LENZE
2
Drive dimensioning
Gearbox designs
2-3
L-force gearboxes en 06/2011
Thermal power limit
The permissible gearbox permanent power is restricted by:
˘
The mechanical power, defined by the material strength
of the individual components or
˘
The thermal power limit, defined by the heat balance
The thermal power limit may be lower than the mechanical
power rating indicated in the selection tables.
The thermal power limit is determined by:
˘
The churning losses associated with the lubricant.
These are determined by the mounting position and
circumferential speed of the gears.
˘
The load and the speed
˘
The ambient conditions: temperature, air circulation,
heat input or dissipation via shafts and the foundation.
Drive size
Mounting positions A, B, E, F
Mounting positions C, D
ò
A …
ò
E
3000 rpm
3000 rpm
ò
F …
ò
G
3000 rpm
1500 rpm
ò
H …
ò
K
2000 rpm
1500 rpm
Please contact your Lenze sales office
˘
if the following input speeds n
1
are continuously exceeded
(more than 8h/day):
Drive size
Mounting positions A, B, E, F
Mounting positions C, D
ò
A …
ò
E
4000 rpm
3000 rpm
ò
F …
ò
G
4000 rpm
2000 rpm
ò
H …
ò
K
2000 rpm
1500 rpm
˘
if the following input speeds n
1
are briefly
exceeded:
Gearbox type
Gearbox size
Ratio i
Helical gearbox GST
07, 09, 11, 14
²
10
Shaft-mounted helical gearbox GFL
07, 09, 11, 14
²
16
Helical-bevel gearbox GKS
07, 09, 11, 14
²
25
˘
or if the following combinations of gearbox type, gearbox
size and ratio occur with an input speed of n
1
> 1500 rpm
Possible ways of extending the power range:
˘
Synthetic lubricant (option)
˘
Shaft sealing rings made from FP material/Viton (option)
˘
Reducing the amount of lubricant
˘
Cooling the geared motor by air convection on the
machine/system