Cnc Automatic Lathes Or Cnc Multi Spindle Lathes
Managers of precision machining companies have usually this dilemma: What is more convenient for my company, standard CNC automatic lathes or Multi Spindle machines?
Everyone thinks of competitivenes to win competitors, as well the best productivity and reliability for their parts. For this, investors compare tool cost, cycle times, energy savings, coolant costs, set up times, floor space, etc.
Next to this, you'll find a comparison of the cost structure of the investment. We analyze each cost one by one comprared between cnc automatic lathes and cnc multi spindle lathes:
1) PRODUCTIVITY: Everyone who heard about multispindle machines knows that those are from 5 to 6 times more productive than single spindle machines. Since in multispindle machines we have 6 "main" spindles, in the single spindle turret lathes we have 1 spindle and 1 subspindle. This means that in the most sofisticated single spindle machines, we are only able to make 4 operations simultaneously (1 front and 1 cross operation per spindle). Since multispindle lathes can work under the same scheme (2 operations per spindle), the difference in productivity is obvious. In adddition to this 6 spindles, we can work adittionally with 1 pick-up attachment, that works as a subspindle. If the part has too many operations that cannot be finished 100% in the 6 (or 8) spindles, we always have this subspindle where we can make the remaining oeprations one after the other. As a result, the difference in productivity will be given by the number of operations that have to be performed: As more operations we have to perform, more single spindles will we need to achieve the same production. If we have less operations, sometimes we can work on double production (2 parts per cycle).
2) TOOL-COST: Let's remind that operations to be perfomed are given by the part, not by the machine. Tools are the same. The tool cost per part is exactly the same if the tools that will be used in both types of machines are the same. This happens in the 99% of the situations.
3) COST OF ENERGY and COOLANTS: It is true that multispindle automatic lathes have a higher UNITARY energy consumption than standard cnc automatic lathes. Just this information is not enough by itself, since the most important is the cost per machined part. As a resume, to make precise calculations, the comparison should be made from the 5 single spindles and 1 multispindle. If we obtain the cycle times by each machine type, then we can know for a concrete part how many automatic lathes can achieve the production of 1 multi spindle. The result is evident: fewer machines (but same production) = fewer costs.
4) FLOOR SPACE: For companies that don't have too many space available, the multispindle is the right solution. This concept is sometimes related to the oppotunity cost. If your financial department is considering and evaluating different investments and they calculate the productivity per sqm, numbers are unbeatable.