Roemheld 2951-416 User manual

Römheld GmbH · Postfach 12 53 · D-35317 Laubach · Phone + 49 (0) 64 05 / 89-0 · Fax [phone] / 89-211 · www.roemheld.com
Page 1/2
Fitters and setters of machine tools. They
have to be familiar with the handling and
mounting of hydraulic components.
Locking of leakage-free hydraulic
cylinders, i. e. for maintaining the
pressure and/or the position, can also be
used in combination with non-leakage
free directional control valves.
Pilot-operated check valves are not
suitableforlockingofdouble-actingswing
clamps (pull-type cylinders). Due to the
unfavourable surface ratio of these
elements, the control pressure is not
sufficient for unlocking and dangerous
pressure intensifications occur. For such
applications use type 2951-421.
!Swarf or contamination in the hydraulic
oil lead to increased wear or damage at
the guides, running surfaces and seals.
!The maximum operating pressure and
the admissible flow rate of the valve
must not be exceeded.
!Use hydraulic oil as per Roemheld data
sheet A 0.100.
Check valves are spring-loaded ball-type
poppet valves (leakage free).
The flow B →A is free. The flow from A →
B is locked, but it can be hydraulically
unlocked by pressurising control port Z.
Operating Instructions
Check Valves, Pilot Operated
These operating instructions are
available for pilot-operated check
valves of the following types:
2951-416
2951-417
2951-421
2951-501
Target group of this
document
Provided use
Safety
Troubles of functioning
Protect against swarf, otherwise
check valves might not seal.
Instructions for safe
operation
Function
BA_D8755
Issue 03/2004

BA_D8755
Issue 03/2004
Subject to changes without notice.
Page 2/2
Any mounting position of the check valves
is possible.
!Return the leakage return port L
depressurised at the reservoir.
Type 2951-416 (for manifold-mounting)
!Drill holes for hydraulic oil supply and
return in the fixture.
!Grind flange surface.
!Clean the support surfaces.
!Fasten the valve with O-rings on the
fixture.
Provide the threads in the fixture.
!Connect hydraulic lines to qualifying
standards, pay attention to scrupulous
cleanness! See also Römheld data
sheets A0.100, F9.300, F9.310 and
F9.360.
!Use only fittings "screwed plug B" as
per DIN 3852 (ISO 1179).
!Do not use sealing tape, copper rings or
coned fittings.
!Check sealing of the hydraulic
connections!
Check if the hydraulic ports are tight
(visual control). The valve itself is
maintenance free.
100
200
0
100 200 300 400 500
0
2951-501
2951-417
2951-421
0
2
4
6
8
10
1002030405060
2951-417
2951-501
All figures are schematic figures.
1 2
Control pressure pZfor unlocking at
(pB= 0 bar)
∆p-Q-curves only valid for flow
from B →A and for unlocked return
line A →B
Flow resistance ∆p[bar]
Flow rate Q [l/min]
Control pressure pZ[bar]
pA[bar]
Installation Hydraulic connection
General characteristics
Part-no. 2951-416 2951-417 2951-421 2951-501
Port A, B Ø 5 G1/4 G1/2 G1/2
Control port Z Ø 3.5 G1/4 G1/4 G1/4
Control pressure pZ≥bar 0.3 pA+ 12 0.32 pA+ 12 0.12 pA+7 0.38 pA+ 12
Max. operating pressure bar 500 500 500 500
Max. flow rate l/min 20 15 55 55
Maintenance
Data sheets
Types Corresponding data sheets
2951-417,
2951-501 C2.9511
2951-416 C2.9512
2951-421 D8.755

Römheld GmbH · Postfach 12 53 · D-35317 Laubach · Phone + 49 (0) 64 05 / 89-0 · Fax [phone] / 89-211 · www.roemheld.com
Page 1/2
Fitters and setters of machine tools. They
have to be familiar with the handling of
hydraulic components.
The hydraulic intensifer has been
designed for the use in clamping fixtures
to increase the hydraulic pressure.
Pressure intensification is effected in
intensification ratio i.
!Swarf or contamination in the hydraulic
oil lead to damage of the intensifier.
!Insert filter 10µ for continuous
functioning.
!Use hydraulic oil as per data sheet
A0.100.
!If the intensifier will be used on
uncoupled systems (no connection to
the pressure generator), a pilot-
controlled check valve should be
mounted at the high-pressure side to
guarantee a safe holding of the load
(data sheet C 2.9511).
The hydraulic intensifer increases the
pressure at the input side to a higher
pressure in the indicated intensification
ratio i (see chart page 2).
The intensifer allows a high flow rate at
low pressure and switches automatically
to pressure intensification in case of
increasing counter pressure.
!Hydraulic connection.
!For pressure built-up line Rto the
reservoir has to be discharged.
!Pressurise port IN (pressure will be built
up in line H).
!Pressure intensification will be
automatically activated.
!To retract the cylinder line Rhas to be
pressurised and line IN to the reservoir
discharged.
!Connect hydraulic lines to qualifying
standards, pay attention to scrupulous
cleanness! See also Roemheld data
sheets A0.100, F9.300, F9.310 and
F9.360.
!Use only fittings "screwed plug B" as
per DIN 3852 (ISO 1179).
!Do not use sealing tape, copper rings or
coned fittings.
!Check sealing of the hydraulic
connections!
!Connection at mounting thread (1) (see
drawing page 2).
!The hydraulic intensifier can be directly
screwed into the fixture.
Operating Instructions
Hydraulic Intensifier
Hydraulic Intensifier
"continuously acting
"with hydraulic port and tubes or
with hydraulic manifold mounting
port and plug-type connectors
These operating instructions are
available for the following types:
8755-015 8755-132
8755-020 8755-140
8755-032 8755-148
8755-040 8755-162
8755-050 8755-175
Target group of this
document
Provided use
Material damage
With hydraulic pressure very high
forces are generated. The fixture
or machine must be in the position
to compensate these forces.
Instructions for safe
operation
Material damage
Do not exceed maximum operating
pressure and maximum flow rate!
Pressure spikes have to be
avoided.
Function
Troubles of functioning
During operation there is a leakage;
therefore use in cycling mode is not
possible.
Instructions for operation
Hydraulic connection
BA_D8755
Issue 03/2004

BA_D8755
Issue 03/2004
Subject to changes without notice.
Page 2/2
B
.
Bleed the hydraulic lines during start-up of
the system, otherwise clamping times can
be considerably prolonged and function
problems can be caused.
The filters in the hydraulic system have to
be cleaned regularly and exchanged in
case of strong contamination. Check if the
hydraulic ports are tight (visual control).
The hydraulic intensifier itself is
maintenance free.
1
HR
IN
Installation of the hydraulic intensifier
Hydraulic bleeding Maintenance Port Function
IN Input (clamping)
RDischarge line (unclamping)
HHigh-pressure output
Intensification
Type Intensification i Max. flow rate low-pressure
side QIN [l/min] Max. flow rate high- pressure side QH[l/min] Max. operating pressure low- pressure side PIN in [bar] Max. operating pressure high- pressure side PHin [bar]
8755-015 1,5 81,0 200 300
8755-020 2,0 80,8 200 400
8755-032 3,2 15 2,5 155 500
8755-040 4,0 14 2,0 125 500
8755-050 5,0 14 1,6 100 500
8755-132 3,3 80,5 151 500
8755-140 4,0 80,4 125 500
8755-148 4,8 80,4 104 500
8755-162 6,2 80,3 80 500
8755-175 7,5 80,3 66 500
Accessory: pilot-operated
check valve
Accessory: Filter unit
Trouble shooting
Trouble Cause / Remedy
System reduces pressure Check valve is leaky
- Exchange hydraulic intensifier or external check valve
No pressure built-up
pressure in R line not reduced
- Reduce pressure in R line
Filter contaminated
- Exchange filter
Data sheets
Types Corresponding data sheets
8755-015
8755-020
8755-032
8755-040
8755-050
8755-132
8755-140
8755-148
8755-162
8755-175
D8.755
All figures are schematic figures.