OPTIMUM
M A S C H I N E N - G E R M A N Y
Operation
Version 1.0 dated 2015-05-27
Page 61
Original operating instructions
F3
GB
For the following working steps, please proceed as described in „Operation and
programming“ of the Siemens "SINUMERIK 808D" Operation instructions.
6.9
Central lubrication system
The CNC machine is equipped with a central lubrication system.
The lubricating system is used to maintain an oil film on the slideways, the bearings, the ledges
and the ball screws and to reduce their wear.
In case of a failure or a fault in the central lubricating system, a stick-slip effect may occur. This
effect describes the jerky sliding of solid bodies moving opposite one another. For instance:
creaking doors and rattling windscreen wipers.
6.10
Data interfaces and current collection
When connecting data interfaces make sure that the data cable runs to the control unit interface
via the shortest possible distance. The cable routing can be conducted along the measuring
system lines. However the cable in the switch cabinet must never be routed near the drive units
of the NC axis or the frequency converter itself. Electromagnetic radiation causes errors during
data transfer (EMC problems).
The control is equipped with the following data interfaces.
X130 Ethernet port (RJ45 connector, only 808D ADVANCED)
USB connection
Connection for power supply
6.11
Selecting the speed
The correct speed is an important factor for milling. The speed determines the cutting speed by
which the cutting edges cut the material. By selecting the correct cutting speed, the service life
of the tool is increased and the working result is optimized.
The optimum cutting speed mainly depends on the material and on the material of the tool. With
tools (milling cutters) made of hard metal or ceramic insert it is possible to work with higher
speeds than with tools made of high-alloy high speed steel (HSS). You will achieve the correct
cutting speed by selecting the correct speed.
In order to determine the correct cutting speed for your tool and for the material to be cut you
may refer to the following standard values or a table reference book (e.g. Tabellenbuch Metall,
Europa Lehrmittel, ISBN 3808517220).
The required speed is calculated as follows:
n = speed in min
-1
(revolutions per minute)
V = cutting speed in m/min (meter per minute)
d = tool diameter in m (Meter)
6.11.1 Standard values for cutting speeds
[ m/min ] with high-speed steel and hard metal in upcut milling.
n
V
d
------------
=
Tool
Steel
Grey cast iron
Al
alloy
age-hardened
Plain mill and side milling cutters [ m/min
]
10 - 25
10 - 22
150 - 350
Relieved form cutters [ m/min ]
15 - 24
10 - 20
150 - 250
