With the arrival of winter, most regions experience low temperatures, posing the greatest threat to the safety of lasers and water cooling systems—freezing. If proper precautions are not taken, freezing damage can severely and irreversibly harm both the laser and the chiller system, leading to costly losses.

To prevent unnecessary damage and expenses, it is critical to understand the principles of anti-freeze protection and take effective measures to keep laser systems and chillers safe in low-temperature environments.

1. Temperature Requirements for Stable Laser Operation

Equipment Operating Environment Requirements

For lasers to operate reliably, the surrounding environment must maintain a temperature range of 5°C to 45°C. If this requirement is not met, the laser may become unstable, or in severe cases, suffer permanent damage, such as frozen internal cooling pipelines.

Situations That Easily Cause Freezing in Lasers (including chillers):

1. Outdoor temperatures drop below 0°C, no heating equipment is available, and the laser remains idle for an extended period.
2. Even with heating equipment, if heating or electricity is shut off during holidays (e.g., Chinese New Year), the idle laser may still freeze.
3. The water chiller is placed outdoors.

(Note: These are common cases but not the only ones.)

2. Essential Anti-Freeze Measures for Lasers and Chillers

To prevent freezing damage, the following steps are strongly recommended:

(1) Keep the Water Chiller Powered On

Maintain the chiller in operation so that coolant water continues to circulate, preventing freezing inside pipelines.

(2) Add Professional Anti-Freeze Solution

• Mix anti-freeze with cooling water at a 3:7 ratio (30% anti-freeze, 70% cooling water).
• This mixture can resist freezing down to -20°C.
• Important Note: Anti-freeze cannot permanently replace cooling water. It should not be used year-round. After winter, the system must be flushed with fresh cooling water to remove anti-freeze residues.

(3) Drain the Cooling Water During Long Shutdowns

When the laser, chiller, or processing head will not be in use for long periods (e.g., holidays):
a. Turn off the power supply to the laser and chiller, and disconnect the circuit breaker.

b. Disconnect the water pipes between the laser and chiller.

c. Use compressed air (<3.5 Bar, clean and oil-free) to blow out residual water from both the laser and chiller, ensuring the system is fully drained.

3. Anti-Freeze Measures for Processing Heads, Fiber Optic Heads, and Cooling Pipelines

To protect additional components:

• Use compressed air (<3.5 Bar) to blow through the inlets and outlets of the processing head and fiber optic head, expelling any trapped water.
• Ensure auxiliary pipelines are also emptied to avoid freezing.

Conclusion

Laser freezing is a critical risk in winter. Without preventive measures, freezing can lead to irreversible damage and costly replacements. By following proper anti-freeze strategies—including continuous circulation, using professional anti-freeze solutions, and draining pipelines during downtime—you can ensure safe and stable operation of lasers and chillers throughout the winter.

Greenstone-Tech reminds all users to take preventive action before freezing occurs, protecting both equipment performance and long-term investment.