Main Pressing Cylinder Main Pressing Cylinder
10.20 Flow Flow control control circuits circuits
10.20 Flow Flow control control circuits circuits
Meter-in type Meter-in type
circuit:-In meter-in type of circuit we co
In meter-in type of circuit we control flow of oilntrol flow of oil enterin
entering on g on actuator.actuator.
Q
Q = Pum= Pump output (LPM)p output (LPM) Q
Q11= Fluid volume (supplied = Fluid volume (supplied to actto actuatouator)r) Q
Q22 = Flui = Fluid volume returning to d volume returning to tank (throtank (through relief ugh relief valve)
valve) P
P = Pum= Pump pressure (kg/cp pressure (kg/c22)) P
P11 = Back-pressure = Back-pressure in
in actuator actuator due due to to resistanceresistance A
A11 = Area of cyli = Area of cylinder (cnder (cmm22)) Loss o
Loss of energy in Mf energy in Metereter-in-type will b-in-type will bee Le
Meter out type Meter out type circuit:-In meter-out
In meter-out type of circuitype of circuit we cot we control flntrol flow oow of oilf oil exhastin
exhasting g (comig (comig -out) from actuator.-out) from actuator.
Q2 = Q-Q1
For same working presur
For same working presure and same setting of fe and same setting of flowlow contr
control valves, the energy loss is same in mol valves, the energy loss is same in meter-eter-inin and meter-out circuit.
In bleed-off circuit by by-pass extra oil to rcuit by by-pass extra oil to tank.tank.
F
Loss of energy =
Loss of energy = PPxxQQ22
In bleed-off type circuit the loss o
In bleed-off type circuit the loss of energy is lf energy is lessess than meter-in or meter-out t
than meter-in or meter-out type of circuiype of circuit.t.
Many tim
Many time diffe different speed erent speed of actuatof actuator reor requiredquired using single pump. In such
using single pump. In such situation fosituation follllowingowing circuits are used dep
circuits are used dependinending og on requirementn requirement
Figure No 10.20.1 Study of Hydraulic Circuit
Study of Hydraulic Circuit
“Design and
“Design and Manufacturing of HydrManufacturing of Hydrauliauli c Pressc Presses.” es.” ©: Q.S. Kh©: Q.S. Khanan
F F A1
A1 TWO SPEED CIRCUITTWO SPEED CIRCUIT
1
4) Two speed circuit:wo speed
circuit:--In this circuit we have option of having full In this circuit we have option of having full speed,
speed, which we achieve by bywhich we achieve by by-passing flow-passing flow contro
control vall valve. Or we can have controlled speedve. Or we can have controlled speed by
by usiusing ng flflow ow contcontrol rol valvalve. ve. DiDirectirection on controlcontrol valve No.2 we use fo
valve No.2 we use for by-passing or blockingr by-passing or blocking the flow
M In neutral poIn neutral position of direction control valvesition of direction control valve No.2. W
No.2. We have speed as per settine have speed as per setting of flg of flowow contr
control valve nol valve number - FVumber - FV11 .And when direc- .And when direc-tion cont
tion control valvrol valve No.2 e No.2 is energiis energised then wesed then we have speed as
have speed as per combiper combined setting oned setting of FVf FV11&&
FV FV22..
5) T
5) Two control speedwo control speed:- :-In previous circuit we had
In previous circuit we had one full speed andone full speed and second contro
second controlllled speed. But if we want toed speed. But if we want to have two controlled
have two controlled speed then folspeed then followng cir-lowng cir-cuit is used. Study of Hydraulic Circuit
Study of Hydraulic Circuit
Functioning of two speed circuit
Functioning of two speed circuit (In this circuit bot(In this circuit both the speed ch the speed could be adjusted).ould be adjusted).
In this circuit we have used meter-in In this circuit we have used meter-in type fl
type flow-cow-controontrol vall valves. Tves. To have two speo have two speeded of actuator we have used one more flow of actuator we have used one more flow cont
control valve along with a solenoid valve inrol valve along with a solenoid valve in parall
parallel el with fwith first first flow control low control valvvalve. Samee. Same arrangement can be used for meter-o
arrangement can be used for meter-out as wellut as well as Bleed-off circuit.
Status of Pressure in Neutral Position Status of Pressure in Neutral Position
after forward stroke after forward stroke
Forward stroke. Study of Hydraulic Circuit
Study of Hydraulic Circuit
“Design and
“Design and Manufacturing of HydrManufacturing of Hydrauliauli c Pressc Presses.” es.” ©: Q.S. Kh©: Q.S. Khanan
•• WWhheen S3 n S3 & S4 & S4 arare ie in sn swwiitctch oh offf f conditi
condition , we get on , we get speed as per FV1.speed as per FV1.
•• WhWhen en S3 S3 enenerergigisesed, wd, we gee get spt speeeed ad as pes per r FV2.
FV2.
•• WhWhen en S4 eS4 ennerergigisesed , we d , we geget spt speeeed as d as peper r FV3.
FV3.
FV1 FV1
FV2 FV2
1
1 22 33
Q Q
M M
F F A1
A1 S3
S3
S4 S4
Q Q FV 1
FV 1
FV 2 FV 2
FV 3
FV 3 MM
•• ThreThree speed ale speed also coulso could be achid be achieved beved by usiy using fng folollowilowing cing circuircuit diagt diagramram..
6)
6) Three Three speed speed circuit:- circuit:-In this circuit first speed is full
In this circuit first speed is full speed wspeed without ithout any contrany control; second spol; second speed is as per flow contreed is as per flow control valveol valve FV
FV11. and t. and third speed is as per combined setting of FVhird speed is as per combined setting of FV11& & FVFV22. This manupulation we are able to. This manupulation we are able to do by using special
do by using special valvevalve. (Mod. (Model No, UCF2-04) made by M/s. Yel No, UCF2-04) made by M/s. Yuken India uken India Ltd.Ltd.
•• IIn n ffiirrsst t ppoossiittiioon n wwe e bbyy--ppaasss s FFVV11& & FVFV22. Hence get ra. Hence get rapid speed (full pid speed (full speed)speed)
•• IIn n ppoossiittiioon n 2 2 wwe e bbyy--ppaasss s FFVV22. Hence get . Hence get medium medium speed as per speed as per setting of FVsetting of FV11..
•• In In 3 r3 rd d poposisititionon, w, we e geget st spepeed ed as as peper r ccomombibinened sd setettitinng og of f FVFV11& & FVFV22..
10-52 10-52
Flow Control Circuits Flow Control Circuits Study of Hydraulic Circuit
Study of Hydraulic Circuit
S
S11 OONN -- SSlloow w ssttaarrt t ((FFlloowws s aas s ppeer r FFVV11.).) S
S33 OONN -- FFuulll l ssppeeeed d ((FFlloowws s aas s ppeer r FFVV11.+ FV.+ FV33.).) S
S33 OOFFFF -- SSlloow w ssttoop p ((FFlloowws s aas s ppeer r FFVV11.).) S
S11 OOFFFF -- SSttoopp S
S22 OONN -- SSlloow w rreettrraaccttiioon n ((FFlloowws s aas s ppeer r FFVV22.).) S
S44 OONN -- FFaasst t rreettrraaccttiioon n ((FFlloowws s aas s ppeer r FFVV22.+ FV.+ FV44.).) S
S44 OFOFFF -- SSlloow w ccoommpplleettiioon n of of rreettrraacctition on ((FFllowows s aas s ppeer r FFVV22.).) S
S22 OOFFFF -- CCoommpplleettiioon n oof f rreettrraaccttiioon n ((SSttoopp))
F F
S
S11 SS22 SS33 SS44
M M
FV1
FV1 FV 2FV 2 FV 3FV 3 FV 4FV 4
SLOW S
SLOW STTART ART AND STOAND STOPP, AND FAST MOVEM, AND FAST MOVEMENT CIRCUIENT CIRCUITT
To have slow start and stop and fast movement of actuator, we use folllowing circuit To have slow start and stop and fast movement of actuator, we use folllowing circuit diagram.
diagram.
Flow Control Circuits Flow Control Circuits Study of Hydraulic Circuit
Study of Hydraulic Circuit
“Design and
“Design and Manufacturing of HydrManufacturing of Hydrauliauli c Pressc Presses.” es.” ©: Q.S. Kh©: Q.S. Khanan
8)
8) Continuous speeContinuous speed control (Autometic sd control (Autometic speed control)peed control):- :-To have contin
To have continuous speed couous speed control as per the demand of process, we ntrol as per the demand of process, we have to use prohave to use proportionalportional electro-hydraulic flow control valve as per following circuit.
electro-hydraulic flow control valve as per following circuit.
10-54 10-54
Flow Control Circuits Flow Control Circuits Study of Hydraulic Circuit
Study of Hydraulic Circuit