Bosch Rexroth A2FM series Instruction Manual page 4

4 A2FM for explosive areas | Axial piston fixed motor
Hydraulic fluids
Viscosity and temperature of hydraulic fluids
Cold start
Permissible temperature difference
Warm‑up phase
Continuous operation
Temperature class T3
Temperature class T4
Short‑term operation
▼ Selection diagram
Maximum permissible viscosity for cold start
Optimum operating viscosity range v
Optimum efficiency
Minimum permissible viscosity for short‑term operation
Minimum permissible temperature for cold start
Filtration of the hydraulic fluid
Finer filtration improves the cleanliness level of the hydraulic
fluid, which increases the service life of the axial piston unit.
A cleanliness level of at least 19/17/14 is to be maintained
according to ISO 4406.
Bosch Rexroth AG, RE 91001-01-X-B2/01.2016
Viscosity Temperature
ν ≤ 1600 mm 2 /s θ
max St
ΔT ≤ 25 K
ν < 1600 to 400 mm 2 /s θ = −40 °C to −25 °C
ν = 400 to 10 mm /s
2
θ = −25 °C to +90 °C
θ = −25 °C to +70 °C
ν = 36 to 16 mm 2 /s
opt
ν ≥ 7 mm 2 /s
min
1600
1000
600
400
200
100
60
40
36
20
16
opt
10
7
-40
Comment
≥ −40 °C t ≤ 3 min, n ≤ 1000 rpm, without load p ≤ 50 bar
between axial piston unit and hydraulic fluid in the system
at p ≤ 0.7 × p
this corresponds, for VG 46 for example, to a temperature
range of +5 °C to +85 °C (see selection diagram)
measured at port T
observe permissible temperature range of the shaft seal
ring (ΔT = approx. 12 K between bearing/shaft seal and
port T)
Range of optimum operating viscosity and efficiency
t < 3 min, p < 0.3 × p
Warm‑up phase
-25 -10 0 10
Temperature θ [°C]
, n ≤ 0.5 × n and t ≤ 15 min
nom nom
nom
30 50 70 90 115