22
Table 6
Order form for a flow limiter assembly (for examples of type identification codes, see Chapter
3.1 "Type identification code
of flow limiters of series SMBM"
)
Module
Component
designation
Type
Design
(X/V/N)
Monitoring
(../N)
Electrical connection
(XX/CA/CS/XA/XS/N)
Code
(D
1
/D
1
+D
2
/N)
ATEX design (-
EEX/N)
1 or dummy module N
SMB
M -
2 or dummy module N
SMB
M -
3 or dummy module N
SMB
M -
4 or dummy module N
SMB
M -
5 or dummy module N
SMB
M -
6 or dummy module N
SMB
M -
Inlet and outlet threads
BSPP
..........
...........
Attachments
Changeover valve (only SMBM-V) Yes/No
Filter unit with ball valve Yes/No
NOTE
When using dummy modules, the letter "N" must be used to mark all order specifications within the respective order code. Example:
SMBM-NNNNNNN
IMPORTANT NOTE
Avoiding malfunctions
It is not permitted to use a mixture of SMBM-X and SMBM-V on a single base plate, because otherwise
the flow limiter SMBM-X will not be supplied with oil during the valve setting for start-up operation!
3.5 Application
Flow limiters are used in circulating-oil lubrication systems.
They supply the lubrication points of the connected system with
the required oil quantities. These individual oil quantities are
independent of fluctuations of operating pressure and, in wide
ranges, are also independent of oil viscosity. This makes them
the ideal solution for applications with fluctuating oil
temperatures, such as may occur, for example, in steel mills or
in mining operations. Their self-regulating operating principle
makes elaborate pressure regulation unnecessary.
The flow limiter series SMBM is designed for setup on base
plates in assemblies of 1 to 6 flow limiter modules. The use of
plug-in nozzles makes it possible to set the oil quantity in
increments from 0.08 to 8 l/min. (0.17 to 16.9 pts/min).
One pump supplies the main pressure line with oil. The flow
limiters directly connected to this main line divide up the total oil
quantity into smaller, constant oil quantities. The option exists
of installing progressive metering devices or flow dividers
downstream of the flow limiters in order to divide up the oil
quantity even further into ever-smaller partial flows.
The function can be monitored by signal transmitters or gear
wheel-type flow indicators which are mounted on the flow
limiters and connected to a monitoring unit.
3.6 Functional description
See Figure
6
and Figure
7
The SMBM flow limiters are individual modules for setup on
base plates. Functionality for the two series (SMBM-X and
SMBM-V) is identical.
The total volumetric flow
Q
in
,
which is supplied to a flow limiter
assembly, is divided up into individual volume flows
Q
out
by the
flow limiter modules. For this, the system pressure, designated
as inlet pressure
p
1
in the presentation, is identical for all flow
limiters on the same base plate.
Every flow limiter has a spring-loaded control piston
SK
with
a plug-in nozzle
D
1
(SMBM-X) or two plug-in nozzles
D
1
/ D
2
(SMBM-V), which act as differential-pressure valves.
The nonadjustable restrictor
D
1
is available in different nozzle
sizes (see table 3: Plug-in nozzle table SMBM-X D
1
). The plug-
in nozzles which act as nonadjustable restrictors (
D
1
or
D
1
/
D
2
,
see table 4: The plug-in nozzle table for SMBM-V with D
1
and
D
2
) in the control piston determine the flow rate (Fig. 7), while
D
3
represents a variable restrictor which is formed by the outlet
boreholes arranged in a circle in the throttle bushing and by the
lower edge of the control piston which partly covers over these
boreholes.
