1 When selecting the cutting fluid according to the requirements of the machine tool, it must be considered whether the structure of the machine tool is suitable. Some machine tools, such as multi-axis automatic lathes, gear machining machines, have been considered when designing oil-based cutting fluids, so no special device for special bearing caps is used to protect the internal mechanism of the machine from external water and steam. Most of these machines rely on oil-based cutting fluids to lubricate the moving parts in the vicinity of the cutting area, so oil-based cutting fluids must be used. If water-based cutting fluids are used, their water solubility will penetrate into the bearings and the internal structure of the machine, causing these parts to de-oil and produce accelerated corrosion wear. The penetration of water-based cutting fluid into the hydraulic system will emulsify the hydraulic oil into oil-in-water or oil-in-water emulsions, increasing or decreasing the viscosity, changing the properties of the hydraulic oil and affecting the normal operation of the hydraulic system. Therefore, for those machine tools that originally use oil-based cutting fluids, care must be taken when transferring water-based cutting fluids. If necessary, make appropriate modifications. Otherwise, the machine tool may be damaged. 2 According to the tool material selection tool steel tool: its heat-resistant temperature is about 200 ~ 300 °C, can only be applied to the general material cutting, will lose the hardness at high temperatures. Because of the poor heat resistance of this type of tool, the coolant is required to have a better cooling effect, and it is generally preferable to use an emulsion. High-speed steel: This material is a high-grade alloy steel based on chromium, nickel, tungsten, molybdenum, vanadium (some also contain aluminum), their heat resistance is significantly higher than the tool steel, the maximum allowable temperature up to 600 °C. Compared with other high-temperature resistant metals and ceramic materials, HSS has a series of advantages, in particular, it has a high toughness, is suitable for workpieces with a complex geometry and continuous and cutting processing, and high-speed steel has good machinability Sex and price are easily accepted. When using high speed steel tools for low speed and medium speed cutting, oil based cutting fluids or emulsions are recommended. In high-speed cutting, it is preferable to use a water-based cutting fluid because of the large amount of heat generated. If oil-based cutting fluids are used, more smoke will be generated and the environment will be polluted, and the workpiece will be burned easily, the quality of the machining will be reduced, and the tool wear will increase. Carbide tools: Cemented carbide for cutting tools consists of tungsten carbide (WC), titanium carbide (TiC), tantalum carbide (TaC) and 5% to 10% cobalt, and its hardness is much higher than high-speed steel. The maximum allowable working temperature of up to 1000 °C, with excellent heat resistance, in the processing of steel materials, can reduce the bonding between the chips. In the selection of cutting, the sensitivity of carbide to sudden heat should be taken into account. If possible, evenly heat the tool, otherwise it will cause chipping. In the processing of general materials, dry cutting is often used, but during dry cutting, the workpiece has a higher wet rise, which causes the workpiece to undergo thermal deformation, which affects the accuracy of the workpiece. In addition, cutting is performed without lubricant because of large cutting resistance. The power consumption is increased and the tool wear is also accelerated. Dry cutting is also cost-effective. When the cutting fluid is selected, the thermal conductivity of the oil-based cutting fluid is generally poor, and the risk of quenching the tool is lower than that of the water-based cutting fluid. Therefore, it is generally preferable to use an oil-based cutting fluid containing an anti-wear additive. When using coolant for cutting, be careful to evenly cool the tool. Before starting the cutting, it is best to cool the tool with cutting fluid. For high-speed cutting, the cutting zone is sprayed with a large flow of cutting fluid so as not to disproportionately generate blade chipping due to uneven heating of the tool, and also to reduce evaporation formation and smoke pollution due to excessive temperature. Ceramic tool: Alumina (Al2O3), metal and carbon are sintered at high temperatures. This material has better wear resistance than cemented carbide at high temperatures. Dry cutting is generally used, but uniform cooling and overheating are avoided. Water-based cutting fluids are also commonly used. Diamond tool: With extremely high hardness, dry cutting is generally used. To avoid overheating, like ceramic materials, water-based cutting fluids are used in many cases. 3 Selecting the cutting fluid according to the workpiece material The performance of the workpiece material is important for the cutting fluid and the selection. According to the literature, the material to be processed can be divided into different grades according to the difficulty of machinability, and this can be used as the basis for selecting the cutting fluid. Table 1 ranks the machinability index of a material. The index of machinability of copper under solid conditions was set at 100, and other materials were cut under the same conditions and arranged according to the relative durability of the tool obtained. Table 1 The grade of material can be divided by the cutting index. Example of material group Material cutting index The first group of ordinary cutting steel:
Non-alloy steel, low alloy steel and hardened steel (15,35,15crMn)
Free cutting steel (Y12, Y12Mn)
Construction Steel (35,60) 80 Second Group of Harder Cutting Steels:
High-alloy steel and its quenched steel (20CrMo, 42CrMo)
High chromium alloy steel (1Cr17, 4Cr13)
High chromium nickel alloy steel (12CrNi2)
Corrosion-resistant acid-resistant chromium-nickel steel (0Cr18Ni9, 1Cr18Mo10Nb)
Cast steel 50 The third group of hard-to-cut steels:
Nickel and Nickel Alloys Ni10Cr10, Ni18Cr20)
Manganese and nickel silicon steel (40CrMn2, 60Si2Mo)
Chrome molybdenum steel (20CrMo)
Silicon Steel (38Si2Mn
Titanium and Titanium Alloys Group 4 Gray and Malleable Cast Iron (HT250, KTZ450-06)
Non-alloy steel, low alloy steel and hardened steel (15,35,15crMn)
Free cutting steel (Y12, Y12Mn)
Construction Steel (35,60) 80 Second Group of Harder Cutting Steels:
High-alloy steel and its quenched steel (20CrMo, 42CrMo)
High chromium alloy steel (1Cr17, 4Cr13)
High chromium nickel alloy steel (12CrNi2)
Corrosion-resistant acid-resistant chromium-nickel steel (0Cr18Ni9, 1Cr18Mo10Nb)
Cast steel 50 The third group of hard-to-cut steels:
Nickel and Nickel Alloys Ni10Cr10, Ni18Cr20)
Manganese and nickel silicon steel (40CrMn2, 60Si2Mo)
Chrome molybdenum steel (20CrMo)
Silicon Steel (38Si2Mn
Titanium and Titanium Alloys Group 4 Gray and Malleable Cast Iron (HT250, KTZ450-06)
60~110
Group 5 Non-Ferrous Metals: Copper and Copper Alloys (ZQSn10-1) 100 to 600 Sixth Group Light Metals: Aluminum and Magnesium Alloys LF5, LF10, LDI) 300 to 2000 According to Table 1, materials with smaller cutting index are more difficult to process. When selecting the cutting fluid, the cutting fluid containing anti-wear extreme pressure additives with high activity should be selected for difficult-to-machine materials. For the easily processed materials, pure mineral oil can be used to draw other cutting fluids without additives. Machining is a complex process. Although cutting a material, when the cutting speed changes or the geometry of the cutting workpiece changes, the effect of the cutting fluid is completely different. Therefore, when selecting the cutting fluid, the machining process and the machining process must be combined. The characteristics come to comprehensive consideration.Processing Services,Parts Machining Service,Custom Single Punch Dies,Custom Progressive Die
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