Cutting fluid is a kind of industrial liquid used to cool and lubricate tools and workpieces in the process of metal cutting and grinding. Cutting fluid is composed of a variety of super functional auxiliaries by scientific combination, and has good cooling performance, lubrication performance, rust prevention performance, oil removal cleaning function, anti-corrosion function, easy to dilute characteristics.
Cutting fluid to overcome the traditional soap-based emulsion summer odor, difficult to dilute in winter, poor rust effect of the problem, no adverse effect on lathe paint, suitable for black metal cutting and grinding processing, is the most advanced grinding products.
Classification of cutting fluid:
The water-based cutting fluid can be divided into emulsion, semi-synthetic cutting fluid and fully synthetic cutting fluid.
Emulsion is a water-soluble cutting fluid with mineral oil as the base oil only.
Semi-synthetic cutting fluid is a water-soluble cutting fluid containing both mineral oil and chemical synthetic base oil.
The fully synthetic cutting fluid is a water-soluble cutting fluid that uses only chemically synthesized base oil (that is, no mineral oil).
Each type of cutting fluid will contain a variety of additives in addition to the base oil: rust inhibitor, non-ferrous metal corrosion passivator, defoamer, etc.
Some manufacturers will have a classification of microemulsions, usually considered to be between the emulsion and semi-synthetic cutting fluid category.
The diluent of the emulsion is milky white in appearance; The diluent of semi-synthetic liquid is usually translucent, and some products are milky white; The diluent of a fully synthetic solution is usually completely transparent like water or slightly colored.
The role of cutting fluid
Friends in the factory or production workshop know that when the workpiece is grinding, the temperature in the grinding area will rise, forming a high temperature area, this phenomenon will make the grinding wheel wear, the surface integrity of the parts deteriorates, but also make the parts processing accuracy is not easy to control, how to avoid this phenomenon, that is, the grinding fluid is injected into the grinding area to reduce the grinding temperature.
The main function of cutting fluid is divided into four categories: 1, lubrication; 2. Cooling effect; 3. Cleaning effect; 4, anti-rust effect.
First, lubrication
The lubrication effect of cutting fluid in the cutting process can reduce the friction between the front tool surface and the chip, and the friction between the back tool and the machined surface, forming a part of the lubricating film, thereby reducing the cutting force, friction and power consumption, reducing the surface temperature and tool wear of the friction part of the tool and the workpiece blank, and improving the cutting performance of the workpiece material. In the grinding process, after the grinding fluid is added, the grinding fluid penetrates into the grinding wheel workpiece and the abrasive particles and the abrasive chips to form a lubricating film, which reduces the friction between the interface, prevents the abrasive cutting edge from wearing and adhering to the chips, thereby reducing the grinding force and friction heat, improving the durability of the grinding wheel and the surface quality of the workpiece.
Second, the cooling effect
The cooling effect of the cutting fluid is to take the cutting heat away from the tool and the workpiece through the convection and chemical interaction between it and the cutting tool and the workpiece. Thus effectively reduce the cutting temperature, reduce the human deformation of the workpiece and the tool, maintain the hardness of the tool, improve the processing accuracy and the durability of the tool. The cooling performance of cutting fluid is related to its thermal conductivity, specific heat, heat of vaporization and viscosity. The thermal conductivity and specific heat of water are higher than that of oil, so the cooling performance of water is better than that of oil.
Third, cleaning effect
Cleaning In the metal cutting process, the cutting fluid is required to have a good cleaning effect, remove the generated chips, grinding chips and iron powder, oil and sand, prevent the machine tool and workpiece, tool stain, so that the cutting edge of the tool or grinding wheel to keep sharp, will not affect the cutting effect, for oil-based cutting oil, the lower the viscosity, the stronger the cleaning ability. Especially the cutting oil containing light components such as kerosene and diesel, the better the permeability and cleaning performance. Water-based cutting fluid containing surfactants, the better the cleaning effect, because it can form an adsorption film on the surface, prevent particles and mud adhesion to the workpiece, tools and grinding wheels, while it can penetrate into the particles and mud adhesion interface, separate it from the interface, with the cutting fluid away, to keep the cutting fluid clean.
Fourth, anti-rust effect
In the process of metal cutting, the workpiece should be corroded by contact with corrosive media such as mud caused by the decomposition or oxidation of the cutting fluid components, and the surface of the machine tool parts in contact with the cutting fluid will also be corroded. In addition, when the workpiece is temporarily stored after processing or during the flow process between processes, the cutting fluid is also required to have a certain anti-rust ability to prevent corrosion of metals by corrosive substances such as environmental media and mud in the remaining cutting fluid. Especially in the wet and rainy season, more attention should be paid to anti-rust measures between processes.
1, cutting fluid formula
The main ingredients of cutting fluid formula are: ethylene glycol, sodium tetraborate, sodium metasilicate, sodium phosphate.
Glycol: Ethylene glycol Glycol is also known as "ethylene glycol", "1, 2-ethylene glycol", or EG. Which is the simplest diols.
Sodium tetraborate: Sodium tetraborate, or borax, molecular formula Na2B4O7·10H2O, is a very important boron-containing mineral and boron compounds.
Sodium metasilicate: Sodium metasilicate is a low molecular crystal prepared by the hydrothermal reaction of ordinary blister alkali and caustic soda, and the commodity has no water, pentahydrate and nine hydrates.
Sodium phosphate: Sodium phosphate (chemical formula: Na3PO4) is a phosphate, which is an inorganic compound.
2, emulsion cutting oil formula
The main ingredients of emulsified cutting oil formula are: sodium petroleum sulfonate, polyoxyethylene alkyl phenol ether, chlorinated paraffin, lead naphthenate, triethanolamine oleic acid soap, high speed machinery oil, sodium tolate, sodium petroleum salt, synthetic fatty acid, polyethylene glycol, industrial machinery oil.
Sodium petroleum sulfonate: Molecular formula: R-SO3NA (R=C14 ~ C18 alkyl); The structural formula is: RSO3Na, where R is a straight chain aliphatic alkyl with an average of 14 to 18 carbon atoms; Solubility: Dissolved in water to form a translucent liquid, acid base and hard water are relatively stable.
Chlorinated paraffin: chlorinated paraffin is a chlorinated derivative of paraffin hydrocarbon, with low volatility, flame retardant, good electrical insulation, cheap and other advantages, can be used as flame retardants and PVC auxiliary plasticizers.
Lead naphthenate: The preparation method is obtained by the double decomposition of sodium naphthenate and lead acetate. Naphthenic acid was first heated with water to 90-100℃, and then 30% sodium hydroxide solution was slowly added for saponification until the solution was transparent, and sodium naphthenate was obtained. Then the crude product was obtained by double decomposition and replacement with lead acetate, and the finished lead naphthenate was obtained by water washing and heating and dehydration.
Triethanolamine oleic acid soap: oleic acid soap has good cleaning ability for animal and plant oil, mineral oil, oil, paraffin, lubricating oil, etc., and has good anti-rust ability.
High-speed mechanical oil: high-speed mechanical oil is also known as high-speed spindle oil. A light, low-viscosity lubricating oil obtained by refining petroleum fractions with sulfuric acid or solvents and adding antioxidants.
Synthetic fatty acids: Synthetic fatty acids are fatty acids obtained by chemical synthesis of petroleum products. Used as raw material for making soap. Its carbon number is 10 to 18, and the lower carbon number is used in other industries.
Polyethylene glycol: non-toxic, non-irritating, has good water solubility, and has a good compatibility with many organic components.
3, anti-rust extreme pressure emulsion oil formula
The main components of anti-rust extreme pressure emulsion oil formula are: chlorinated paraffin, sulfurized oleic acid, barium petroleum sulfonate, oleic acid, triethanolamine, mechanical oil.
Chlorinated paraffin: chlorinated paraffin is a chlorinated derivative of paraffin hydrocarbon, with low volatility, flame retardant, good electrical insulation, cheap and other advantages, can be used as flame retardants and PVC auxiliary plasticizers.
Petroleum barium sulfonate: Petroleum barium sulfonate is the most widely used corrosion inhibitor in China. According to different conditions of use, the general addition amount is 1-10%. It has excellent resistance to moisture, salt spray, salt water and water displacement, and has excellent anti-rust properties for a variety of metals.
Oleic acid: Oleic acid is a monounsaturated Omega-9 fatty acid found in plants and animals. Chemical formula C18H34O2(or CH3(CH2)7CH=CH(CH2)7COOH). Hydroaddition of oleic acid to stearic acid.
Triethanolamine: The content of triethanolamine in industrial products is more than 80%, and the rest contains less than 1.0% water, less than 2.5% ethanolamine and 15% diethanolamine, and a small amount of polyethylene glycol and other impurities.
Machine oil: lubricating oil of general quality obtained from petroleum lubricating oil fractions by dewaxing, solvent refining, and clay treatment, usually with only antioxidant additives.