Application of Machine Tools - Report Example

Application of machine tools College Machine tools application refers to the process of block or metal casting using sharp edged tools in order to create a section. The process takes into account a variety of skill and the use of a wide range of tools and specialized machines. The machines used in the metal cutting process include shearing machines, drilling machines along with electric discharging machines. Tools however encounter certain challenges that pose risks towards the safety of those handling them and could be dangerous. There is need to address to the safety and efficiency of machines in general as a precautionary measure. The challenges of machinery are such as faster acceleration or deceleration rates, complex input or output interfaces, high-speed operations and low maintenance durability, high speed and position accuracy and constant high torque productions and continuous operations (Weck 1984). Axis conventions of the center lathe and milling machine. Aids in generating tools by use of tool movement, forming shapes using tool shapes separately or by incorporating the two procedures (generation and formation of shapes) are basic ways of turning on the center lathe. The following observations made in each case of use. Shape generation outcome is determined by the movement of the tool and never by the shape of the tool. Forming: in the production of a shape through forming, the shapes of the tool used determine the resulting shape of the tool being casted. Forming and generation: these combinations are useful in shape production in a single operation. This technique makes the process of making unique shapes very easy, while avoiding alterations. (Cook, 1995) In CNC machines, the Cartesian plane of coordinates used for programming coordinates, the axes however have certain variations such as follows: The convention that the axis aligned with the spindle are to be designed “Z” are followed by the turn centers. The axis at the right angle to the spindle has the designation “X.”Taking note of each axis’ direction, positive X points toward the back of the machines while positive Z points to the right of the spindle, this is because the typical CNC turning center is constructed with the tool mounted on the opposite side of the operator (Mansfield 1977). Lathes differ from mills in their purpose since they primarily produce cylindrical pieces as screw threads and shafts, tubes and rings. The designation of CNC coordinate programming differs with that of the milling machine tool that is conventional and does not follow the Z and X coordinate system like the CNC. Drives associated with the center lathe and vertical milling. A lathe center is useful in supporting longer pieces of work. The lathe consists of two posts and a cut off and holder that are useful in separating the complete part from the rest of the body and is thus called a ‘parting tool.’ The tool comprises of a steel cutting slender tool of high speed that mounts on a special holder. The blade whose thinness is (0.40” or 1mm) enhances easy feeding into the part while reducing the waste material. A milling machine is devised to remove metal by a revolving cutting tool called a milling cutter. It can be useful in to sloting, boring, and divide circular milling and drilling. The horizontal and vertical classifications for milling machines are used to indicate the axis of the milling machine. The following is an image of a vertical milling machine (Devore et al 1979). Restraining six degrees of freedom of a rigid object using a machine vice and a 4jack lathe chuck. The degree of freedom of a system id dependent on the number of independent variables that are required to completely identify the configuration of the mechanical system. It can also be defined as the number of independent inputs needed to drive all the rigid within the mechanical system. Twelve degrees of freedom as shown by the arrows n clockwise and anticlockwise directions, all relate to a common and central axis of the work piece notable at the six degree of freedom and the six radial degrees of freedom. Straight line movements in the three principal axes X, Y and Z are allowed by the axial degrees of freedom (Ni, Huang &Wu 1992). A machine vice. This is a device used to hold a work piece during the operation of a milling machine or a drill press machine. A machine vice can be adjusted in different ways, by allowing any work piece to be manipulated into any position or angle as per the requirement. It is important when certain angle is to be repeated on several pieces. (Cook, 1995) This machine’s precision movement allows for the creation of pinpoint operations through manipulation of the vice’s controls. For the milling operations, it is useful in moving the work piece into the cutting tool and completes the machine operations, as the cutting tools remain stationary. (Fan, Chen & Huang 1998). A four jack lathe chuck. A 4-jaw lathe has the advantages of high precision in centering work. It can handle square or rectangular bars perfectly as compared to a 3jaw jack lathe chuck. It can also turn work off center, with relatively more grips on the round stocks. Despite all this, the 4 jaw jack lathe has limitations in lack of self-centering inconveniences as those of the three jaw chuck. A four jaw lathe chuck has grooves in the body chuck face in order to make centering of the work easier (Cook et al 1995). (Cook, 1995)a four jaw lathe chuck. Methods for securely locating cutting tools in a center lathe and vertical milling machine. For the purposes of enhanced performance, work holders have to be accurately positioned and consistently located. Any work piece relative to the cutting tool should be properly referenced (work piece positions relative to work holders) and the whole process is repeated. There exists three forms of location, concentric, plane and radial. The characteristics of each are the plane locator’s method of locating a piece of work from Whatever surface; concentric locators mainly locate a work piece from a central axis while radial locators restrict movements of any work piece around the concentric locator. In addition, it is important to note that locating created from both the internal and external surfaces (Cook, 1995) A center lathe. In ordinary turning, the cutting tool moves along a parallel line to the axis of the work to finish an equal diameter dimension on a piece of work. Features that create efficiency in the moving such as enhance the movement: A larger screw: this causes the lathe cutter to advance greater lengths (quickly) used to cut screws at feed rates ranging from 0.05” to 0.5” per revolution. A smaller screw: it moves the cutter shorter lengths (slowly). It is largely applicable when performing rough cuts or finishing operations of 0.001” to 0.010” feeds per revolution. A vertical milling machine. The process of milling on a vertical mill is in most instances accomplished by end mills. Cutters used with this machine designed to cut with both ends. Through raising and lowering the entire milling head with the “Z” axis feed screw, the drilling process is successfully accomplished. Center drills are incorporated prior to drilling to set the required degree of accuracy. Boring, a method of making accurate holes through rotating a tool with a single cutting edge (boring head), is meant to open up a drilled holes to the desired dimensions in diameter. Cutting actions of milling cutters vary depending on the direction of feed. In one direction, the tools tend to climb onto the works while in other cases the tool will tend to move away from the cut. Bibliography. Cook, J. T., & Mason, F. (1995). Milling and machining center basics. [Dearborn, Mich.], Society of Manufacturing Engineers. Devore, C., Roberts, J., & Saunders, T. (1979). Milling and tool sharpening. Virginia Beach, VA, Coastal Video Communications Corp Mansfield, E. (1977). The Production and application of new industrial technology. New York, Norton. Weck, M. (1984). Handbook of machine tools. Chichester [West Sussex], Wiley. Read More