Общий каталог Mitsubishi 2020 - 2021 - страница 37

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SAFETY OF CUTTING TOOL PRODUCTS y 1. Use of Cutting Tool Products Packages of Mitsubishi products carry a safety warning label. However, tools are not labeled with detailed warning instructions. Please read the "Safety of Cutting Tool Products" in this catalog before handling cutting tool products and cemented carbide materials. Moreover, as a part of your workers' safety education, please notify the contents of the "Safety of Cutting Tool Products" to all workers. y 2. Basic Characteristics of Hard Tool Materials aIn Terms of "Safety of Cutting Tool Products" Hard Tool Materials : General term for tool materials like cemented carbide alloy, cermet, ceramics, sintered CBN, sintered diamond, high speed steel and alloy steel, etc. aPhysical Characteristics Appearance : Varies depending on the type of material, e.g. gray, black, gold, etc. Smell : None Hardness, Specific Gravity : Hard Tool Materials Hardness (HV) Specific Gravity Hard Tool Materials Hardness (HV) Specific Gravity High Speed Steel (HSS) 200 ─ 1200kg/mm2 7─9 Sintered CBN 2000 ─ 5000kg/mm2 3─5 Cemented Carbide 500 ─ 3000kg/mm2 9 ─ 16 Sintered Diamond 8000 ─ 12000kg/mm2 3─5 Cermet 500 ─ 3000kg/mm2 5─9 Alloy Steel 200 ─ 1200kg/mm2 7─9 Ceramics 1000 ─ 4000kg/mm2 2─7 Diamond Electroforming Product 8000 ─ 12000kg/mm2 3─5 aConstituents Carbide, nitride, carbon nitride, oxide, W, Ti, Al, Si, Ta, B, V and metals such as Fe, Co, Ni, Cr, Mo. y 3. Safety of Cutting Tool Products uHard tool materials have a large specific gravity. Thus, they require special attention as heavy materials when the size or quantity is large. uHard tool materials generates dust and mist during grinding operations or heating. This dust and mist can be harmful to the human body when coming in contact with the eyes or skin, or if substantial quantities are swallowed. When grinding and machining, it is recommended to use local exhaust ventilation and respirators, a dust protective mask, glasses, gloves and so on. If dust makes contact with the hands, thoroughly wash the affected area with soap and water. Don't eat in the exposed area, and wash hands thoroughly before eating. Remove dust from the clothing by a cleaner or washing, but don't shake off. uCobalt dust can affect the skin, respiratory organs and heart through repeated or prolonged contact. uFor further information, please refer to SDS (Safety Data Sheet). Home page: http://www.mmus-carbide.com/download/safety/ y 4. Handling Cutting Tool Products uSurface conditions affect toughness of cutting tools. Therefore, use a diamond grinding wheel for finishing. uHard tool materials are extremely hard and brittle at the same time. Thus, they may be broken by shock and tightening with excess force. uHard tool materials and ferrous materials have different thermal expansion ratios. Shrinkage or swell fit products may suffer from cracks when applied temperature is higher or lower than the appropriate temperature for the tool. uPay special attention regarding storing hard tool materials. Toughness of hard tool materials is lowered when they corrode due to coolant and other liquid. uWhen brazing hard tool materials, if the temperature is too high or too low from the melting point of the brazing material, loosening and breakage may occur. uAfter regrinding cutting tools, make sure that there are no cracks. uMachining hard tool materials on EDM may cause cracks on the surface due to remaining electrons resulting in lowering the toughness. Eliminate cracks by grinding, etc. 16