5-p0921-0943-vba_en.pdf - 第8页

Tc Ts Pressure Stroke Upper limit of pressure inside the tank P 3 Inlet pressure P 1 Time Necessary supply pressure to cylinder P 2 Sizing ( ) END START NO NO NO YES YES YES YES YES When running continuously for longer p…

1.6

1.4

1.2

0.8

0.6

0.4

0.2

Outlet pressure (MPa)

0 500 1000 1500 2000 2500 3000

Outlet air flow rate (L/min (ANR))

1.08

1.06

1.04

1.02

1.0

0.98

0.96

0.94

Outlet pressure (MPa)

0 0.4 0.5 0.6 0.7 0.8 0.9 1

Inlet pressure (MPa)

0.1

0.08

0.06

0.04

0.02

Max. pulsation range (MPa)

0 1 2 3 4 5

Capacity (L)

0.1

0.08

0.06

0.04

0.02

Max. pulsation range (MPa)

0 10 20 30 4038

Capacity (L)

Charge time per 10 L t (s)

1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0

Pressure increase ratio P2/P1

400

300

200

100

Charge time per 10 L t (s)

1.0 2.0 3.0 4.0

Pressure increase ratio P2/P1

Outlet pressure (MPa)

0 0.4 0.5 0.6 0.7 0.8 0.9 1

Inlet pressure (MPa)

Outlet pressure (MPa)

0 100 15050

Outlet air flow rate (L/min (ANR))

2.1

2.05

2.0

1.95

1.9

1.85

1.8

Pulsation/Pulsation is decreased with a tank.

If the outlet capacity is undersized, pulsation may

occur.

Conditions:

Inlet pressure: 0.5 MPa

Outlet set pressure: 1 MPa

Flow rate: Between 0 and max. flow rate

•

Performance of air tank

• Alleviates the pulsation generated on the

outlet side.

• When air consumption exceeds air supply

during intermittent operation, required air

will be accumulated in the tank for use.

This does not apply for continuous

operation.

Flow-rate Characteristics

Charge Characteristics

Pressure

Characteristics

= 0.8 MPa

= 0.7 MPa

= 0.6 MPa

= 0.5 MPa

P1 = P2

VBAT05A

VBA43A

VBAT05A

VBAT10A, 20A, 38A

VBAT10A

VBAT20A

VBAT38A

VBA11A

Flow-rate Characteristics

Charge Characteristics

Pressure

Characteristics

Set point

= 0.4 MPa

= 0.5 MPa

= 0.75 MPa

= 1.0 MPa

P1 = P2

= 0.3 MPa

Inlet pressure: 0.6 MPa

Outlet pressure: 2.0 MPa

Flow rate: 10 L/min (ANR)

Inlet pressure: 0.7 MPa

Outlet pressure: 1.0 MPa

Flow rate: 20 L/min (ANR)



The time required to charge pressure in the

tank from 0.8 MPa to 1.0 MPa at 0.5 MPa

supply pressure:

With the pressure increase ratio from 1.6 to 2.0,

the charge time of 4.5 – 1.3 = 3.2 sec. (t) is

given by the graph. Then, the charge time (T)

for a 100 L tank:

0.8

0.5

= = 1.6 = 2.0

1.0

0.5

T = t x = 3.2 x = 32 (s).

100

= 2.0 = 3.0

T = t x = 89 x = 89 (s).



The time required to charge pressure in the

tank from 1.0 MPa to 1.5 MPa at 0.5 MPa

supply pressure:

With the pressure increase ratio from 2.0 to 3.0,

the charge time of 147 – 58 = 89 sec. (t) is

given by the graph. Then, the charge time (T)

for a 10 L tank:

1.0

0.5

1.5

0.5

Booster Regulator Series VBA

(Representative

value)

(Representative

value)

VBA2A

VBA4A

VBAT

VBA1

A

VBAT

927

ARJ

AR425

to 935

ARX

AMR

ARM

ARP

IRV

VEX

SRH

SRP

SRF

VCHR

ITV

ITVX

PVQ

VEF

VEP

VER

VEA

VY1

VBA

VBAT

AP100

VBA

VBAT

Tc Ts

Pressure

Stroke

Upper limit of pressure inside the tank P3

Inlet pressure P1

Time

Necessary supply

pressure to cylinder P

Sizing

( )

END

START

YES

YES YES YES

YES

When running continuously for longer periods of time, confirm the life expectancy.

When the life expectancy is shorter than required, select a larger sized booster regulator.

Select the tank

from table below.

Judgement of

flow rate

Extend

stop time Ts

up to charge time

T or more.

Avoid

pulsation.

(Max. 0.05

MPa)

Judgement

of charge time

T ≤ T s

Provide requisite

conditions for

selection.

Calculate required

air flow rate Q.

Select booster regulator

size from flow-rate

characteristics table.

Obtain the tank

capacity V.

Select the tank

capacity over V.

Calculate time T from

charge characteristics

table.

Increase number of

booster regulators (Z)

to decrease T.

Tank model

VBAT05

VBAT10

VBAT20

VBAT38

VBA1A

—

VBA2A

—

VBA4A

Applicable combination modelInternal capacity

5 L

10 L

20 L

38 L

•

Use the VBA11A (pressure increase ratio 4) with pressure

increase ratio 2 to 4. Usage of pressure increase ratio below 2

is preferred for the VBA10A (pressure increase ratio 2).

A stable operation and increased life expectancy will result.

•

Inlet supply pressure volume is {approximately twice (pressure

increase ratio 2), approx. 4 times (pressure increase ratio 4)}

the volume of the outlet side. Booster regulator requires the

inlet side volume which is the sum of the flow volume running

into the outlet side and the volume exhausted from E port (for

driving), because air is the power source.

Sizing can be achieved with the SMC Pneumatic System Energy Saving Program Ver. 3.1

which can be downloaded from the SMC website: http://www.smcworld.com

Caution

Lower limit of pressure inside the tank P2

100

200

0.5

0.8

Example

Necessary conditions:

D [mm]: Cylinder bore size

L [mm]: Cylinder stroke

W [mm/s]: Cylinder operating speed

C [pc.]: Number of cylinders

Tc [s]: Cylinder operating time

Ts [s]: Cylinder stop time

1 [MPa]: Inlet pressure

2 [MPa]

Note 1)

: Necessary supply

pressure to cylinder

Note 1) P2 is the necessary supply pressure to a cylinder, and set the pressure below the lower limit of pressure inside the tank

with a regulator. Adjust the pressure taking the maximum operating pressure of equipment in use into consideration.

Note 2) P

3 is the output pressure of the booster regulator, which is also the upper limit of charge pressure to the tank.

Other conditions:

Q [L/min (ANR)]: Required air flow rate

Qb [L/min (ANR)]: Outlet air flow rate of booster regulator

Tc [s]: Cylinder operating time

K: Cylinder double-acting: 2, single-acting: 1

3 [MPa]

Note 2)

: Tank charge pressure

1 [s]: Time to charge (Time to charge to P2)

2 [s]: Time to charge (Time to charge to P3)

[s]: Time to charge (Time to charge from P2 to P3)

Z: Number of booster regulators

Q [L/min (ANR)] =

π x D

x W

+ 0.101)

x 60 x C

4 x 10

0.101

Q =

π x 100

x 200 (0.8 + 0.101)

x 60 x 1 = 841 [L/min (ANR)]x

4 x 10

0.101

Refer to “Flow-rate Characteristics” on pages 926 and 927.

VBA2A: Qb = 600 [L/min (ANR)]

VBA4A: Qb = 1050 [L/min (ANR)]

NO: Need no tank

The VBA4A can supply necessary pressure.

The VBA2A cannot obtain necessary pressure.

3 – P2) x 9.9

V [L] =

(Q – Qb/2) x (Tc x K/60)

V = = 4.6 [L]

(1.0 – 0.8) x 9.9

Select the VBAT10, which can be

directly connected to the

VBA2A.

(841 – 600/2) x (0.5 x 2/60)

Refer to “Charge Characteristics” on pages 926 and 927.

T = ( ) x = 3.5 [s]

T [s] = ( ) x

2 – T1V

4.6

11.5 – 3.8

Series VBA

øD

P3P1

928

VBA22A, 42A

Air-operated type

Pilot pressure

IN (Inlet)

Governor

Booster

chamber A

Drive

chamber A

Switching valve

Piston

Drive chamber B

Booster chamber B

Check valve

OUT (Outlet)E

Piston rod

General line (low pressure) Locations requiring high pressure

Shortening time

Without check

valve by-pass

Time t (S)

Outlet pressure (MPa)

Operating pressure:

0.5 MPa

Bore size: ø100

Output ≈ 3850 N

Operating pressure:

0.8 MPa

Bore size: ø80

Output ≈ 4000 N

Equivalent

output

0.5 MPa

ø100

IN 0.5 MPa

ø80

OUT 0.8 MPa

VBA

Circuit Example

Working Principle

The IN air passes through the check valve to booster chambers A and B. Meanwhile, air is supplied to drive chamber B via the governor and

the switching valve. Then, the air pressure from drive chamber B and booster chamber A are applied to the piston, boosting the air in booster

chamber B. As the piston travels, the boosted air is pushed via the check valve to the OUT side. When the piston reaches to the end, the piston

causes the switching valve to switch, so that drive chamber B is in the exhaust state and drive chamber A is in the supply state respectively.

Then, the piston reverses its movement, this time, the pressures from booster chamber B and drive chamber A boosts the air in booster

chamber A and sends it to the OUT side. The process described above is repeated to continuously supply highly pressurized air from the IN to

the OUT side. The governor establishes the outlet pressure by handle operation and pressure adjustment in the drive chamber by feeding back

the outlet pressure.

VBA10A, 20A, 40A, 43A

Initially, inlet pressure (P1) passes through the check valve, fills P2,

and results in P1 = P2.

• When only some of the machines in the plant require high-pressure

air, booster regulators can be installed for only the equipment that

requires it. This allows the overall system to use low-pressure air

while accommodating machines requiring high-pressure air.

• When the actuator output is insufficient but space limitations prohibit

switching to a larger cylinder diameter, a booster regulator can be

used to increase the pressure. This makes it possible to boost the

output without replacing the actuator.

• When a certain level of output is required but the cylinder size must

be kept small so that the driver remains compact.

• When charging a tank or the like from a source at atmospheric

pressure, a circuit with a check valve can be used to reduce the

charge time by allowing air to pass through the check valve up to

the inlet pressure.

• When only one side of the cylinder is used for work, booster

regulators can be installed only on the lines that require them to

reduce the overall air consumption volume.

Booster Regulator Series VBA

(Two-stage

pressure boost)

VBA

Plant line (source pressure)

Piston rod

EOUT (Outlet)

Check valve

Booster

chamber B

Drive

chamber B

Piston

Switching valve

Drive

chamber A

Booster

chamber A

Governor

IN (Inlet)

VBA11A

929

ARJ

AR425

to 935

ARX

AMR

ARM

ARP

IRV

VEX

SRH

SRP

SRF

VCHR

ITV

ITVX

PVQ

VEF

VEP

VER

VEA

VY1

VBA

VBAT

AP100

VBA

VBAT