SKF VP Series User Manual

- 36 -
951-180-083-EN
Version 01
EN
3. Overview, functional description
3.5.1 Functioning of a VPK progressive metering device
The task of the progressive metering device
is to consecutively distribute specified por-
tions of the pressure-fed lubricant (grease
or oil) to the connected lubrication points.
The lubricant continues to discharge as
long as it is pressure-fed to the progressive
metering device. The specified portions are
generated through the piston movement.
Two lubricant outlets on the two end posi-
tions of the piston travel are allocated to
each piston.
The number of pistons within a metering
device is variable from 3-10. If lubricant
is pressure-fed, the pistons of a metering
device move sequentially to their end posi-
tion. The piston movement displaces the
lubricant upstream of the piston towards the
downstream outlet. The piston movement
can only start if the upstream piston has
reached its end position. If all pistons are in
their left or right end position, internal con-
necting bores in the metering device ensure
that the pistons continue running reliably as
defined.
If all pistons have moved once to the left
end position as well as to the right end posi-
tion, all connected lubrication points have
been supplied once with the preset lubricant
quantity.
The portions for both outlets are deter-
mined by the diameter and the distance
traveled by the piston.
The selection of the required portion is
made during the design of the metering
device. A subsequent change of the portions
is only possible through modification of the
metering device / replacement of the meter-
ing device section.
Information on the design
The general criteria for the design of pro-
gressive metering devices also apply without
restrictions to the sectional progressive
metering devices. The most important crite-
rion is the number of cycles (stroke rate). It
should be kept as low as possible by select-
ing sections with a sufficiently high volume.
A maximum value of 200 cycles/min should
not be exceeded.
This also reduces pressure losses and noise
levels. In case of an installation on moving
machine parts or in case of strong vibra-
tions (e.g. on pressing machines), the piston
position of the metering device should not
correspond with the direction of movement
of the machine part.

SKF VP Series Specifications

General

Brand	SKF
Model	VP Series
Category	Industrial Equipment
Language	English