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Introducing Energy-saving Introducing Energy-saving Hydraulic Units Hydraulic Units

Introducing Energy-saving Introducing Energy-saving Hydraulic Units Hydraulic Units

March 2006March 2006Fujikoshi Corporation Fujikoshi Corporation For publication

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Features Features 40% Energy-savings Compact and Lightweight Quite, Low-surge Cool Operation Block Installation Possible Easy Maintenance

Compact Variable Volume Pump Unit

NSP Series

40% Energy Savings

Compared to Existing Model

40% Energy Savings

Compared to Existing Model

Perfect for Machine and Cutting Tools

8 cm 3/rev

10 liter tank

26 cm 3/rev30/40 liter tank

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Pump capacity cm3/rev 8.0 16.0 26.0Maximumpressure

setting(Full cut-off)

Mpa 7.0

Electric driveoutput kW 0.75，1.5 1.5，2.2 2.2，3.7

Tank capacity Lit 30，40

Installationspace mm 340×450

Estimated dry

mass(no options)

kg63

(30Ｌ，2.2kW)43

(10Ｌ，1.5kW)

ModelItem

NSP-*-*V0A* NSP-*-*V1A* NSP-*-*V2A*

8.0

10，20

300×400

NSP Unit Series NSP Unit Series

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NSP Unit Series NSP Unit Series

６６０㎜３２０㎜

NSP-30-37V2A3-12(NSP Unit 30-L tank)

NSP-30-37V2A3-12(NSP Unit 30-L tank)

NCP-60-3.7VD1A3-20(Existing Unit 60-L tank)

NCP-60-3.7VD1A3-20(Existing Unit 60-L tank)

Energy Savings and Cool Operation　mean the NSP Unit's

tank capacity is

less than 1/2 the hydraulic fluid

capacity. (Comparable

specifications)

Energy Savings and Cool Operation　mean the NSP Unit's

tank capacity is

less than 1/2 the hydraulic fluid

capacity. (Comparable

specifications)

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Pump: Increased mechanical efficiency

Pump: Increased mechanical efficiency

Pump: Increased volumetric efficiency

Pump: Increased volumetric efficiency

Electric drive: copper loss, iron loss

reduction effectiveness ratio characteristics

modification

Electric drive: copper loss, iron loss

reduction effectiveness ratio characteristics

modification

Energy Saving Configuration Energy Saving Configuration

Plate-S oil groove

Vane pushing force reduction

Side clearance

External drain reduction

Plate-HPressure factor adjustment

Internal leakage, external drain reduction

Plate-S oil groove

External drain reduction

Increased efficiency of electric drive

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(1) Reduced pressure losses (1) Reduced pressure losses

: Energy saving product

: Conventional product

Pushing force(Not in low-energy model)

(2) Lowered sleeve resistance (2) Lowered sleeve resistance

(1) Changed hydraulic fluid routing in vane back pressure chamber

(2) Modified plate pushing force (3) Eliminated plate impulse channel

No internal leaks from gasket

Energy savings: Increased pumping efficiency Energy savings: Increased pumping efficiency

Plate S hydraulic fluid channel through-flow Stopped

Lowered internal

resistance, reduced drain

volume.

Lowered internal

resistance, reduced drain

volume.

(3) Stopped internal leaks (3) Stopped internal leaks

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Energy savings: Increased pumping efficiency Energy savings: Increased pumping efficiency

"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)

"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)

About the drain...

Conventional unit's pump generated 2 l/min

NSP unit's pump generates 0.5 l/min

Pump pressure

Drain volume

Hydraulic pressure symbol

(pump)

Dwelling

1/4 drain volume

8

50

55

60

65

70

75

80

0 25 50 75 100 125

Teeth

Slot shape Open Closed

Accumulated

thickness

TeethCore back

Hoop width

Electric drive-polarity: 2.2 kW-4P Voltage-cycles: AC 200 V, 60 Hz

When pump is fully cut off (dwelling time load ratio)

Conventional model

Electric drive load ratio (%)

Electric drive efficiency

Energy saving model

(%)

Stator Stator

Energy savings: Increased electric drive efficiency Energy savings: Increased electric drive efficiency

1) Accumulated thickness reduced and iron loss suppressed. (Rotor) 2) Hoop width changed to stabilize magnetic field. (Stator)

10%Increased efficiency

10%Increased efficiency

Rotor Rotor Energy savings

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0.0

0.5

1.0

1.5

2 4 6 8

Conditions (dwelling)

Electric drive-polarity 2.2 kW-4P

Voltage-cycles: AC 200 V, 60 Hz

Voltage 6.0 Mpa

Energy savings: Increased electric drive efficiency Energy savings: Increased electric drive efficiency

Dwelling pressure - power consumption characteristics

40% down

Conventional hydraulic unit

NCP-60

NSP Unit

NSP-20

Reduced dwell time power consumption 40%.

Reduced dwell time power consumption 40%.

Dwell pressure (MPa)

Po

wer

co

nsu

mp

tio

n (

kW)

10

0

4

8

12

0 30 60 90 120 150 180 210 240 270 300

Time (sec)

Pow

er c

onsu

mpt

ion

(kW

)

15% energy(Comparison of all machines)

40% energy savings(Comparison of hydraulic units)

All machinesWhen using the

conventional hydraulic unit

All machinesWhen using the NSP

unit

NSP Unit

Conventionalhydraulic unit

Nachi Machine Evaluation (Machining Center) Nachi Machine Evaluation (Machining Center)

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0.0

1.0

2.0

3.0

4.0

0 10 20 30 40 50 60

Time (sec)

Pow

er c

onsu

mpt

ion

(kW

)

INV UnitNSP Unit

Discharging

2 sec

8 sec

Dwelling

Approximately 20% energy

savings during discharge

Approximately 5% energy

savings during dwell

Energy savings during cyclic

operation: 12%

(1) Power consumption comparison

* Hydraulic fluid used: ISO VG32* Hydraulic fluid temperature: 40 to 50˚C* Electricity: 2.2 kW * Voltage - frequency: AC 200 V - 60 Hz* Operating cycles: 2 seconds 8 seconds <Discharge> <Dwell> * Discharge settings: 28 L/min, 2.0 MPa(NSP Unit: 16 cm 3/rev)* Dwell settings: 0 L/min, 6.0 MPa

[Operating conditions]

Compared with inverter unit produced by other company 1Compared with inverter unit produced by other company 1

NSP Unit Saves More Energy NSP Unit Saves More Energy

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Description INV Unit NSP Unit Energysavings

Discharging(2.0 MPa) 1896 1490 406Dwelling(6.0 MPa) 615 550 65

Power consumption: W

1896 W1490 W

Power consumption compared with inverter unit produced by other company

Power consumption compared with inverter unit produced by other company

615 W550 W

Discharging

Dwelling

NSP Unit NSP Unit INV Unit INV Unit

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0

5

10

15

20

25

30

35

40

0 1 2 3 4 5 6 7　 MPa)圧力 （

　l/min

流量

（）

0

2

4

6

8

　l/min

ドレ

ン量

（）

Ⅱナチッコ

INVユニット

● Ⅱ 　　：ナチッコ 流量○ Ⅱ 　　：ナチッコ ドレン量■ INV 　： ユニット流量□ INV 　： ユニットドレン量

[Operating conditions] 　 * Hydraulic fluid used: ISO VG 32　 * Hydraulic fluid temperature: 45C　 * Voltage-cycles: AC 200 V, 60 Hz

(2) P-Q characteristics comparison

: NSP Unit Flow Capacity : NSP Unit Drain Capacity : INV Unit Flow Capacity : INV Unit Drain Capacity

Compared with inverter unit produced by other company 2Compared with inverter unit produced by other company 2

INV Unit

RPMs are stable, but drain flow is small

NSP Unit

RPMs are reduced as energy is saved because drain flow is minimal.

RPMs are reduced as energy is saved because drain flow is minimal. RPMs being reduced,

but drain flow is large

Flo

w (

l/min

)

Pressure (MPa)

Dra

in f

low

(l/m

in)

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(3) Pressure pulse

[Operating conditions]

INV Unit 3.0 MPa, when discharging INV Unit 6.0 MPa, when dwelling

NSP Unit 6.0 MPa, when dwelling NSP Unit 3.0 MPa, when discharging

0.41 MPa 0.30 MPa

0.44 MPa 1.07 MPa

Compared with inverter unit produced by other company 3Compared with inverter unit produced by other company 3

Pulse width

is small

Propagation of pulse to machine is reduced

Propagation of pulse to machine is reduced

* Hydraulic fluid: ISO VG32 *Hydraulic fluid temperature: 40 to 50˚ * Pump capacity: 16 cm3/rev*Electric drive: 2.2 kW *Voltage - frequency: AC 200 V, 60 Hz

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[Operating conditions] 　 * Hydraulic fluid used: ISO VG 32　 * Hydraulic fluid temperature: 40 to 50C　 * Voltage-cycles: AC 200 V, 60 Hz

Pump operatingconditions

NSP Unit INV Unit

t1Discharging

↓Dwelling (6.0 MPa)

0.002 0.002

t2Dwelling (6.0 MPa)

　 ↓Discharging

0.020 0.100

Flow recovery time: Effects machine cycle

Compared with inverter unit produced by other company 4Compared with inverter unit produced by other company 4

(4) Response characteristics

Time

Pressure

Dwelling

Discharging

Clamp and chuck

t2

t1

The NSP unit has a quick response time for flow recovery so machines can operate at a high cycle.

The NSP unit has a quick response time for flow recovery so machines can operate at a high cycle.

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0

20

40

60

0 1 2 3 4

Compared with inverter unit produced by other company 5Compared with inverter unit produced by other company 5

(5) Rising hydraulic fluid temperature (Over 4 hours dwelling continuously)

Unit

MeasurementNSP Unit INV Unit

Roomtemperature (℃)Temperature of

hydraulic fluid intank (℃)

37.2 43.2

Increase intemperature (℃) 11.2 17.2

26.0

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.

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.

[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: 26C

NSP Unit

INV Unit

Room temperature

Operating time (Hrs)

Be

ari

ng

Te

mp

era

ture

（℃）

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Compared with inverter unit produced by other company 6Compared with inverter unit produced by other company 6

(6) Power consumption comparison (estimated cost for standard cycle)Standard cycle calculation conditions Discharging 5 hours/day

Dwelling 17 hours/day

Stopped 2 hours/day

Annual 8000 hours operation

Comparison of conventional unit and NSP unitConventional

unit (kW)NSP unit (kW)

Powerdifference (kW)

Hourly cost savings

(1) (2) (2)-(1) (yen)

2.0 MPaDischarging 1.50 1.50 0.00 0.00

6.0 MPaDwelling 0.90 0.55 0.35 5.25

Comparison of INV unit and NSP unit

INV unit (kW) NSP unit (kW)Power

difference (kW)Hourly cost savings

(3) (2) (2)-(3) (yen)

2.0 MPaDischarging 1.90 1.50 0.40 6.00

6.0 MPaDwelling 0.61 0.55 0.06 0.90

Effect of energy savings for one year

(Nachi comparison)

\32,400\32,400

Effect of energy savings for one year

(INV Unit comparison)

\16,500\16,500

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Reference materialReference material

Effect of reduction in power consumption and CO2

kWh/year kWh/year

For 50 units (hypothetical)

　Tons/year Tons/year

　 　 　 　 　 0.733kg/Wh

Other company’sINV unit

NSP Unit

Reduction of 40 tons/year

Total reduction 54,500 kWh/year

Annual powerconsumption

CO2 emissions265 225

361,000 306,500

Annual operating time8,000 hrs

Oil-fired　thermal　powerequivalence

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