MAINTENANCE ON CNC MACHINES
“What is Maintenance?” without explaining “What is maintenance in Cnc Machine Tools?” We want to start with the question. The process of reviewing the bench and equipment at certain periodic intervals is called MAINTENANCE. On the other hand, when the electronic circuit elements used in CNC machine tools are compared to those used in conventional machines, it is seen that they are in large numbers. Meticulous use and healthy working environments are required for electronic components.
With the development of benches and systems, some facilities regarding maintenance and repair have also been developed. As in all matters, the initiative in maintenance is left to the operator. Maintenance should be done as soon as possible and negativities should be eliminated. Otherwise, it is not possible to manufacture parts by running any program on such a machine.
THE IMPORTANCE OF CLEANING AND MAINTENANCE IN CNC MACHINES
Cleaning and maintenance are of great importance in CNC machine tools. The reason is that in Cnc machine tools, if cleaning and maintenance is insufficient, it suffers damage in terms of work and material. Major malfunctions cause the machine to be out of production and cause great expenses.
Fault Diagnosis occurs when faults are detected in a short time. In this diagnosis, answers should be given to the questions posed by the machine control unit. On the other hand, according to the answers of the operator, the malfunction is explained by the control unit and forwarded to you. Common malfunctions in CNC machines are as follows;
Dust
excess fat
Due to similar reasons such as humidity, heat and vibration, loosening and malfunctions occur in the joints of the circuit elements.
It is often sufficient to check these connections and install them in the appropriate position. It will be necessary for the cleaning of U parts and for troubleshooting. Mechanical impact, breaking, burning, etc. Apart from damage, malfunctions can be eliminated with very simple dusting and cleaning processes.
For the reasons explained above, it is extremely important to clean the environment where CNC machines are located. The axis movement areas of the bench must be clean and sufficiently oiled. They should be opened and cleaned when necessary. Otherwise, it is inevitable that the machine will be out of service for a long time for the simplest reasons. Today, maintenance is carried out at two levels;
A-Planned maintenance,
B-Preventive maintenance
Both levels of maintenance should be carried out by technical personnel who are experts in this field. These persons should be:
Sufficient technical and practical knowledge in the field of electronics,
certain professional experience,
digital electronics knowledge
Ability to use measuring and testing devices,
Must have sufficient technical knowledge about mini and micro computers.
Maintenance in CNC machines is schematically as follows;
WEEKLY MAINTENANCE:
In weekly maintenance, maintenance should be done with test schedules. So much so that the number of revolutions to be given to the machine spindle, feed rates, values such as minimum and maximum are subject to the test. It is necessary to solve the problems by noting the findings obtained with these tests and investigating the causes. It is checked whether all the fans on the bench and peripheral equipment provide sufficient air circulation and the perforated paper tape drive and wheels are checked. And the reader arranges the head, channel and nails.
MONTHLY MAINTENANCE:
In the monthly periodic maintenance, you should test a workpiece program by running it without removing chips, and make comparisons by monitoring the axis movements. You should check that all circuit connections are properly installed by lubricating the places that need to be lubricated manually. You should remove the casings of the measuring systems and clean the dirt and oils, if any.
SIX MONTHS MAINTENANCE
The data obtained by measuring the speed, voltage and errors of the system should be compared with the first measured values. Air, oil filters, etc. Elements are checked and cleaned and if necessary replaced with a new one.
ANNUAL MAINTENANCE:
In CNC systems, each circuit and circuit elements should be checked by looking at whether they have the best working systems. On the other hand, the cleanliness of the contact points is checked and the doors, sealing elements and connection screws are checked to see if they are tight.