Understanding Metalworking Fluids: Types, Uses, and Safety Considerations

Many metalworking techniques create a great deal of friction and metallic byproducts. Metalworking fluids made of various substances are used to lubricate, clean and cool metal work pieces during this process. Most industrial metalworking processes require metalworking fluids, especially in abrasive processes such as grinding. Fluids can be liquid or grease-like and can consist of a wide variety of petroleum, water-based and synthetic materials. There are many health concerns associated with metalworking fluids because of substance composition, as well as related safety and handling precautions.

Metalworking fluids are used during machining for a few key purposes. Many of the machining processes create immense heat between the cutting tool and the metal work piece, and these fluids often cool down the metal work piece and cutting tool. Another benefit of this process is that both the cutting tool and the metal become lubricated. A fluid also may be used to clean off the metal pieces machined from the work piece.

Many of the processes associated with metalwork can require metalworking fluids, especially in high-volume or high-speed machines. CNC metalworking, in which a computer controls the cutting tool, usually uses them for processes such as turning, grinding and sawing. While industrial processes most often use them, even consumer-based metalworking machines might require fluids of various compositions.

Generally, metalworking fluids are petroleum, water or synthetic based. Many factors affect which fluid combinations must be used, including the types of metal, the types of cutting tools, and the size of a work piece. Liquids also can be thickened with soap or non-soap agents to create a more viscous grease-like material useful for certain types of machining. The materials used to create metalworking fluids, however, raise some health concerns.

Exposure to metalworking fluids is potentially dangerous for a few reasons. The chemicals and organic compounds used can become contaminated and also can hold small pieces of metal. Getting this material on skin can cause irritation, rashes and more serious skin problems. Additionally, if a metalworking fluid is temporarily turned to mist during the machining process, it is possible to inhale the fluids, which can lead to respiratory complications. Contamination also can occur during storage, and fluids should be stored according to manufacturer instructions.

Contaminated, used or generally hazardous metalworking fluids can be handled safely. Most manufacturers include instructions on safe handling, and some industry-based organizations offer comprehensive instructions. Gloves, chemical filter masks and protective clothing are basic tools used to prevent hazardous conditions.

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Link to Sources

• https://www.cdc.gov/niosh/topics/metalworking/