Technology Lect Machining Part 1 Lec 5 PDF

Production Technology Introduction to Machining Operations Associate Prof. Mohamed A. Bhlol  Topics Machining technology definition Importance and advantages of machining Machining operations: - Turning operations - Milling operations - Drilling operations - Shaping operations...

Production Technology Introduction to Machining Operations Associate Prof. Mohamed A. Bhlol  Topics Machining technology definition Importance and advantages of machining Machining operations: - Turning operations - Milling operations - Drilling operations - Shaping operations  Machining technology definition Machining operation is a material removal process in which a sharp cutting tool is used to mechanically cut away material so that the excess metal is removed in form of deposal chip and the desired part geometry generated. Tool Chip WP  Machining technology definition Types of Machined Parts a) Rotational - cylindrical or disk‑like shape b) Nonrotational (also called prismatic) -block ‑like or plate‑like  Importance and advantages of machining Importance/Advantages of machining Removing undesired materials remaining from other production methods for example casting, forging etc. … It is important in industry to produce components with tight tolerance and high accuracies and with high surface quality.  Importance and advantages of machining Disadvantages of machining Lose a lot of materials, Need skillful person, and Need large investment (Machine price)  Turning process Turning Single point cutting tool removes material from a rotating workpiece to generate a cylinder. Performed on a machine tool called a lathe  Turning process Single point cutting tools Solid tools Brazed tools Insert bit tool  Motions in machining process  The cutting process is achieved in most machining operations by means of a primary motion, and secondary motion  Primary (Main) motion: is the main cutting motion responsible of metal cutting. it is measured by the cutting speed  Secondary (Feed) motion: is the motion responsible of expanding the cutting motion to whole required surface. It is measured by the cutting feed  Adjustment (Depth) : is the motion responsible of the interference between tool and wp. It is measured by the depth of cut Motions in turning process n io ot m n ai M Feed motio n g it n j us Ad  Cutting parameters Turning Turning Parameters Speed (v) Feed (S or f) Depth of cut (t or a)  Turning operations Engine lathe  Turning operations Turning Operations Turning operations Adjusting center  Turning operations Longitudinal turning Turning operations Face turning  Turning operations Center drilling and drilling Turning operations Taper turning  Turning operations Knurling  Methods of holding workpiece in a lathe a) Holding the work between centers b) Chuck c) Collet d) Face plate Methods of holding workpiece in a lathe  Milling process Milling is a machining operation in which work is fed past a rotating tool with multiple cutting edges Cutting tool called a milling cutter, cutting edges called "teeth“ Machine tool called a milling machine  Milling process Multi-point cutting tools (Milling cutters)  Milling process Two Forms of Milling 1) Peripheral milling – Cutter axis parallel to surface being machined – Cutting edges on outside periphery of cutter 2) Face milling – Cutter axis perpendicular to surface being milled – Cutting edges on both the end and outside periphery of the cutter  Milling process Milling machines Horizontal Milling Machine Vertical Milling Machine  Motions in milling process Motions and cutting prameters Milling Parameters Speed (v) Feed (S) Depth of cut (t) Milling operations  Drilling process Drilling is a machining operation which creates a round hole in a workpart Cutting tool called a drill or twist drill Machine tool: drilling machine  Drilling process Twist drill  Drilling process Drilling machines Bench drill Up-right drill Radial arm drill  Motions in drilling process Motions and cutting parameters Drilling Parameters Speed (v) Feed (S) Depth of cut (t) Drilling operations Drilling  Drilling operations  Drilling : Operation of producing a cylindrical hole in a solid body by means of a drill.  Reaming : Operation of finishing the drilled hole (that is achieving the closer tolerances and desired surface finish) by means of a reamer.  Boring : A drilled hole can be enlarged also by means of boring tool on the drill machine.  Counter Boring : Enlarging the diameter of the drilled hole only upto certain depth. For this counter boring tool is used.  Counter Sinking : It is enlarging the top end of a drilled hole and giving it a conical shape by the help of a counter sinking tool.  Spot Facing : Squaring the surface at the top end of a hole to provide a true seat for the bolt head or collar.  Tapping : A tap can be rotated inside an already drilled hole to produce internal threads.  Shaping process Shaping operation is used for producing relatively small flat surfaces. A single point tool is mounted on a tool box fitted to a reciprocating ram. The job is clamped in a vice. There is a cutting action in the forward motion of the tool while the return stroke is idle. Shaping process Shaper and planner machines Shaper machine Planner machine  Shaping operations Facing of Facing of Machining vertical of rack horizontal surface surface  Motions in shaping operation Motions and cutting parameters Shaping Parameters Speed (v) Feed (S) Depth of cut (t)  CNC machines CNC:Computerised Numerical Control (Computer + Numerical Control) Numerical control is a programmable automation in which process is controlled by Numbers, Letters, and symbols. CNC Machining is a process used in the manufacturing sector CNC turning machine that involves the use of computers to control machine tools like lathes, mills and grinders Thank you