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Categories of Cutting Fluids in Machining

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Practically all cutt ing fluids presently in use fall into one of four categories: Straight oils Soluble oils Semisynthetic fluids Synthetic fluids S traight oils are non-emulsifiable and are used in machining operations in an undiluted form. They are composed of a base mineral or petroleum oil and often contains polar lubricants such as fats, vegetable oils and esters as well as extreme pressure additives such as Chlorine, Sulphur and Phosphorus. Straight oils provide the best lubrication and the poorest cooling characteristics among cutting fluids. S ynthetic Fluids contain no petroleum or mineral oil base and instead are formulated from alkaline inorganic and organic compounds along with additives for corrosion inhibition. They are generally used in a diluted form (usual concent ration = 3 to 10%). Synthetic fluids often provide the best cooling performance among all cutting fluids. S oluble Oil Fluids form an emulsion when mixed with water. The concentrate con
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Cutting Fluid Effects in Machining

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The primary functions of cutting fluids in machining are : Lubricating the cutting process primarily at low cutting speeds Cooling the workpiece primarily at high cutting speeds Flushing chips away from the cutting zone Secondary functions include: Corossion protection of the machined surface enabling part handling by cooling the hot surface Process effects of using cutting fluids in machining include: Longer Tool Life Reduced Thermal Deformation of Workpiece Better Surface Finish (in some applications) Ease of Chip and Swarf handling 
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Introduction to a cutting Fluid

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Cutting Fluid Cutting fluid is a type of  coolant  and  lubricant   designed  specifically for  metalworking  processes, such as  machining  and stamping. There are various kinds of cutting fluids, which include oils, oil-water  emulsions , pastes, gels, aerosols (mists), and air or other gases. They may be made from petroleum distillates,  animal fats ,  plant oils , water and air, or other raw ingredients. Depending on context and on which type of cutting fluid is being considered, it may be referred to as cutting fluid, cutting oil, cutting compound, coolant, or lubricant. Most metalworking and machining processes can benefit from the use of cutting fluid, depending on workpiece material. Common exceptions to this are  cast iron  and  brass , which may be machined dry (though this is not true of all brasses, and any machining of brass will likely benefit from the presence of a cutting fluid)
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Introduction to Universal Grinding Machine

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Grinding: Grinding is a process carried out with a grinding wheel made up of abrasive grains for removing very fine quantities of material from the work piece surface. The required size of abrasive grains are thoroughly mixed with the bonding material and then pressed into a disc shaped of given diameter and thickness. Grinding process is used for two reasons (i)          Higher value of surface finish and accuracy that cannot be provided with the machining process. (ii)        Hard and brittle materials that cannot be machined or it is uneconomical to use machining   Grinding wheel A grinding wheel is made of abrasive grains held together by a bond. These grains cut like teeth when the wheel is revolved at high speed and is brought to bear against a work piece. The properties   of a wheel that determine how it acts are the ginding parameters including the kind and size of an abrasive matereial, how closely the grains are packed together and the type and amount of the b
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Parts of Vertical Milling Machine

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Parts of Vertical Milling Machine The vertical knee mill is the most common milling machine found in machine shops today. Therefore it will be used as an example to describe the general parts of all mills. Head                The head (drive) is that part of the drive system that transforms electrical power from a motor to mechanical power in the spindle. The drive system also allows the machinist to change the speed of the spindle (RPM) and therefore the cutting tool. The quill moves vertically in the head and contains the spindle in which cutting tools are installed. Column                The column is the most important part which is mounted on the base and acts as a support and holding device for all the other parts of a milling machine. It acts as a support for table and all feed mechanisms. The column should be rigid enough to sustain all the forces produced due to the drilling action of the tool. The head and worktable are mounted with column. Work table It
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Introduction to a Milling Machine

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Milling Machine A milling machine is a machine tool used for the shaping of metal and other solid material. Unlike a drill press, in which the workpiece is held stationary and the drill is moved vertically to penetrate the material, milling also involves movement of the workpiece against the rotating cutter, the latter which is able to cut on its flanks as well as its tip. Milling machines may be manually operated, mechanically automated, or digitally automated via computer numerical control (CNC).
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Tool Holding Devices in Drill Machine

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Tool-Holding Devices: Drill press spindle provides means of holding and driving cutting tool.End may be tapered or threaded for mounting drill chuck. Most common devices are used in Drill presses:       Drill chucks       Drill sleeves        Drill sockets Drill Chucks: Most common devices used for holding straight-shank cutting tools. Most contain three jaws that move simultaneously when outer sleeve turned. Hold straight shank of cutting tool securely. Two common types               Key   Keyless     Drill sleeves:                        Used to adapt cutting tool shank to machine spindle if taper on tool is smaller than tapered hole in spindle   Drill sockets:   Used when hole in spindle of drill press to small for taper shank of drill.  Used also as extension sockets.
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