COMPACT ROTODIFF...HYDROSTATIC DRIVE SYSTEM FOR DECANTER CENTRIFUGES COMPACT ROTODIFF Operating Principle The COMPACT-ROTODIFF basically consists of a gear pump (R8), a flow control

HYDROSTATIC DRIVE SYSTEM FOR DECANTER CENTRIFUGES

COMPACT ROTODIFFOperating Principle

The COMPACT-ROTODIFF basically consists of a gear pump (R8), a flow control valve (R15), and a slow speed, high torque hydraulic motor (R1). These three elements form a compact unit, the Com-pact-Rotodiff, which is attached to the bowl. It is connected to the scroll with a splined shaft.The adaptation of this new COMPACT ROTODIFF, as a for the replacement of gearboxes both for new and existing machines, is very easy, due to its simple concept.

The rotating hydraulic motor (R1) drives the scroll. The pump (R8) drive shaft is supported outside of the rotating part. When the bowl rotates, the pump produces an oil flow proportional to the bowl speed, which is then divided by the flow control valve (R15). The output oil flow from the flow control valve, which is independent of the bowl speed and the load, powers the scroll drive motor (R1) with a constant differential speed. The excess oil flow from the pump (R8) is diverted to the oil return system.

The variation of the differential speed is obtained by changing the oil flow which is directed to the scroll drive motor (R1). This is done by an adjustment of the flow control valve. The flow control valve positioning is achieved by varying the backpressure of the return oil system, through an electronic proportional valve working with an amplifier. The regulation of the differential speed is, therefore, controlled by an electronic control unit (CVC etc.)

The oil return flow is passed over an air-blast oil cooler (P7) and a filter (P8), and then returned to the rotating assembly and the suction side of the pump (R8). An oil volume compensation bellows (P9) is used to allow for a slight pressurisation of the suction, adapt to temperature changes, and to produce a completely closed hydraulic system.

Operation measurements and signals are taken from:

• The torque of the pump shaft with a force sensor (R17). This torque, multiplied with the appro-priate factor, gives the torque of the scroll drive motor (R1) which is the scroll torque.

• The bowl speed with the speed pick-up sensor (R20).

• The scroll speed with the speed pick-up sensor (R19).

Neuhaus | 8132 Hinteregg-Zürich | Switzerland | Tel. +41 (0)44 986 28 00 | Fax +41 (0)44 986 28 28 | www.viscotherm.ch

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Tem

pera

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sw

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(P10

)

Forc

e se

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(P10

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Pro

port

iona

l val

ve (P

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Hyd

raul

ic m

otor

(R1)

C

OM

PAC

T R

OTO

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F

Leve

l sw

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(P11

)

Filte

r (P

8)

Vol

ume

com

pens

tion(

P9)


2

08/2

010


Cam

(R4)

Ste

p pi

ston

(R12

)

Pis

ton

(R4)

Rot

or (R

6)Fl

ow c

ontr

ol v

alve

(R15

)

Gea

r pu

mp

(R8)

Sta

tiona

ry s

haft

(R14

)

Forc

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(R17

)

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pera

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sw

itch

(P10

)

Sta

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art

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bloc

k (R

3)

Pro

port

iona

l val

ve (P

6)

Torq

ue a

rm (1

6)

Scr

oll s

peed

sen

sor

(R19

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owl s

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sen

sor

(R20

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Driv

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for

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Ret

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line


3

08/2

010

R1 R8R15

FI

R16

P9P8

P7

P6

R19

R20

R17

R2


Simplified Hydraulic Scheme

High pressure

Return line pressure

Pressure less

LegendR1 Hydraulic scroll drive motorR2 Bowl drive motorR8 Gear pumpR15 Flow control valveR16 Torque armR17 Force sensorR19 Scroll speed sensorR20 Bowl speed sensorP6 Proportional valveP7 Air oil coolerP8 FilterP9 Volume compenation


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010

Schluckvolumen PumpeDisplacement pump ccmVolumen de bomba

3600max. Arbeitsdruckmax. working pressure barmáx. presión laborable

250

Schluckvolumen ROTODIFF l/UDisplacement ROTODIFF l/tVolumen de absorbaci ón l/r

0.934Drehmoment bei 250 barTorque at 250 bar NmPar a 250 bar

3‘717

max. Hauptdrehzahl U/minmax. main speed rpmmáx. giros de tambor rpm

4‘500max. Druckmax. pressure barmáx. presión

280

max. Diff.Drehzahl bei4‘500 rpm Hauptdrehzahl U/minmax. diff.speed at4‘500 rpm maim speed rpmmáx. giros differenciales a4‘500 rpm de giros de tambor rpm

16

Drehmoment bei 280 barTorque at 280 bar NmPar a 280 bar

4‘163

GewichtWeight kgPeso

~39


TrademarkROTODIFF® and VISCOTHERM® are registered Trade marks of Viscotherm AG.

COMPACT ROTODIFF 5070 S


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Documents

COMPACT ROTODIFF...HYDROSTATIC DRIVE SYSTEM FOR DECANTER CENTRIFUGES COMPACT ROTODIFF Operating Principle The COMPACT-ROTODIFF basically consists of a gear pump (R8), a flow control