The price of deep hole drilling machines increases in two main ways, thereby enhancing the efficiency of CNC machines

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For any CNC machine tool used for deep hole drilling to operate continuously and reliably over the long term, in addition to the quality of the machine itself, it also depends heavily on proper maintenance during use, timely troubleshooting, and prompt repairs. From the perspective of improving the efficiency of CNC machines, maintenance should encompass two aspects: one is routine maintenance (preventive maintenance), which is aimed at extending the machine’s mean time between failures MTBF; the other is fault repair, whose purpose is to minimize the mean time to repair MTTR. Carrying out these two tasks is the fundamental guarantee for fully utilizing the efficiency of the equipment. To fully realize the benefits of CNC machines, it is important to carry out preventive maintenance in order to minimize malfunctions in the CNC system and increase its average time between failures. Additionally, preparations for maintenance should always be in place, so that any faults in the system can be repaired promptly, thereby minimizing downtime for repairs. This requires familiarity with the structure and performance of the equipment, knowledge of the composition and basic operations of the CNC system, an understanding of the test points on the printed circuit boards used in the system that can be utilized for maintenance, as well as mastery of their normal voltage levels and waveforms, so as to use them as a reference for analyzing faults during repairs. In addition, the technical documentation and original setup parameters of the CNC system and programmable logic controller (PLC), as well as the commonly used typical part programs, should also be properly preserved. Based on actual usage, it is advisable to stock some vulnerable spare parts, such as fuses, brushes, as well as transistor modules and printed circuit boards that are prone to failure. For spare circuit boards, they should be regularly installed in the CNC system and powered on to operate, so as to avoid malfunctions due to long-term disuse. The key to preventive maintenance is to strengthen daily upkeep and care. Generally, the following points should be followed: 1. The programmers, operators, and maintenance personnel responsible for CNC machines must be familiar with the mechanical structure of the equipment, as well as the characteristics of the CNC systems, high-voltage components, hydraulic systems, pneumatic systems, etc., as well as the specified operating conditions and processing parameters. The machine tool should be used correctly and properly in strict accordance with the requirements outlined in its operating instructions and those of the CNC control system, in order to minimize failures caused by improper operation. 2. Many systems use tape readers as input devices for programs; tape-based information such as system parameters and part machining programs is entered into the CNC system through these tape readers. If the tape reading section of the tape reader (i.e., the light-emitting and light-receiving parts of the reading head) is contaminated, it will cause errors in the information read from the tape. Therefore, the surface of the reading head, the tape pressing plate, and the surface of the tape path should be checked regularly to remove any contaminants promptly. The moving parts of the tape reader, such as the drive wheel roller, guide roller, compression roller, tension arm roller, etc., should be cleaned regularly to ensure proper lubrication. 3. Clean the air filter regularly. When the air filters installed on the doors of CNC cabinets and electrical cabinets accumulate a lot of dust, it can lead to poor circulation of cooling air inside the cabinets. Over time, this will cause the temperature inside the cabinets to rise, preventing the system from functioning properly. Therefore, regular inspections should be carried out according to the usage environment, with the unit being removed for cleaning at least once every six months. The specific method is: first remove the fastening screws, take out the core of the air filter, and use compressed air to blow away the dust on the filter element from the inside out. If the filter is dirty, it can also be gently shaken at the same time. When the above methods do not work, a neutral detergent (at a concentration of 5%) can be used for cleaning; however, rubbing should be avoided. After that, the filter element should be placed in a cool and well-ventilated area to dry. 4. Perform regular battery maintenance. In CNC devices that use CMOS memory to store system parameters, a battery is used to supply power in order to preserve these parameters in the event of a power outage. When the battery voltage is below the CMOS hold voltage, the battery can be automatically charged when the machine tool is turned on. Under normal circumstances, the battery ensures that information is retained for over 1000 hours in the event of a power outage. When the machine tool is not in use for extended periods, it should also be powered on regularly as specified in the instructions to recharge the battery. If such CNC devices display a battery failure alarm on the CRT or through indicator lights, it indicates that the voltage is too low and the battery has failed; a new battery needs to be replaced. To preserve the original data, the battery should be replaced while the power is on, and the battery polarity must not be reversed. 5. DC servo motors should be inspected and cleaned regularly. DC servo motors have brushes that come into contact with the commutator during operation, causing gradual wear due to friction. Excessive wear of the brushes can affect the motor’s performance and even cause damage to the motor; therefore, they must be checked and replaced regularly. For general machine tools such as CNC lathes, CNC mills, and machining centers, inspections can be carried out once a year; whereas for machine tools that perform frequent acceleration and deceleration tasks, such as punch presses, inspections should be conducted every two months. Inspections should be carried out with the CNC system’s power turned off and the motor fully cooled. First, remove the brush cover, take out the brushes, and measure their length; under normal circumstances. When the brush is worn down to half of its original length, it should no longer be used; a new brush of the same model must be replaced. In the second step, it is necessary to carefully check whether there are deep grooves or cracks on the arc-shaped contact surface where the brush makes contact with the commutator, as well as to check for any signs of arcing in the brush spring. If such issues are present, the surface of the commutator must be examined carefully. If the commutator is in good condition, new brushes can be installed and checked again after one month; if the aforementioned problems persist, it is necessary to consider whether the operating conditions of the motor are too harsh, resulting in a fault within the motor itself. Before installing new brushes, clean the brush holes with clean compressed air free of metal particles and moisture; make sure to blow away all the brush powder stuck to the walls of the holes. If it is difficult to blow out completely, tools such as a screwdriver can be used to assist in cleaning until the walls of the hole are entirely clean. However, care must be taken to avoid damaging the surface of the commutator and the wall of the holes with the tip of the screwdriver. Finally, install the new brushes, tighten the brush covers, and run the servo motor without load for a while to allow the surfaces of the new brushes to fit properly with the commutator. 6. Make sure to close the doors of the enclosed CNC cabinet properly. Under normal circumstances, it should be avoided to open the CNC cabinet door casually, especially when it is left open for extended periods. The air filter should be cleaned promptly. It is absolutely not advisable to use an open cabinet door for cooling, as it will result in more losses than benefits. This is because the air in the workshop contains large amounts of dust, oil mist, and metal particles. When these contaminants settle on printed circuit boards and electronic components, they can cause a decrease in the insulation resistance of those components, leading to malfunctions; in severe cases, they may even damage the components and printed circuit boards beyond repair. Especially for CNC machines in which the spindle control system is installed in a high-voltage cabinet, if the door of the cabinet is not properly closed or the sealing is inadequate, it can easily lead to damage to electrical components and result in failure of the spindle control. 7. Regularly clean the cooling system to enhance its heat dissipation performance. Some servo motors or spindle motors are equipped with forced cooling systems in their housings. If the protective screens or heat sinks of these cooling systems become dirty and hinder air circulation, the cooling capacity will inevitably decrease, leading to failures due to heat buildup. Therefore, these cooling devices should be cleaned regularly. The specific methods are as follows: if excessive dust on the protective mesh hinders ventilation, it can be removed for cleaning; when the radiators are covered in a lot of dust, they can be blown clean with compressed air, or a thin rod can be used to remove the dust from between the fins. However, care must be taken during operation to avoid crushing or deforming the heat sinks or causing them to overlap, as this could affect the cooling efficiency. The aforementioned cleaning cycle is generally once every six months, but it can be appropriately shortened depending on the specific circumstances. 8. For CNC machines that are not used for extended periods of time, the CNC system should be powered on regularly to allow it to run idle with the machine locked in place. During the rainy season in the south, where humidity levels are high, it is even more necessary to keep the equipment powered on on a daily basis, using the heat generated by the electrical components themselves to remove moisture from inside the CNC cabinet. To ensure the stable and reliable performance of the circuit. Practice has shown that machine tools that are not in use tend to develop various types of faults after periods of humid weather. If a CNC machine tool remains unused for more than half a year, the brushes of the DC servo motor should be removed to prevent the commutator surface from being corroded due to chemical reactions, which could lead to poor commutation performance or even damage to the motor. 9. For the components that move frequently on the machine tool, regular inspections should be carried out with emphasis, both from a mechanical perspective and in terms of control and drive systems. On CNC machines, many limit switches that control the movement positions are used to ensure the reliability of the machine’s operation. And the reliability of these travel switches directly affects the operational reliability of the entire machine. Furthermore, the mechanical and electrical structures of the automatic tool-changing device on machine tools are relatively complex, making them prone to failures; therefore, it is necessary to regularly check the electrical system that controls tool selection and positioning in the tool magazine, as well as the operation of the limit switches that monitor the position of the robotic arm, in order to ensure the proper functioning of the machine tool. Any CNC machine tool will inevitably experience wear and failures after long-term operation. However, the goal of routine preventive maintenance of machine tools is to extend the service life of their components, prolong the period before wear occurs, prevent unexpected serious accidents, and ensure that the machines can operate reliably for a long time. The general instruction manuals for machine tools specify the requirements for maintenance and inspection, and these should be followed strictly.