1
HA 5221
7/2008
M20 x 1,5 • p
max
350 bar • Q 30 L/min
Pilot Operated Check Valves
Pilot to Close
SCC5H-Q3/l
q
Load-holding without leakage
q
Low pressure drop
q
Pilot seal
q
Fits the same cavity as the Q3 overcentre valve
1
2
3
Replaces
HA 5221 9/2006
Functional Description
The one-way control valves make the flow possible in
one direction with a low pressure drop and prevent from
the flow in opposite direction.
The pressure in channel (1) causes a lifting of the valve
ball from the seat against the spring. In this way
it is released the flow from (1) into (2). The flow in the
direction from (2) to (1) is not possible because the
spring action and pressure in channel (2) result
in pressure exerted to the valve ball in the seat.
The control pressure in channel (3) acts to the control
gate valve pressing the valve ball in the appropriate valve
seat. In this way the flow is shut off closely in both the
directions.
Control pressure
for shutting off the valve =
At computing the control pressure it is necessary to take
into consideration that the pressure in channel (2)
increases the necessary control pressure by the same
value multiplied by an efficient differential area having a
value of 1-1/2 at a ratio of control areas of 2:1.
As for basic surface treatment the external part of the
valve are zinc coated.
Pressure of channel (1)
2
2
HA 5221
0 1020304050
10
5
15
20
25
Pressure p barD []
FREE FLOW
Flow Q L/min[]
Flow Q US GPM[]
Pressure p PSID []
0 2.5 5.0 7.5 10 12.5
100
50
150
200
350
250
300
Ordering Code
SCC5H-Q3/l
Pilot Operated Check Valve
Pilot to close
Technical Data
Cavity M20 x 1.5
Maximum flow L/min 30
Max. pressure bar 350
Pilot ratio 2:1
Pressure drops bar see Dp - Q characteristics
Hydraulic fluid Hydraulic oil (HM, HV) according to DIN 51524
Fluid temperature range °C -20 ... +90
Viscosity mm
2
/s 20 ... 400
Maximum degree of fluid contamination According to ISO 4406, Class 21/18/15
Weight kg 0.08
Maximum valve tightening torque
in valve body or in control block
Nm 45
+2
Mounting position Unrestricted
Dp-Q Characteristics Measured at n = 40 mm
2
/s
Pilot ratio
Standard 2:1
2
Seals
no designation NBR
3
HA 5221
6HR24
M20 x 1,5 -6g
3
2
1
HEX 24.0
M20 x 1.5-6g
Cavity Measurements in millimeters
Dimensions Measurements in millimeters
A
Æ
Æ
Æ
16.05
16.00
Æ 15.00 MAX
17.55
17.50
M20x1.5-6H
21.90
21.80
Æ 30
15°
13.5
2.80
2.40
30.0
11.0
43.0
45°
13.5
30.0
40.0
Æ
8.0
MAX
Æ
4.0
1.6
0.08
1.6
0.3
1.6
1.6
Æ 0.05
-A-
Æ 0.08
B
A
B
Æ 0.08
30°
30°
A
4
HA 5221
Caution!
The packing foil is recyclable.
The technical information regarding the product presented in this catalogue is for descriptive purposes only. It should
not be construed in any case as a guaranteed representation of the product properties in the sense of the law.
ISO A
Valve Bodies Measurements in millimeters
Seal kits on request.
Spare Parts
The use of aluminium bodies is limited to a maximum operating pressure of 210 bar.
Subject to alteration without notice!
ARGO-HYTOS s.r.o. CZ - 543 15 Vrchlabí
Tel.: +420-499-403 111
E-mail: info.cz@argo-hytos.com
www.argo-hytos.com
2x OTVOR2x OTVOR2x OTVOR
2x HOLES Æ 9.0 THRO¢
Body without valve
Material Ports Port size Type code
Aluminium
1, 2 G3/8
SB-Q3-0103AL
3 G1/4
1, 2 SAE 8, 3/4-16
SB-Q3-0104AL
3 SAE 6, 9/16-18
Steel
1, 2 G3/8
SB-Q3-0103ST
3 G1/4
1, 2 SAE 8, 3/4-16
SB-Q3-0104ST
3 SAE 6, 9/16-18
