CNC Machines are bound to need repair and maintenance throughout their lifetime. Depending on the machine type and types of subsystems, the machine may require daily, weekly, monthly, semi-annual, and annual preventative maintenance requirements. Regular maintenance tasks can pinpoint an underlying problem and help identify a solution before component failure.
CNC Machines are expensive, and it's essential to understand what can shorten the life of a CNC machine and what measures to put in place to ensure that they are in working condition as long as possible.
Indicators a CNC Machine is Nearing its Lifespan
If your CNC machine is in a constant state of repair, can't provide parts at the required production rate (or they are of degraded parts), or if wear and tear on the way systems and feed systems have resulted in excessive backlash, causing damage to the spindle bearings due to positioning inaccuracies; it is likely near the end of its working life.
Unfortunately, several critical components are no longer available from manufacturers, particularly in the machine control systems, due to constant upgrades and rapid obsolescence, so it is important to regularly monitor the state of your CNC machine to prevent premature failure. Other signs of wear or damage to the CNC machine may include increased bearing vibration amplitude, temperature rise, current rise in drive motor systems, etc.
Factors That Affect CNC Machine Health
Lack of Regular Maintenance Tasks. Regular maintenance tasks help keep CNC machines in top working condition. Neglecting routine maintenance tasks can lead to several problems, including decreased accuracy, increased downtime, and reduced machine lifespan.
Over time, wear and tear on the machine's components can lead to premature failure, resulting in expensive repairs or even the need for a new machine.
Uncontrolled Environmental Factors. Machine life can be negatively affected by environmental conditions. Poor machine foundations can cause frequent re-leveling and unwanted vibrations. Heat and humidity damage control components, while deep cold can affect lubrication and hydraulic systems.
Some machines are fitted with glass direct feedback scales, and thermal sensors can adjust positions based on temperature readings to maintain accuracy. Manufacturing plants often use air conditioning or air make-up systems to condition the plant for CNC machines, and machine control panels may use air conditioners or heat exchangers/fans. Optimal temperature and humidity ranges vary depending on the type of machine and are specified in the machine manuals; review each machine's manual for details.
Untrained Operators. Operator errors such as calling up the incorrect part program, loading the wrong tool types into the automatic tool changer, improperly loading the workpiece into the machine, or not adjusting the cutting coolant onto the point of cut can all impact the life of a CNC machine over time.
Develop Standard Operating Procedures, and train the appropriate staff to operate the equipment. The machine should be equipped with fail-safe controller logic, tool monitoring hardware and software, crash detection devices, and temperature sensors for best results.
Review the machine’s operator and maintenance manuals and act upon the preventative maintenance scheduled items. Perform a fault history check before the beginning of each shift to watch for outstanding items that may have been occurring. You should review machine fault logs regularly to identify recurring problems.
Improper Use of Tooling. Poor-quality tools can negatively affect part quality and increase wear on the machine and spindle, resulting in decreased effectiveness. Good quality tools, on the other hand, can increase production rates and extend tool life while keeping the machine healthy. Access to knowledgeable tooling providers is crucial for controlling processes and maximizing machine life.
Proper tooling and usage are essential for avoiding premature machine failure or damage. Store tools in a tool transport cart that prevents contact with cutting edges and clamping surfaces. Tool rooms offer secure storage for individual cutting tools in protective cases until they are loaded into tool holders, gage-length setting, and run-out inspections. The tool assemblies can then be transported back to the machine using a tool transport cart to ensure safe handling of the tool surfaces and edges.
Tips to Extend The Life Of CNC Machines
Follow a Preventative Maintenance Schedule
Follow the preventative maintenance schedule for the machine from the OEM's manuals. Clean, inspect, and repair as instructed. In addition to appropriately applying preventative maintenance, an operator can perform daily checks on sight glasses, bowl filters, filter indicators, level indicators/sensors, increase in or unusual noise level, vibration changes, reduced quality of production parts, etc.
Validate The Effectiveness Of The Machine Lubrication System(s).
Proper lubrication is crucial for maintaining a CNC machine's health and prolonging its life. Clean lubricant is key for reducing friction and wear, which can cause machine components to deteriorate over time. Verifying that the lubrication is getting to the intended wear surfaces is essential.
Audit and Record the System Values
System values, including vibration amplitude, sound readings, feed system backlash, etc., should be audited and recorded regularly. Pay close attention to sudden increases in recorded values to ensure that preventative maintenance can be performed for critical machine elements before system failure.
Use Calibration Checking Devices
Check the spring forces with calibration checking devices to verify the 'tool clamping' works correctly. If the tool clamping mechanism is not properly calibrated, it can result in poor part quality, machine damage, or even personal injury to the machine operator.
Properly Train Operators on Machine Usage
Properly trained operators and maintenance personnel will be aware of normal conditions versus other circumstances. While paying attention to machine performance abnormalities and part quality deviations, they can apply actions to prevent errors and stop a machine process before machine failures occur.
Strictly Follow Safety and Lock-Out Procedures
The most important tip to extend the life of your CNC machines and protect machine operators is to adhere to safety and lock-out procedures. Assure that all procedures are strictly followed when servicing equipment to help to avoid injury and unintended machine damage.
We Can Help With CNC Machine Maintenance and Repair
If you feel your CNC machine may be nearing the end of its working life, contact a machine manufacturer. Ingersoll CM Systems can help identify the full scope required to bring the machine to a new status. A service visit can help us determine what is needed, and we can provide a quotation for the necessary repairs. We recommend working with our service department to create a preventive maintenance program. This program can include the following:
- Regular health checks by a qualified Service Technician.
- Timely repairs on failing components and subsystems.
- Refurbishment and rebuild kits installed by our technicians.
- Complete overhaul and controller retrofit of the old CNC machine.
- Feature upgrades via retool or retrofit.
Ingersoll CM Systems also provides machine manuals and training. We offer start-up support and re-training as needed, or we will supply a field service technician to analyze machine fitness and health checks to aid the production maintenance personnel. Contact our service manager John Christian at John.christian@ingersollusa.com for more details!