Flow Direction; Shaft Seal - Bosch Rexroth A6VM series 71 Manual

6 A6VM series 71 | Axial piston variable motor

Flow direction

Filtration of the hydraulic fluid
Finer filtration improves the cleanliness level of the hydrau-
lic fluid, which increases the service life of the axial piston
unit.
A cleanliness level of at least 20/18/15 is to be maintained
according to ISO 4406.
At very high hydraulic fluid temperatures (195 °F (90 °C) to
maximum 217 °F (103 °C), measured at port T), a cleanli-
ness level of at least 19/17/14 according to ISO 4406 is
necessary.
Influence of case pressure on beginning of control
An increase in case pressure affects the beginning of con-
trol when using the following control options:
▶ HP, HA.T3: Increase
▶ DA: Decrease
With the following settings, an increase in case pressure
will have no effect on the beginning of control:
HA.R and HA.U, EP, HA
The factory setting of the beginning of control is made at
p = 30 psi (2 bar) case pressure.
abs
Flow direction
Direction of rotation, viewed on drive shaft
clockwise (cw)
A to B
Bosch Rexroth Corp., RE-A 91610/12.2015
counter-clockwise (ccw)
B to A

Shaft seal

Permissible pressure loading
The service life of the shaft seal will be influenced by the
speed of the axial piston unit and the leakage pressure in
the housing (case pressure). Momentary pressure spikes
(t < 0.1 s) of up to 145 psi (10 bar) are permitted. The
service life of the shaft seal decreases with increasing
frequency of pressure spikes and increasing mean differen-
tial pressure.
The case pressure must be equal to or higher than the
ambient pressure.
Rotational speed n [rpm]
2000 4000
75 (5)
NG85
60 (4)
45 (3)
NG115, 150
30 (2)
NG170, 215
15 (1)
0
NG215
The FKM shaft seal may be used for leakage temperatures
from -13 °F to +240 °F (-25 °C to +115 °C). For application
cases below -13 °F (-25 °C), an NBR shaft seal is required
(permissible temperature range:
-40 °F to +195 °F (-40 °C to +90 °C)).
6000 8000 10000
NG60
NG60
NG85
NG150 NG115
NG170