Welcome to "SINUMERIK Live - application technology simply explained" - our video series that
presents SINUMERIK topics in a realistic way and will take up just a few minutes of your time.
Today, we look at: Turn-milling using a counterspindle, multi-channel technology, and balance cutting:
Our agenda for today: Counterspindle machining.
Why do I need a counterspindle on a turning machine?
Next, what is multichannel machining and how does it work?
And again, the practical demonstration on our EMCO HyperTurn 65.
Continuing from our last video on turn-milling with a CY axis, we will today turn our attention
to the B axis and multi-spindle technology.
Let's start with some basic facts about counterspindles: The counterspindle is positioned directly
opposite the main spindle.
The counterspindle is a full-fledged extension of the main spindle, two machines rolled into
one, so to speak.
It is programmed in SINUMERIK Operate in just the same way as the main spindle, and the
control translates the geometry and the machining sequences and order automatically to the counterspindle.
The function and handling of the counterspindle can be divided into four basic functions.
These are workpiece transfer, then support/stabilization, and positioning and fixing.
In practice, this means that the part is clamped in the main spindle and the counterspindle
grips the part and takes it over.
That is, it is transferred from the main spindle to the counterspindle, making it possible
to execute different types of machining, for example, machining on the rear of the part,
for instance, to face-turn the rear of the workpiece, or drill into it, and so forth.
Our second point is support/stabilization, which is an important aspect if a part is
of a certain length and produces unbalance or vibration; in this case, a counterspindle
can provide support making it easier to machine the part.
The third point is positioning.
The main spindle grips the part, the counterspindle takes it over and moves it into a defined
position where machining continues.
And the third point is fixing, which means that the semi-finished part or workpiece,
which is clamped in the main spindle, is removed or parted off.
The counterspindle then grips the parted-off section and machining can continue with the
knowledge that the removed piece will not become a projectile.
Whether a counterspindle will be used is specified in SINUMERIK Operate at the beginning of the
program.
If it is, the precise function that the counterspindle will perform is selected in the intelligent
counterspindle cycle from the four functions that we have already mentioned.
After this has been programmed, a realistic machining process can first be simulated and
displayed in the simulation.
General features of multi-channel technology.
The number of channels of a machine tool is based on the number of tool carriers, so if
a machine has more than one tool carrier - two, three, or four - we talk about a multi-channel
machine.
For each additional tool carrier, another channel has to be provided.
At the start of the NC program that we are writing, we specify whether this is going
to be single-channel or a multi-channel program.
If it is to be a multi-channel program, we then define which channel will be the leading
channel and which channel will be the following channel.
It is very important to remember to set and position WAIT markers - these are wait or
synchronization points that prevent moving tool carriers from colliding.
An important function in multi-channel technology is balance cutting.
This means that two tool carriers work on the same machining profile at the same time.
This helps on the one hand to balance out the cutting forces, because the two tools,
that is their cutting forces, cancel each other out.
And on the other hand, it also helps to increase the volume of material removed.
They are two strategies for doing that: synchronous path control of tools and asynchronous path
control of tools, which is also called offset path control.
Synchronous path control of tools is usually used to increase the feedrate, in fact, to
double the feedrate.
Tool offset path control is usually used to double the infeed.
In this case, each tool is working on the same machining profile but to different infeed
depths.
In order to machine our example workpiece, in this case, using an HSK-type toolholder
- that is, HSK taper size 100 - we will use a turn-milling machine with the following
kinematic constellation.
Channel 1 is a milling spindle, the so-called B axis.
It rotates about Y and can be positioned and set at any angle to the workpiece.
It is of no consequence whether it is on the main spindle or counterspindle, both are possible.
Channel 2 is a tool carrier, a tool turret that is located below the workpiece.
This is channel 2.
The B axis, the milling spindle, channel 1, which rotates around Y, can hold turning,
drilling, or milling tools on its spindle.
We will machine the example workpiece, the HSK 100, on a two-channel turn-milling machine.
Channel 1 is our milling spindle, the B axis at the top.
Channel 2 is the conventional turret below it, and on the left we can see the main spindle
with our blank.
This will be machined first.
On the right, we can see the counterspindle, which will take over the semi-finished or
incomplete part toward the end of the program, in order to pass it on to finish machining.
And in the same way that the channels physically exist on the machine, they also, of course,
exist in the control.
Channel 1 on the left is our B axis.
Channel 2, our turret, is on the right.
Here they are again, this time in different colors.
You can also see that they are two entirely different programs, executed independently
of each other but synchronized with the WAIT markers, which we have already talked about,
to prevent collisions between the tool carriers.
And the program is executed only after the simulation has been performed, which checks
the whole process realistically.
What happens during the production process?
Here we see a realistic representation in three dimensions, showing both spindles, the
main spindle and the counterspindle, and here is a half-section, which is particularly important
for internal machining.
This is like looking inside the workpiece.
We can also show a side view in volume module format, and a front view of both spindles.
And back again to the three-dimensional view.
After we have carefully checked the simulation, we can start actual machining on the machine tool.
In our video today, we discussed two topics: Counterspindle machining and multi-channel
technology.
Of course, the user initially sees himself faced with increased procurement and maintenance
costs for machines and tools, and the training requirement for the operators is greater.
But: The advantages for the user outweigh significantly:
There are great time savings to be made by the reduction in setup times, machine downtimes,
and throughput times.
And by extension that means shorter delivery times and a flexible machine park.
That's all for today, thanks for watching and see you next time.