Environmental Impact of CNC Machining

CNC machining is nowadays extensively used in society. However, do you know how many pollution will CNC machining produce while working? Do you know the categories of pollution CNC machining will produce in total? How can we reduce the pollution it produce? This short essay will talk about the questions asked above.

List: 1. Categories of Pollution CNC Machining Produce

         2. Ways to Reduce Pollution CNC Machining Produce

Categories of Pollution CNC Machining Produce

• Noise Pollution

Noise is the sound produced by the sound body when it is making random vibrations. The sound is generated by the vibration of the object and propagates in a certain medium (such as solid, liquid, gas) in the form of waves. The so-called noise pollution is caused by man-made since the industrial revolution. The creation and use of various mechanical equipment has brought prosperity and progress to mankind, but at the same time it has produced more and more and more powerful noise.

The main drive system of CNC machine tools mainly relies on gears to complete the shifting and transmission. Therefore, the gear mesh transmission is one of the main noise sources. What’s more, the assembly, preload, concentricity, lubrication conditions, and the amount of load acting on the bearing, radial clearance, etc. of the bearing and the journal and the bearing hole all have a great influence on the noise. Moreover, the manufacturing deviation of the bearing itself largely determines the noise of the bearing.

• Iron dust pollution

In the operation process of CNC machining, the use of cutting tools will produce iron dust pollution, but the harm is not great. The metal dust particles produced by this method are larger, not easy to float, less harmful to inhalation, and does less harm to people’s body than noise pollution.

• Work fluid contamination

The most commonly used lubricants in the industry are usually gear oil, hydraulic oil, turbine oil, compressor oil, etc. After the oil has been in the lubrication system for a period of time, the oil is affected by the ambient temperature difference, light, heat and oxygen. It is affected by the shearing action to produce mechanical impurities. It will cause thermal decomposition, oxidation and polymerization reaction for a long time to produce oxides, colloids and asphaltenes dissolved in oil, which will make the oil turbid, darken and even darken, causing flashing. The point and kinematic viscosity decrease, moisture and mechanical impurities rise, and oil contamination requires replacement of new oil to ensure the normal operation of the lubrication system. During CNC machining, when turning parts, most of them will add alkaline working fluid, which will cause pollution when exposed for a long time.

Ways to Reduce Pollution CNC Machining Produce

• CNC machine tools can replace the cutting fluid with nitrogen. Nitrogen is the most abundant component in the atmosphere. Liquid nitrogen is a by-product of the oxygen industry and is rich in resources. Using liquid nitrogen as a cutting fluid, it is directly volatilized into nitrogen to return to the atmosphere after use, and does not produce any pollutants. From an environmental point of view, it is a promising alternative to cutting fluid.

• In order to improve the performance of lubricating oil, extend the oil change interval and reduce equipment wear, the gearbox dialysis machine can effectively reduce the oil pollution caused by insoluble particles, oil oxidative degradation products and moisture, by using the original oil supply and drainage pipeline. To achieve the purpose of extending the life cycle of the oil and improving the life of the gearbox. At the same time, by monitoring the pressure and temperature in the system in real time, the operating condition of the gearbox can be understood to ensure the safe and stable operation of the gearbox.

• The types and quantities of pollutants produced by different CNC cutting processes are quite different. When conditions permit, mature hidden arc welding should be used instead of open arc welding, which can greatly reduce the pollution level of pollutants.

•  High-level CNC cutting workers can skillfully and flexibly implement operational regulations during the CNC cutting process and make corresponding technical adjustments. Compared with unskilled workers, the amount of dust is reduced by more than 20%, the CNC cutting speed is 10% faster, and the quality of CNC cutting is good.

• Under the premise of determining the production process, equipment with high degree of mechanization and automation should be selected. Low-dust and low-toxic equipment should be used to reduce smoke concentration and toxicity. When purchasing new equipment, attention should be paid to the environmental performance of the equipment, and more integrated equipment equipped with purification components should be selected.

From this essay we can know that CNC machining will cause several pollution to the environment if we do not choose a proper device. In order not to produce much pollution, it is necessary for us to choose the devices which is environmentally-friendly.