Lathe Machine Lab free essay sample

Beside that ,it can be used to measure the length of the object, which specific size is 100mm and 25mm in diameter. 3. 2) Lathe Machine A lathe is a machine tool which rotates the workpiece on its axis to perform various operations such as cutting, sanding, knurling, drilling, or deformation with tools that are applied to the workpiece to create an object which has symmetry about an axis of rotation. Lathes are used in woodturning, metalworking, metal spinning, and glassworking. Lathes can be used to shape pottery, the best-known design being the potters wheel. Most suitably equipped metalworking lathes can also be used to produce most solids of revolution, plane surfaces and screw threads or helices. Ornamental lathes can produce three-dimensional solids of incredible complexity. The material can be held in place by either one or two centers, at least one of which can be moved horizontally to accommodate varying material lengths. Other workholding methods include clamping the work about the axis of rotation using a chuck or collet, or to a faceplate, using clamps or dogs. Group 3 | Weekly Report | Lathe P a g e |1 WEEKLY REPORT – LATHE MANUFACTURING LAB (MEFB 121) GROUP 3 REV NO : 000 DATE : 11 NOVEMBER 2011 Below are the list of parts and functions in lathe machine. No 1 Components Bed Functions Provides a heavy rigid frame on which all the main components are mounted. Inner and outer guide rails that are precision machined parallel to assure accuracy of movement. mounted in a fixed position on the inner ways, usually at the left end. Using a chuck, it rotates the work. inside the headstock, providing multiple speeds with a geometric ratio by moving levers. Hole through the headstock to which bar stock can be fed, which allows shafts that are up to 2 times the length between lathe centers to be worked on one end at a time to clamp part being machined and allows the mounting of difficult workpieces that are not round, square or triangular. Fits on the inner ways of the bed and can slide towards any position the headstock to fit the length of the work piece. An optional taper turning attachment would be mounted to it. Moves on the outer ways. Used for mounting and moving most the cutting tools Mounted on the traverse slide of the carriage, and uses a hand wheel to feed tools into the workpiece. To mount tool holders in which the cutting bits are clamped Mounted to the cross slide, it pivots around the tool post Attached to the front of the carriage, it has the mechanism and controls for moving the carriage and cross slide. For cutting threads 2 Ways 3 Headstock 4 Gearbox 5 Spindle 6 Chuck 7 Tailstock 8 9 Carriage Cross Slide 10 11 12 Tool Post Compound Rest Apron 13 Lead Screw Group 3 | Weekly Report | Lathe P a g e |2 WEEKLY REPORT – LATHE MANUFACTURING LAB (MEFB 121) GROUP 3 REV NO : 000 DATE : 11 NOVEMBER 2011 4. PROCEDURE Procedure for this purpose can be classified into 3 different topics; Work procedure, Operation and Safety precautions which each of those carried elements of different perspective but act under the same objective. 4. 1. Work Procedure I. Morning briefing by the technician; Mr. Shamsul on all aspect of job scope II. Proper safety attire were wore first III. Our group were given one workpiece for this particular activity. Using vernier calliper, the dimensions obtained and shown as per below : 100mm O25 Figure 3 – Initial workpiece dimension IV. V. The workpiece later being lock and was placed firmly in the spindle. The cutting tool was aligned to the dead center. The machine was turned on. The carriage was moved to the left by rotating the hand wheel until the tip of the cutting tool touches the edge of the metal cylinder. Cutting tool touch the edges 0. 5mm Group 3 | Weekly Report | Lathe P a g e |3 WEEKLY REPORT – LATHE MANUFACTURING LAB (MEFB 121) GROUP 3 REV NO : 000 DATE : 11 NOVEMBER 2011 VI. VII. VIII. IX. For safety reason, the workpiece were mounted with 0. 5mm per run(safe operation). The machine then were run by cutting the whole workpiece for 20mm diamater. This process need to be done two times which one on the left hand side and the right hand side. The carriage need to be push to the left slowly. For 20mm diameter cut,we need to repeat 4 times because to follow the safe operation procedure. Step 6 below were repeated for cutting the 15mm and 10 mm diameter. The final workpiece is as per below: O10 O15 O20 Figure 4- the final workpiece. 4. 3. Operation I. II. To perform lathe activity, the workpiece need to be lock and secure in the spindle at first. Then the lever that control the x-axis of the lathe machine is adjust and set to 0. This step is essential so that the operator keep tracks of the depth between the initial and the final workpiece. For safety purporse, the lathe machine only can cut down the workpiece for 0. 5mm per run. Apart from that,coolant switch also are turned on to reduce the friction between the cutter n workpiece. After all, the main switch is turned on and the cutter start to rotate itself. The lever on the x-axis need to be move to the left and the process of lathe begin. Push the lever slowly to the end. Lathe the workpiece until the end and after the process done,turn off the machine. III. IV. V. Group 3 | Weekly Report | Lathe P a g e |4 WEEKLY REPORT – LATHE MANUFACTURING LAB (MEFB 121) GROUP 3 REV NO : 000 DATE : 11 NOVEMBER 2011 4. 2. Safety Precautions I. II. III. IV. V. VI. VII. Before setting up a job, be sure that the workpiece, the table, the taper in the spindle, and arbor or cutter shank, are all clean and free from chips, nicks, or burrs. Keep lathe cutters sharp at all times. Do not change feeds or speeds while the lathe machine is in operation. Always turn on the coolant while doing the lathe process. This will reduce the total friction between the cuters and the workpiece. Never run a the lathe machine without the workpiece. When using clamps to secure the workpieces, be sure that they are tight and that the workpiece is held so that it will not spring or vibrate while it is being cut. Keep chips away from the workpiece; brush them out of the way by any convenient means, but do not do so by hand or with waste. NEVER remove chips with your bare hands. Use a stick or brush, and always stop the machine. Should it become necessary to operate the lathe while the ship is underway, be especially safety conscious. (Machines should be operated ONLY in relatively calm seas. ) VIII. 5. DISCUSSION From the activity that we done, we can sum up on several process that related to lathe machine. Points below explain the process of the lathe machine works on the workpiece. I. Turning A right-hand turning tool bit is shaped to be used from right to left. The cutting edge is on the left side of the tool bit and the face slopes down away from the cutting edge. The left side and end of the tool bit are ground with sufficient clearance to permit the cutting edge to bear upon the work piece without the heel rubbing on the work. The right-hand turning tool bit is ideal for taking light roughing cuts as well as general all-around machining. A left-hand turning tool bit is the just like right-hand turning tool bit, except that it’s the opposite. This tool bit is designed to cut when fed from left to right. The round-nose turning tool bit is very versatile and can be used to turn in either direction for roughing and finishing cuts. No side rake angle is ground into the top face when used to cut in either direction, but a small back rake angle may be needed for chip removal. The nose radius is usually ground in the shape of a half-circle with a diameter of about 1/32 inch. The right-hand facing tool bit is intended for facing on right-hand side shoulders and the right end of a work piece. The cutting edge is on the left-hand side of the bit, and the nose is ground very sharp for machining into a square corner. The direction of feed for this tool bit should be away from the center axis of the work, not going into the center axis. A left-hand facing tool bit is the opposite of the right-hand facing tool bit and is intend to machine and face the left sides of shoulders. Example of the process as shown in figure 5. Group 3 | Weekly Report | Lathe P a g e |5 WEEKLY REPORT – LATHE MANUFACTURING LAB (MEFB 121) GROUP 3 REV NO : 000 DATE : 11 NOVEMBER 2011 Figure 5- The turning of the lathe machine cutter. II. Feed speed and depth of cut Cutting speed is defined as the speed at which the work moves with respect to the tool. Feed rate is defined as the distance the tool travels during one revolution of the part. The finish is determined by the cutting speed and feed, power requirements, and material removal rate. The primary factor in choosing feed and speed is the material to be cut. However, one should also consider material of the tool, rigidity of the work piece, size and condition of the lathe, and depth of cut. To calculate the proper spindle speed, divide the desired cutting speed by the circumference of the work. In considering depth of cut, its important to remember that for each thousandth depth of cut, the work diameter is reduced by two thousandth. Some calculation can be done to define the feed speed but there a few missing variable like the rotation per minute (RPM) of the lathe machine use. To calculate spindle speed required, N=CS(1000) ? d N= Spindle speed( RPM) CS= Cutting speed of the metal(m/mm) d=diameter of the workpiece Group 3 | Weekly Report | Lathe P a g e |6 WEEKLY REPORT – LATHE MANUFACTURING LAB (MEFB 121) GROUP 3 REV NO : 000 DATE : 11 NOVEMBER 2011 III. Industrial application The lathe is one of the engineers most valuable tools. Coupled with a milling machine or milling head (Tri-axis lathe) there is nothing that cannot be produced from virtually any kind of material. A lathe can be used to a) b) c) d) e) f) g) h) i) j) Turn an ornate wooden spindle Skim a cylinder head or other gasket-face Put a screw-thread on a piece of metal bar Drill a hole of almost any size in almost any material Machine an intricate valve, collet or gudgeon Put a screw-thread inside a hole (Tap the hole) Produce a complex component such as a cog-wheel, crown wheel or pinion Re-bore the cylinder of an engine Create irregular / offset flanged components of infinite complexity.