The Effect of Temperature Changes on Marking Precision and Compensation Methods

Variations in temperature are a key factor affecting the accuracy of laser marking machines. They can cause deformation of materials or shifting of the focus.By analyzing the relationship between temperature and precision, and offering practical solutions such as hardware compensation and software adjustment, the company is helping users meet the challenges posed by temperature variations and ensuring that marking quality is stable and reliable.

Why does temperature affect marking accuracy?

During the process of laser engraving, the temperature of the environment and the heat generated by the equipment itself can both have a subtle effect on the results.For example, metals expand when heated, which can cause the marking position to shift by 0.05-0.1 millimeter. The output power of a laser also changes with temperature, much like how a phone charges more slowly in the summer. This can cause the depth of the marking to vary.In particular, in factories with a wide difference in temperature between day and night, the parameters adjusted in the morning may be "out of whack" in the afternoon.

The expansion and contraction of materials with temperature changes.

The sensitivity of different materials to temperature varies greatly.Take the example of aluminum, which expands about 0.023 millimeters per meter for every 10 degrees Celsius increase in temperature. Acrylic, on the other hand, expands more than two times as much.This is why some precision parts produced in winter fail quality control tests in summer.

The laser's performance fluctuates.

The temperature at which fiber lasers operate must be kept within a range of 25 ± 3 ° C, otherwise the laser wavelength will shift, resulting in an inability to focus accurately.One user has reported that after working in a non-air-conditioned factory for four hours, the depth of the marking will decrease by about 15 %.

Techniques for monitoring temperature changes.

Don't wait until there's a problem to fix it; it's better to prevent it from happening in the first place.It is recommended that three temperature sensors be installed in key locations: the laser head, the work platform, and the environment.There are some smart temperature control modules on the market that can send real-time data to a smartphone, and automatically alert the user of any abnormality.

Economic monitoring plan.

If your budget is limited, you can try the old fashioned way: use an infrared thermometer to measure the temperature of the equipment three times a day (in the morning, afternoon and evening) and record the temperature in a table.One metal processing plant found that air conditioning vents were blowing directly on the equipment and causing periodic errors in just two months.

Three steps to temperature compensation

According to our experience of visiting over 20 companies, the most effective compensation methods are those that combine "soft" and "hard" elements.As for hardware, installing a water cooling system on the laser can have immediate results, but you have to remember to change the coolant regularly.Software compensation is more flexible, and most mainstream marking software now supports temperature-coordinate compensation algorithms.

Dynamic focal length compensation technology.

The latest solution has been to incorporate temperature sensors into the print head, and to use an electric focusing device.When temperature changes are detected, the Z axis automatically fine-tunes to compensate for focus displacement.One medical equipment manufacturer saw the read rate of its products rise from 83 % to 99.6 %.

Intelligent parameter matching.

He suggests that a table of parameters be established for different temperatures.For example, at 25 ° C the laser uses 100W power at 2000mm / s, but at 30 ° C it adjusts to 98W at 2050mm / s.There's a little trick to this: set temperature trigger conditions in the marking software, so that the preset parameter group is automatically switched when the threshold is reached.

Daily maintenance tips.

In addition to technical means, operating habits are important as well.Before starting up the machine each day, he preheats it for 15 minutes, just as one would warm up a car in winter.If the temperature drops suddenly, check to see if the lubricant has congealed.One watch parts factory insists on temperature calibration every month, and in three years has never had a batch of defective products.

Finally, I would like to remind everyone that the compensation plan should be based on the model of your own equipment.For older CO2 laser machines, the temperature of the galvanometer mirror may be more of a concern, while for UV lasers, the efficiency of the water cooling system is more important.If you really can't decide, the best thing to do is to ask the manufacturer for a white paper on temperature compensation.