Engineering Engineering Drawing Mechanical Engineering 

Analytical and Experimental Determination of Cutting Forces | Mechanics of Machining

Development of equations for estimation of cutting forces The two basic methods of determination of cutting forces and their characteristics are : (a) Analytical method : enables estimation of cutting forces characteristics : – • easy, quick and inexpensive • very approximate and average • effect of several factors like cutting velocity, cutting fluid action etc. are not revealed • unable to depict the dynamic characteristics of the forces. (b) Experimental methods : direct measurement characteristics : – • quite accurate and provides true picture • can reveal effect of variation…

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Engineering Mechanical Engineering 

Compression Causes Expansion | Materials and Mechanics

Surface tension compresses a water droplet and equivalently the effect of surface stress is to decrease the lattice parameter in metal particles. The effect of surface stress and elastic properties like Poisson’s ratio can be accentuated in lower dimensional systems like metal nanoparticles. The I.I.T. Kanpur team, using a two scale computational method and transmission electron microscopy, not only show a lattice expansion due to purely surface stress effects in a metallic system, but also discover anomalous lattice expansion in the case of very thin walled in metal nanoshells. This…

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Engineering Engineering Drawing Lathe Machine Mechanical Engineering 

Machining Forces and Merchant’s Circle Diagram (MCD) | Mechanics of Machining

Benefit of knowing and purpose of determining cutting forces The aspects of the cutting forces concerned : • Magnitude of the cutting forces and their components • Directions and locations of action of those forces • Pattern of the forces : static and / or dynamic. Knowing or determination of the cutting forces facilitate or are required for : • Estimation of cutting power consumption, which also enables selection of the power source(s) during design of the machine tools • Structural design of the machine – fixture – tool system…

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Engineering Engineering Drawing Lathe Machine Mechanical Engineering Modern Machine Shop 

Use of Chip Breaker in Machining | Mechanics of Machining

Need and purpose of chip-breaking Continuous machining like turning of ductile metals, unlike brittle metals like grey cast iron, produce continuous chips, which leads to their handling and disposal problems. The problems become acute when ductile but strong metals like steels are machined at high cutting velocity for high MRR by flat rake face type carbide or ceramic inserts. The sharp edged hot continuous chip that comes out at very high speed • becomes dangerous to the operator and the other people working in the vicinity • may impair the…

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Engineering Lathe Machine Mechanical Engineering 

Orthogonal and Oblique Cutting | Mechanics of Machining

Orthogonal and oblique cutting It is appears from the diagram in Fig. Ideal direction of chip flow in turning that while turning ductile material by a sharp tool, the continuous chip would flow over the tool’s rake surface and in the direction apparently perpendicular to the principal cutting edge, i.e., along orthogonal plane which is normal to the cutting plane containing the principal cutting edge. But practically, the chip may not flow along the orthogonal plane for several factors like presence of inclination angle, λ, etc. Figure: Ideal direction of chip…

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Engineering Engineering Drawing Mechanical Engineering 

Mechanism of Chip Formation | Mechanics of Machining

Mechanism of chip formation in machining Machining is a semi-finishing or finishing process essentially done to impart required or stipulated dimensional and form accuracy and surface finish to enable the product to • fulfill its basic functional requirements • provide better or improved performance • render long service life. Machining is a process of gradual removal of excess material from the preformed blanks in the form of chips. The form of the chips is an important index of machining because it directly or indirectly indicates : • Nature and behaviour…

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Engineering Lathe Machine Mechanical Engineering 

Conversion of tool angles from one system to another: Mechanics of Machining

Purposes of conversion of tool angles from one system to another • To understand the actual tool geometry in any system of choice or convenience from the geometry of a tool expressed in any other systems • To derive the benefits of the various systems of tool designation as and when required • Communication of the same tool geometry between people following different tool designation systems. Methods of conversion of tool angles from one system to another • Analytical (geometrical) method: simple but tedious • Graphical method – Master line…

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Engineering Mechanical Engineering 

Mechanics of Machining (Metal Cutting): Geometry of Single Point Cutting Tools

Geometry of single point turning tools Both material and geometry of the cutting tools play very important roles on their performances in achieving effectiveness, efficiency and overall economy of machining. Cutting tools may be classified according to the number of major cutting edges (points) involved as follows: • Single point: e.g., turning tools, shaping, planning and slotting tools and boring tools • Double (two) point: e.g., drills • Multipoint (more than two): e.g., milling cutters, broaching tools, hobs, gear shaping cutters etc. (i) Concept of rake and clearance angles of…

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Mechanical Engineering 

Mechanical Engineering: Basic working principle, configuration, specification and classification of machine tools

Classification of Metal, Removal Processes & Machine Tools Basic functional principles of machine tool operations Machine Tools produce desired geometrical surfaces on solid bodies (preformed blanks) and for that they are basically comprised of; Devices for firmly holding the tool and work Drives for providing power and motions to the tool and work Kinematic system to transmit motion and power from the sources to the tool-work Automation and control systems Structural body to support and accommodate those systems with sufficient strength and For material removal by machining, the work and…

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Mechanical Engineering 

Mechanical Engineering: Introduction to Manufacturing and Machining

Classification of Metal, Removal Processes & Machine Tools Manufacturing – Need and concept The progress and the prosperity of human civilization are governed and judged mainly by improvement and maintenance of standard of living through availability or production of ample and quality goods and services for men’s material welfare (MMW) in all respects covering housing, clothing, medicine, education, transport, communication and also entertainment. The successful creation of men’s material welfare (MMW) depends mainly on availability of natural resources (NR) exertion of human effort (HE); both physical and mental development and…

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