increased pumping efficiency
(1) Changed hydraulic fluid routing in vane back
pressure chamber
(1) Reduced pressure losses
Lowered internal resistance, reduced drain
volume.
(3) Eliminated plate impulse channel
(2) Modified plate pushing force
(3) Stopped internal leaks
(2) Lowered sleeve resistance
Plate S hydraulic fluid channel through-flow ?
Stopped
No internal leaks from gasket
7Energy savings Increased pumping efficiency
About the drain...
"Internal leaks" cause losses. However, they are
necessary to lubricate the pump. Too much Losses
(overheating, electrical power consumption) Too
little Burn out (sleeve resistance)
Hydraulic pressure symbol (pump)
Conventional unit's pump generated 2 l/min
1/4 drain volume
Drain volume
NSP unit's pump generates 0.5 l/min
Dwelling
Pump pressure
8Energy savings Increased electric drive
efficiency
Rotor
Energy savings
Stator
Electric drive efficiency
()
10 Increased efficiency
Electric drive-polarity 2.2 kW-4P
Voltage-cycles AC 200 V, 60 Hz
When pump is fully cut off (dwelling time load
ratio)
1) Accumulated thickness reduced and iron loss
suppressed. (Rotor) 2) Hoop width changed to
stabilize magnetic field. (Stator)
Electric drive load ratio ()
9Energy savings Increased electric drive
efficiency
Dwelling pressure - power consumption
characteristics
Conditions (dwelling) Electric drive-polarity
2.2 kW-4P Voltage-cycles AC 200 V, 60
Hz Voltage 6.0 Mpa
Conventional hydraulic unit NCP-60
Reduced dwell time power consumption 40.
40 down
Power consumption (kW)
NSP Unit NSP-20
Dwell pressure (MPa)
10Nachi Machine Evaluation (Machining Center)
11Compared with inverter unit produced by other
company 1
(1) Power consumption comparison
NSP Unit Saves More Energy
Operating conditions
Approximately 20 energy savings during discharge
Hydraulic fluid used ISO VG32 Hydraulic
fluid temperature 40 to 50C Electricity 2.2
kW Voltage - frequency AC 200 V -
60 Hz Operating cycles 2 seconds ? 8
seconds ltDischargegt ltDwellgt Discharge
settings 28 L/min, 2.0 MPa (NSP Unit 16 cm
3/rev) Dwell settings 0 L/min, 6.0
MPa
Energy savings during cyclic operation 12
Approximately 5 energy savings during dwell
12Power consumption compared with inverter unit
produced by other company
Power consumption W
Dwelling
Discharging
1896 W
615 W
550 W
1490 W
NSP Unit
NSP Unit
INV Unit
INV Unit
13Compared with inverter unit produced by other
company 2
(2) P-Q characteristics comparison
Operating conditions Hydraulic fluid used
ISO VG 32 Hydraulic fluid temperature 45?C
Voltage-cycles AC 200 V, 60 Hz
? NSP Unit Flow Capacity ? NSP Unit Drain
Capacity ? INV Unit Flow Capacity ? INV Unit
Drain Capacity
NSP Unit
RPMs are reduced as energy is saved because drain
flow is minimal.
Flow (l/min)
Drain flow (l/min)
INV Unit
RPMs being reduced, but drain flow is large
RPMs are stable, but drain flow is small
Pressure (MPa)
14Compared with inverter unit produced by other
company 3
(3) Pressure pulse
NSP Unit 3.0 MPa, when discharging
NSP Unit 6.0 MPa, when dwelling
0.30 MPa
0.41 MPa
Pulse width is small
Propagation of pulse to machine is reduced
INV Unit 3.0 MPa, when discharging
INV Unit 6.0 MPa, when dwelling
0.44 MPa
1.07 MPa
Hydraulic fluid ISO VG32 Hydraulic fluid
temperature 40 to 50 Pump capacity 16
cm3/revElectric drive 2.2 kW Voltage -
frequency AC 200 V, 60 Hz
Operating conditions
15Compared with inverter unit produced by other
company 4
(4) Response characteristics
Flow recovery time Effects machine cycle
Operating conditions Hydraulic fluid used
ISO VG 32 Hydraulic fluid temperature 40 to
50?C Voltage-cycles AC 200 V, 60 Hz
The NSP unit has a quick response time for flow
recovery so machines can operate at a high cycle.
16Compared with inverter unit produced by other
company 5
(5) Rising hydraulic fluid temperature (Over 4
hours dwelling continuously)
Operating conditions Hydraulic fluid used
ISO VG 32 Pump capacity 16cm3/rev Electric
drive 2.2 kW Voltage-cycles AC 200 V, 60
Hz Room temperature 26?C
INV Unit
It is possible to increase cutting precision
because the NSP Unit's hydraulic fluid
temperature increase is low so heat is not
transmitted to the machinery.
Bearing Temperature (?)
Room temperature
NSP Unit
Operating time (Hrs)
17Compared with inverter unit produced by other
company 6
(6) Power consumption comparison (estimated cost
for standard cycle)
Effect of energy savings for one year (Nachi
comparison)
\32,400
Effect of energy savings for one year (INV Unit
comparison)
\16,500
18Reference material
Effect of reduction in power consumption and CO2
19(No Transcript)