Solutions to problems such as odor, corrosion, foam and rust of cutting fluid in use
September 18, 2023
Cutting fluids are widely used in cutting processes due to their functions such as cooling, lubrication, cleaning, and rust prevention. The cutting fluid often has problems such as deterioration, odor, corrosion, foam generation, workpiece rusting, etc. In combination with the experience of metalworking fluid and additive development research and field application, the problems and countermeasures in the use of cutting fluid are discussed below.
1. For the rusting of workpieces caused by Fully Synthetic Cutting Fluid in summer Due to the lack of oil in fully synthesized cutting fluids, many manufacturers choose inorganic salts as their anti rust additives. In summer, the weather is hot and the water evaporates greatly. In addition, the operators do not add cutting fluids in a timely manner, resulting in the inorganic salts in the liquid tank reaching a saturated state, which precipitates and adheres to the surface of the workpiece. This not only fails to prevent rust, but also brings great trouble to subsequent cleaning. So appropriately reducing the amount of inorganic salt added and adding organic rust inhibitors can improve this. Organic rust inhibitor tricarboxylic acid has advantages such as good rust resistance, low foaming, good hard water stability, and no irritation to the skin and mucous membranes when used in solutions within the usual concentration range. Not only does it have excellent rust prevention effect, but the system is also more stable. 2. Is the "burn" generated during grinding insufficient cooling or lubrication The problems such as burns and blueness generated during grinding are caused by local high temperatures during grinding. Grinding is a high-speed cutting process that generates instantaneous high temperatures at the grinding point. Therefore, burn problems often occur during grinding processing. The most direct way is to improve the lubrication conditions in the grinding area and reduce the instantaneous high temperature at the friction point, which is more effective. So if burn problems occur, the main solution is to improve the lubricity of the grinding fluid. Self emulsifying ester is a multifunctional functional group self emulsifying water-soluble ester that has three basic functions in the same product: lubrication, emulsification, and hard water stability. This product is particularly suitable for both fully synthetic and semi synthetic cutting fluids, with excellent interface lubrication, rust prevention, and cleaning effects. It effectively reduces tool adhesion, improves product smoothness, reduces tool wear, and has strong resistance to hard water.
3. For the problem of blackening and mold on the surface of workpieces during the processing of aluminum parts Due to the relatively active chemical properties of aluminum, it is prone to chemical reactions with acids and bases, resulting in corrosion, rust spots, blackening, and mold. When dealing with such problems, the first consideration is that the pH value of the cutting fluid should not be too high and should be maintained between 8.5 and 9.0. The selected rust inhibitor needs to have corrosion inhibition and stable pH value. It is best to choose rust inhibitors that can form a protective film on the surface of the workpiece, such as phosphate esters, sodium silicate, etc. 4. Reasons for many foam when using cutting fluid
Cutting fluid components contain many surfactants, commonly known as cleaning agents. These cleaning agents will produce a lot of foam when used, which is adverse to machining. It can pollute the processing environment and cause inconvenience to production personnel. Leakage from the machine tool can also reduce the cleaning ability of the cutting fluid. At this point, a small amount of defoamer can be added (silicone oil has the fastest effect, polyether has strong persistence, and can suppress foam) to remedy the situation.
5. Odor problem during the use of cutting fluid
Cutting fluid can be divided into emulsified oil (emulsion), semi synthetic (micro lotion) and fully synthetic. Due to the large amount of mineral oil contained in emulsified oil, it provides a breeding ground for bacteria, fungi, and molds. If no fungicides are added, a large number of bacteria will grow in a short period of time, causing odor. Choosing suitable fungicides can effectively solve the problem.
