OVERLOAD
PROTECTOR
1. Introduction：
Overload protector is installed on press in order to check the overload hydraulic
pressure of cylinder inside the slide. The hydraulic pressure of cylinder will be
released immediately within 3/1000 seconds when overload occurs. And press will
stop working urgently as soon as receiving the signal from limit switch, in order to
protect the die and press.
After overload occurred, will quickly compensate oil of cylinder to reach normal
working pressure by air driven hydraulic pump, in order to operate the press normally.
Furthermore, overload protector to have pressure control valve, which can prevent
effects of excessive rising of hydraulic pressure caused by raised temperature when
press is operating.
2. Selection of Model： V A 0 8
-
□
1
□
2
□
3
(
Suitable for press
200 tons
& down
)
Setting range of
overload hydraulic
pressure
(Kgf/cm
2
)
Type of limit switch
Volume of oil tank
(Liter)
5：x 50 times
7：x 70 times
9：x 90 times
2 : NO type
6 : NC type
0： None
1： 1.2
3： 4.0
5： 8.0
3.
Specification
：
2005.07.08
SANDSUN
1
Model
VA08-5□0
VA08-7□0
VA08-9□0
Releasing flow rate
cm
3
/sec
15500
13000
11500
Area of orifice
cm
2
0.7
0.5
0.4
Method of setting pressure
Air pressure
x 50 times
Air pressure
x 70 times
Air pressure
x 90 times
Range of setting pressure
kgf/cm
2
150
~
250
210
~
350
270
~
450
Air supply
kgf/cm
2
3
~
5
Capacity of press
200 ton
& down
Air consumption
N
l
/min
220
Maxi. noise
dB
77
Discharging pressure of pump
kgf/cm
2
Air pressure x 22 times
Hydraulic oil
ISO-VG-32 or equivalent