Workshops become hot and humid, placing machine tools under demanding operating conditions. Without proper preventive maintenance, high temperature and moisture can adversely affect machining accuracy, electrical systems, lubrication performance, and overall equipment reliability.

During the rainy season, high temperature and humidity can pose significant challenges to machine tools, affecting machining accuracy, electrical systems, lubrication performance, and structural components. How can we minimize these risks, maintain stable equipment operation, and ensure uninterrupted production? This machine tool maintenance guide provides practical recommendations to help keep your equipment running reliably in harsh environmental

1.Warning: Four Hidden Risks to Machines During the Rainy Season  

Long-term operation of machine tools under high temperature and high humidity conditions may result in gradual performance degradation and potential damage to critical components.

①Gradual Loss of Machining Precision:Humidity fluctuations may cause minor thermal expansion and contraction of machine tool structural components. Meanwhile, high humidity can lead to condensation on precision measuring devices such as linear scales and encoders, causing signal acquisition errors and affecting machining accuracy, which may result in inconsistent workpiece dimensions.

②Electrical System Deterioration:Moisture can cause oxidation of electrical contacts, reduced insulation performance, PCB short circuits, and frequent inverter alarms. These issues may not result in immediate machine downtime, but they can gradually reduce equipment reliability and increase the risk of electrical failures or fire hazards over time.

③Metal Corrosion:Prolonged exposure to humid conditions can accelerate corrosion on exposed metal surfaces, including worktables, spindle tapers, and tool interfaces. Even minor rust can affect clamping stability and tool-changing accuracy, while long-term corrosion may lead to permanent damage to critical machine components.

④Reduced Lubrication and Cooling Performance:Excessively high ambient temperatures can significantly reduce the heat dissipation efficiency of cooling systems, making it difficult to maintain proper temperatures for critical components such as spindles and drives. In extreme cases, cooling units themselves may become overloaded and fail.

2.Preventive Measures: Three Essential Lines of Defense.

Monitor machine conditions continuously and address abnormalities promptly.

①Maintain Proper Temperature and Humidity:

Maintain workshop temperatures between 22–28°C and relative humidity between 30% and 60%. Industrial air conditioning systems and dehumidifiers are highly recommended during the rainy season. If humidity exceeds 60%, increase dehumidification measures promptly to prevent moisture-related issues. (During the rainy season, it is recommended to maintain humidity below 30%).

②Protect the Electrical System: Prevent Moisture-Related Failures

Special attention should be given to the protection of electrical cabinets. Regularly inspect the cabinet door sealing strips to ensure reliable sealing performance. Place sufficient desiccants or moisture-proof packs inside the cabinet and replace them periodically.

For machines that remain idle for extended periods, keep the cabinet heater or ventilation fan operating to actively reduce moisture accumulation, prevent condensation, and minimize the risk of electrical failures caused by high humidity.

③Warm-Up Before Operation Is Essential

At the beginning of each working day, a proper machine warm-up procedure should be performed. Run the spindle at low speed and move the axes reciprocally to generate internal heat, reduce surface moisture, and promote uniform lubrication film distribution, ensuring stable machining accuracy.

Under high-temperature and high-humidity conditions, lubricants are more susceptible to moisture absorption and deterioration. Therefore, lubricant replacement intervals should be shortened according to the maintenance manual. Ensure that moving components such as guideways and ball screws are lubricated with specified lubricants to prevent water contamination and oil emulsification, maintaining reliable lubrication performance 

3.Five Steps to Recover a Machine Tool After Water Ingress

If a machine is exposed to water or flooding, do not restore power or attempt to restart the equipment. Contact SNSTC’s after-sales service team immediately for professional assistance.                                                                                                                                                                                             

Step 1: Shut Down and Disconnect Power

If any abnormal condition is detected or workshop humidity exceeds the recommended range, stop the machine immediately and disconnect the main power supply. This helps prevent further damage caused by operation under abnormal conditions.

Step 2: Professional Inspection Comes First — The Most Important Step

Do not attempt to start or operate the machine tool by yourself. Contact SNSTC’s after-sales service team immediately and arrange for professional engineers to visit the site for a thorough assessment..

Step 3: Thorough Cleaning and Drying

Under the guidance of service engineers, or while waiting for professional support, preliminary treatment can be carried out. Use clean cotton cloths or non-woven fabric to carefully wipe away condensation and surface moisture from all parts of the machine tool.

Pay special attention to critical areas such as guideways, ball screws, the interior of the electrical cabinet, and ventilation filter screens of the top-mounted resistor box. Low-temperature industrial air blowers may be used to assist the drying process, ensuring that no residual moisture remains.

Step 4: Rust Prevention and Lubrication

After all components are completely dry, apply anti-rust treatment and lubrication to moving components such as guideways, ball screws, spindle assemblies, and sliding surfaces.

For metal surfaces with minor corrosion, carefully remove rust using fine sandpaper or a dedicated rust remover before applying protective oil or grease to restore the protective layer.

Step 5: Controlled Power-On Verification

Only restore power after confirming that all components are completely dry and the electrical system is functioning normally. Perform a low-speed no-load test and verify axis homing, limit functions, and alarm status.

Resume normal machining only after stable operation is confirmed, with no abnormal noise or system alarms.

Safety First -Prevention Is the Best Protection

Successful machine tool maintenance during the rainy season depends on three key principles: prevention, monitoring, and timely maintenance. Always prioritize personnel safety and implement preventive measures systematically.

If abnormal conditions or emergencies occur, do not energize the machine. Contact qualified service engineers immediately for professional assistance.

With proper preventive maintenance and timely response, your machine tools can continue to deliver stable, reliable, and high-precision performance throughout the rainy season.

SNSTC 24-Hour Service Hotline：+86 177 2119 5368

We are always ready to support you, protect your equipment, and help keep your production running smoothly.