Relief Valves (High Pressure Type)
Relief valves here have been particularly developed those be able to adjust pressure to highlevel of 35 MPa. Able to protect pumps and control valves against excessive pressures,
they are used to control the pressure in the hydraulic system to a constant level.
Remote control and unloading are permitted by using vent circuits.

■ Specifications
Model Numbers

Max. OperatingPres.
MPa

Pres. Adj. Range
MPa35★ - 35

B3G−03−＊−10
B3G−06−＊−10

Max. Flow
L/minApprox. Masskg

250

4.1

500

5.1

★ See minimum adjustment pressure characteristics on page C-15.

■ Model Number Designation
B3

G

Series Number

Type ofMounting

B3：Relief Valves(High Pressure Type)

Ｇ：Sub-plate
Mounting−03−V−10

Valve SizeHigh Venting★
Pres. Feature

DesignNumber

Ｖ：For High Venting
Pressure Feature(Omit if not required)

1003
06

Graphic Symbols

10★U se the high venting pressure type where it is necessary to reduce the changeover time fromunloading to onloading.

Vent Connection■ Accessories■ Sub-plates● Mounting Bolts
Valve ModelNumbers
B3G−03

Socket Head Cap Screw
M12×40L …… 4 Pcs.

B3G−06

M16×50L …… 4 Pcs.

Valve ModelNumbers
B3G−03B3G−06■ Instructions● When control in the vent circuit, if the internal volume of the vent line
is too large, chattering is likely to occur. Thus, as far as possible reducethe inside diameter and the length of the pipe.
● To adjust the pressure, loosen the lock nut and turn the handle slowly
clockwise for higher pressures or anti-clockwise for lower pressures.
After adjustments, do not forget to tighten the lock nut.
● Piping of the tank line should not be connected to any tank line of theother valves, but connected directly to the reservoir.
● With a small flow, the setting pressure may be unstable. Use with theminimum flow rate as the below chart.
Valve Size
0306

C-14

Sub-plateModel Numbers
BGM−03−20

BGM−03X−20
BGM−06−20
BGM−06X−20

Thread Size
Rc
3／
81／
2
3／
41Approx.
Mass kg
2.4
3.1
4.7
5.7

● Sub-plates are available. Specify the sub-plate model number
from the table above. When sub-plates are not used, the mounting
surface should have a good machined finish. (1.6 )● T he sub-plates are those for pilot operated relief valves. For
dimensions, see page C-9.

Min. Flow
5 L/min

Relief Valves (High Pressure Type)PRESSURE CONTROLSMounting Surface
B3G−03：ISO 6264−06−09−1−97
B3G−06：ISO 6264−08−13−1−97

B3G−0306−＊−10★P ressure is limited by collars fitted. If
a working pressure cannot be attained,
remove some collars. One collar is"K" Dia. Throughequivalent to 14 MPa.
"N" Dia. Spotface

Fully Extended 167.5
Fully ExtendedFCVent Port
Two Collars★

INC.

Lock Nut
14 Hex.

100

Pressure Gauge ConnectionRc 1/4 Thd.

13T

77

44 Dia.

Pressure Adjustment
Handle52

B3G−03B3G−06

Mounting Surface(O-Rings Furnished)

6Locating Pin
6 Dia.

Model Numbers

ＡＢ

Ｃ

Ｄ76

53.8

11.1

26.9

100

70

15

35

Ｅ
53.8

66.7

VHUＦ

Ｈ

74.6

Ｋ

29.3

63.8

43.7

13.5

17.5

Note: For dimensions of the valve
mounting surface, see thedimensional drawing (Page C-9)of the sub-plate used together.

ＮＴ

2121.527

Ｕ

B3G-03

111

26

Pressure

Pressure

50

100

150200250

0100

200300400

Vent Pressure
Min. Adjustment Pressure

Specific Gravity : 0.850

B3G-030.6
Low Vent Pressure Type
50100High Vent
Pressure Type

1.2Pressure

Pressure

B3G-06

High Vent
Pressure Type0.4
MPa 0.2
150500Flow Rate L/min■ Min. Adj. Pressure and Vent Pressure vs. Flow Hydraulic Fluid: Viscosity : 35 mm²/s

022.3

B3G-06

Flow Rate L/min

0.8

31.2

1253534332524231514
MPa 135433534332524231514
MPa 135431

ＶHydraulic Fluid: Viscosity : 35 mm²/s
Specific Gravity : 0.850■ Nominal Override Characteristics

0High Pressure TypeTank PortAB

DC4 Places

Pressure Port

E200

Flow Rate L/min

250

10.80.6

MPa 0.40.2

Low Vent Pressure Type
0100

200

300

400

Flow Rate L/min

500

Note: Vent Pressure means the relief pressure when the vent part open to the tank line.

Relief Valves (High Pressure Type)

C-15

■ List of Seals
B3G−03, 06
30

7

8

2

16

33

9

17

10

12

14

15

13

19
11
24
25

C-16

22

21

26

323

431

520

6

18

1Item

Name of Parts

17
18
19
20
21
22
23
24
25
26

O-RingO-RingO-RingO-RingO-RingO-RingO-RingO-Ring
Back-up Ring
Back-up Ring

Part Numbers
B3G-03
B3G-06OR NBR-70-1 P9-N
OR NBR-70-1 P9-N
OR NBR-90 P18-N
OR NBR-90 P28-N
OR NBR-90 P14-N
OR NBR-90 P14-N
OR NBR-90 P9-N
OR NBR-90 P11-N
AS568-123（NBR-90）
AS568-123（NBR-90）
AS568-025（NBR-90）
AS568-025（NBR-90）
AS568-024（NBR-90）
AS568-024（NBR-90）
AS568-012（NBR-90）
AS568-012（NBR-90）
SO-BRB-34
SO-BRB-34
SO-BRB-32
SO-BRB-32

Relief Valves (High Pressure Type)

Qty.
12
1
111
1
2
11