Comprehensive Guide to Manufacturing Processes Covering Casting, Forming, Machining and Moulding

Shubham Kola

Welcome to this all-in-one educational video that covers major manufacturing processes like Casting, Forming, Machining, and Moulding in detail. Learn with animated diagrams, real-life examples, and expert explanations designed for engineering students, competitive exams (GATE/UPSC), and industry professionals.  📌 What You'll Learn in This Video: 👉Manufacturing Process Classification 👉Working principles with animations 👉Industry applications of processes 👉Key techniques like Sand Casting, Forging, Milling, Drilling, Injection Moulding, and more  🕒 Timestamps (Chapters):  00:07 - Introduction to Manufacturing Processes 00:51 - What is a Manufacturing Process? 01:11 - Classification of Manufacturing Processes 01:26 - Overview of Casting, Forming, Machining & Moulding  02:24 - Casting Processes 02:29 - Gating System in Casting (Pattern, Sprue, Runner, Cope, Drag, etc.) 05:14 - Types of Patterns & Mold Cavity 10:50 - Moulding Methods (Bench Moulding, Floor Moulding, Green Sand Moulding, etc.) 13:36 - Core, Types of Cores, Core Prints & Chaplets 15:18 - Cupola Furnace – Construction & Working 18:52 - Electric Arc Furnace – Construction & Working 20:54 - Centrifugal Casting Process 22:01 - Investment Casting Process 23:21 - Shell Moulding Process 25:10 - Hot Chamber Die Casting Process 26:24 - Cold Chamber Die Casting Process  26:53 - Metal Forming Processes 27:02 - Forging Processes (Open Die Forging, Closed Die Forging, Press Forging Process, etc.) 29:25 - Extrusion Process (Direct Extrusion, Indirect Extrusion, Hot Extrusion, etc.) 31:57 - Rolling Process (Hot Rolling Process and Cold Rolling Process) 33:52 - Press Working Operations (Punching or Piercing, Blanking, Notching and Lancing) 34:58 - Press Working Operations (Slitting, Trimming and Shaving) 35:49 - Press Working Operations (Bending and Drawing)  36:19 - Machining Processes 36:23 - Nomenclature of Single Point Cutting Tool 39:23 - All Lathe Machine Operations (Turning, Boring, Facing, Chamfering, etc.) 47:12 - Drilling Machine Types and Nomenclature of Twist Drill Tool 52:01 - Drilling Operations (Reaming, Tapping, Boring, Spot Facing, etc.) 54:30 - Milling Machines (Column and Knee type Milling Machine, Plano Miller) 58:44 - Horizontal Broaching Machine and Nomenclature of Broaching Tool 01:01:07 - Grinding and Centerless Grinding Process  01:02:23 - Moulding Processes 01:02:27 - Plastic Injection Moulding Machine 01:04:03 - Plastic Moulding Processes (Compression Moulding, Blow Moulding, etc.) 01:04:15 - Compression Moulding Method 01:04:41 - Blow Moulding Method 01:05:07 - Extrusion Moulding Method 01:05:44 - Vacuum Forming Method 01:06:44 - Calendaring Process  Faculty - Shubham Rukman Kola Email ID - shubhamkolaofficial@gmail.com From - Maharashtra ( India ) YouTube Channel ( Shubham Kola ) - https://www.youtube.com/channel/UCZKJoXyqcOOKzFOqdMt9yAg

Transcript

00:00:00Hello students, my name is Shubham Rukman Kola.

00:00:10I am a BE mechanical engineer.

00:00:12Welcome to this lecture on the complete guide to manufacturing processes.

00:00:18In this video, we will explore all major manufacturing processes covering casting, forming, machining

00:00:25and moulding techniques in detail.

00:00:29You will learn their working principles, applications and real-world uses through animations and

00:00:35explanations.

00:00:38By the end of this lesson, you will have clear understanding of how different materials are

00:00:42processed and shaped into finished products.

00:00:45Now, let's begin our journey into the world of manufacturing processes.

00:00:51So first we'll discuss, what is manufacturing process?

00:00:56A manufacturing process is a step-by-step method used to convert raw materials into finished

00:01:01products.

00:01:04These processes ensure efficiency, precision and large-scale production.

00:01:12Manufacturing processes are broadly classified into four main types.

00:01:17First is casting processes, second is forming processes, third is machining processes and

00:01:23fourth one is moulding processes.

00:01:26In casting processes, the moulded metal is poured into the mould and solidifies into a specific

00:01:32shape.

00:01:33This is widely used for producing engine parts, pipes and machine components.

00:01:40Next is forming processes.

00:01:42In forming processes, the material is reshaped without cutting or removing any part.

00:01:50Processes like rolling, forging and extrusion fall under this category.

00:01:56Next is machining processes.

00:01:58The machining processes involves cutting and shaping materials using tools like lathes, milling

00:02:05machine and grinders to create precise components.

00:02:10Next is moulding processes.

00:02:12In moulding processes, there are various techniques like injection moulding, blow moulding and vacuum

00:02:18forming are used to shape plastic and other materials into desired forms.

00:02:25In casting processes, we will see the following points.

00:02:30So first is gating system.

00:02:32So here gating system consists of flask made up of wood which holds sand mould.

00:02:38Here drag is the lower moulding flask and cope is the upper moulding flask.

00:02:41Here parting line is the dividing line between two moulding flasks.

00:02:45And pattern is the replica of a final object to be made with some modifications.

00:02:49And mould cavity is made with the help of pattern.

00:02:52Here moulding sand is a freshly prepared refractive material.

00:02:56It is the mixture of silica, clay and moisture.

00:02:59Here fishing sand is a small amount of carbonaceous material sprinkled on inner surface of mould

00:03:04cavity to give better surface finish to casting.

00:03:08Here cope is used for making hollow cavities in casting.

00:03:11Pouring basin is a funnel shaped cavity on the top of mould into which molten metal is poured.

00:03:17Pouring is the passage from pouring basin to mould cavity.

00:03:20It controls flow of molten metal into mould.

00:03:23Here runner is the passageways through which molten metal flow is regulated before they reach

00:03:28the mould cavity.

00:03:29Here gate is the actual entry point through which molten metal enters the mould cavity.

00:03:34Here chill is the metallic object to increase cooling rate of casting.

00:03:38Here riser is the reservoir of molten metal so that hot metal can flow back into mould cavity

00:03:43when there is reduction in volume of metal due to solidification.

00:03:48In sand mould making procedure.

00:03:50The first step in making mould is to place pattern on moulding board.

00:03:54The drag is placed on board.

00:03:56Here dry facing sand is sprinkled over board to provide non sticky layer.

00:04:01Moulding sand is then riddled in to cover pattern with fingers.

00:04:05When drag is completely filled, the sand is then firmly packed in drag by means of hand

00:04:09rammer.

00:04:10The ramming must be proper.

00:04:11After the ramming is over, the excess sand is levelled off with straight bar known as

00:04:16strike rod.

00:04:18With the help of vaint rod, vaint holes are made in drag to full depth of flask.

00:04:23The finished drag flask is now rolled over to bottom board exposing the pattern.

00:04:28Cope half of pattern is then placed over drag pattern with the help of locating pins.

00:04:33The cope flask on drag is located aligning again with the help of pins.

00:04:38The dry parting sand is sprinkled all over the drag and on pattern.

00:04:42Here sprue pin is located at a small distance from pattern.

00:04:45The operation of filling, ramming and venting of cope proceed in same manner as performed

00:04:50in drag.

00:04:51The sprue and riser pins are removed first and pouring basin is scooped out at the top to

00:04:56pour liquid metal.

00:04:58The pattern from cope and drag is removed and facing sand in form of paste is applied

00:05:03all over the mould cavity, which gives finished casting with good surface finish.

00:05:09The mould is now assembled and mould is ready for pouring.

00:05:13Now, next we will see pattern types and mould cavity.

00:05:21So first is single piece pattern, which is the simplest type of pattern used for simple

00:05:25object which is made in single piece.

00:05:28It is either placed in cope or in drag according to simplicity of operation.

00:05:33This type of pattern used to cast stuffing box of steam engines.

00:05:37The next type is two-piece pattern or also called as split pattern.

00:05:44In this type of pattern, the half part is always moulded in drag and other half part is moulded

00:05:49in cope.

00:05:51The cope part of pattern has dual pins.

00:05:53These dual pins are used to align two halves of two-piece pattern.

00:05:58Holes in drag half match exactly with dual pins.

00:06:01This type of pattern widely used in steam walls.

00:06:07Multi-piece pattern is used when casting have very difficult and complicated design.

00:06:12In this type, three or more pieces consist of top, bottom and middle parts.

00:06:18The bottom part is drag, top part is scope, where the middle part term as check box.

00:06:23This type of pattern is used in various kinds of joints such as metri joint, dual joint.

00:06:32A cope and drag pattern is a split pattern having cope and drag portions and each mounted

00:06:37on separate match plates.

00:06:39These two separate parts are combined to form the entire cavity.

00:06:43Cope and drag pattern is almost like two-piece pattern.

00:06:46This pattern type is used in production of large casting, where moulds are heavy and unhandy

00:06:52for the users.

00:06:53This type of pattern is used in building flank pipes.

00:06:57The cope and drag pattern is also used in water jackets, which is important component of JCB.

00:07:06Match plate pattern is a split pattern in which cope and drag section mounted on opposite sides

00:07:11of plate.

00:07:12Here the plate is known as match plate.

00:07:15This will make easy to cast any shape with high production rate.

00:07:19These patterns are used for mass production.

00:07:21The match plate pattern are used to cast piston rings of IC engine.

00:07:29The loose piece pattern is used when removal of pattern is impossible due to extend surface

00:07:35at either upper half or lower half.

00:07:37The extended part made as loose piece, so this extended part can be removed first before

00:07:42removal of whole pattern.

00:07:44This will make easy removal of pattern without effect on cavity.

00:07:48It is used in production of axle pin, also used to cast rotor hub.

00:07:57Next is gated pattern.

00:07:59These are used to make multiple components inside the single mould.

00:08:03Gated pattern is nothing but the pattern consists of one or more pattern.

00:08:07Here gates are used for joining different patterns.

00:08:11These are loose patterns where gates and runners have already attached.

00:08:15These patterns are very expensive.

00:08:16Due to their high cost, they are used for creating small casting.

00:08:21These small casting further used in moulding machine as well as in mass producing processes.

00:08:27This type of pattern is implemented in small castings such as corner bucket.

00:08:35In sweep pattern, the sweep is a section or board of proper contour that is rotated about

00:08:41to an edge to shape mould cavities having shapes of rotational symmetry.

00:08:46This type of pattern is used when casting of large size is to be produced in short time.

00:08:52This pattern used to cast circular disc and wheels are produced by making use of sweep pattern.

00:09:01Skeleton pattern used for large simple casting.

00:09:04Here skeleton like structure is made by using simple pattern section.

00:09:09This will save time and material.

00:09:11It is just like sweep pattern.

00:09:13These are simple wooden frames that outline shape of part to be cast and are also used as

00:09:18guide by molder in hand shaping of mold.

00:09:22This type of pattern also used in pit or floor molding.

00:09:26The skeleton pattern used in turbine manufacturing.

00:09:29Also used in daily application such as water pipes.

00:09:36Follow board pattern consists of tool that is simple wooden board which is used for several reasons.

00:09:42The wooden board is used as a base for molding process.

00:09:46This type of pattern is used for casting master pattern for many purposes.

00:09:55Segmental pattern is just similar to sweep pattern.

00:09:58The working structure of segmental pattern and sweep pattern is almost similar.

00:10:03For designing required shape or structure of mold, they both employ a part of pattern.

00:10:08As the name suggests, segmental pattern is in form of segments and are used for molding,

00:10:14circular or round structures.

00:10:16In sweep pattern, there is complete rotation.

00:10:19But in segmental pattern, there is no complete rotation.

00:10:22And for creating mold, we can rotate partly to get required output.

00:10:27The segmental pattern is used for constructing circular structures like wheels, rims and pulleys.

00:10:38Shell pattern is used for obtaining hollow shaped structure.

00:10:41Along the center, parting process is done.

00:10:44And here resulting helps produces after parting our board weld.

00:10:51Now, next we will see, molding processes and types of molding sands used for molding processes.

00:10:58So, molding processes are classified according to type of method used and what type of mold material used in molding process.

00:11:04So, there are four types of molding methods.

00:11:07Those are bench molding, floor molding, pit molding and machine molding.

00:11:12And according to mold material, four types of molding process are green sand molding, dry sand molding, loam sand molding and coarse sand molding process.

00:11:21So, in first category, bench molding method is done on workbench of a height convenient to molder.

00:11:27This molding method is best suited to prepare mold of small and light atoms which are to be casted by non-ferrous metals.

00:11:35Where in floor molding method, we make sand casting on a ground or on floor by sand box.

00:11:41The floor molding method uses silica sand as a molding material, which is low cost, easy mold manufacturing, suitable for small production and mass production.

00:11:49Pit molding method used for large casting work.

00:11:53Here pit means large holes in ground act as a lower flask, called as drag.

00:11:58Here walls of pits are brick lined and plastered with loam sand and allowed to dry.

00:12:04Machine molding method is employed for high production rate, casting of large and medium sized molds.

00:12:09This method is used for producing better quality of molds.

00:12:13Now in second category, green sand molding, where green sand consists of silica sand, 10-15% clay and 4-6% moisture content.

00:12:22And all these materials are thoroughly mixed and riddled.

00:12:25It should also be given the required condition by proper tempering.

00:12:29Dry sand molding is just similar to green sand molding process.

00:12:33Drying sand gives strength to mold so that it can be used for large casting such as part of engine, large size of flywheel, rolls of rolling wheel.

00:12:42This process is costlier than green sand molding but much superior in quality.

00:12:47Loam sand molding process is used for extremely large size of casting which are to be made in small numbers.

00:12:53Loam sand molds are prepared with coarse-grained silica sand, clay, coke, hose manure and water.

00:12:59This process of molding is performed in different ways.

00:13:02Here firstly, a rough structure of desired shape is made by hand by using brick and loam sand.

00:13:08This structure is then finished by means of strickle and sweep.

00:13:12Here the surface of structure are blackened and dried before being casted.

00:13:17For coarse sand molding process, here sand which contain more than 5% clay may not be used as a coarse sand.

00:13:24For coarse making by hand, coarse sand is filled and rammed in coarse box.

00:13:28The whole operation takes short time.

00:13:30After that, coarse box is withdrawn and coarse is removed.

00:13:33Now, next we will see the core, types of cores, core prints and chaplets in casting process.

00:13:46So, core is a device that is inserted into mold to produce internal cavities such as holes or passage.

00:13:52So, generally, cores are of two types, green sand core and dry sand core.

00:13:57Here, green sand core is made out of the same sand from which rest of mold has been made,

00:14:02where dry sand core is prepared separately in core boxes.

00:14:06These types of cores are also known as process cores.

00:14:09They are available in different sizes and shapes.

00:14:11Some common types of dry sand cores are horizontal core, vertical core, balanced core, hanging core, drop core and kiss core.

00:14:19So, here, horizontal core is positioned horizontally at the parting surface of mold.

00:14:24The ends of core rest in seats provided by core prints on pattern.

00:14:29Now, here, core prints are the races to the pattern.

00:14:32This will add projection on pattern and it forms seat in mold on which sand core is rest.

00:14:38Here, core prints have to be of sufficient size and shape so that it can hold weight of core in casting process.

00:14:44The vertical core is pressed vertically with some of their portion lies in sand.

00:14:50The balanced core extends on one side of the mold.

00:14:53Only one core print is available on pattern for balanced core.

00:14:57This is best suitable for the casting, has only one side opening.

00:15:01This is used for producing blind holes or ashes in the casting product.

00:15:05The hanging core is suspended vertically in the mold.

00:15:08This is achieved either by hanging wires or the collar core rest in the collar cavity created in upper part of mold.

00:15:15This type of cores does not have bottom support.

00:15:18The drop core is used when the core has to be placed either above or below the parting line.

00:15:23This core is also known as wire core, tail core or chair core.

00:15:28The key score is used when number of holes of less dimensional accuracy is required.

00:15:33In this case, no core prints are provided and no seat is available for core.

00:15:38The core is held in position approximately between the cope and rack and hence referred as key score.

00:15:44In casting process, the chaplet is a small metal insert or spacer used in molds to provide core support during casting process.

00:15:52Here, core prints are added to both sides of pattern to create chaplets.

00:15:57Now, next point we will discuss, the working of cupola furnace and electric arc furnace in casting process.

00:16:08Construction and working of cupola furnace, so it is a melting device used to melt cast iron.

00:16:14The outermost part of cupola furnace is a cylindrical steel shell and equipments are fitted vertically inside this cylindrical shell with doors.

00:16:22The top side of cupola furnace is fitted with cap to prevent excess of harmful gases to envorm it.

00:16:28The cupola shell is made up of steel and has lining of refractory bricks.

00:16:32This furnace is supported on cast iron legs mounted on concrete base.

00:16:37Near bottom part, it has sand bed, above which melted iron flow.

00:16:42This sand bed is tapered.

00:16:43Near elevated side of tapered sand bed, slag hole is present through which slag formed from impurities.

00:16:49Near downside of down bed, tap hole is present through which molten iron comes out.

00:16:55Above the sand bed, air reaches the furnace and helps in combustion.

00:17:00Near the top of furnace, metal, coke and limestone are feed into furnace through charging door.

00:17:06During working of cupola furnace, wood is ignited above the sand bed.

00:17:11When the wood starts burning properly, coke is dumped on the well from top.

00:17:16The combustion starts in coke bed using fire from burning wood and using air from tires.

00:17:22At this time, the air blast is turned out at lower blowing rate than normal.

00:17:27After nearly 3 hours of burning, alternate layers of limestone, pig iron and coke is charged until it reaches the level of charging door.

00:17:35At this time, the air blast is turned on to normal blowing rate and combustion occurs more rapidly in coke bed.

00:17:43All oxygen from air blast is consumed by combustion and in combustion zone, the temperature varies from 1150 to 1850 degree Celsius.

00:17:52The portion of coke bed above the combustion zone is reducing zone.

00:17:56This zone prevents oxidation of metal charge.

00:17:59As the carbon dioxide moves through this zone, some of it reduces by following reaction.

00:18:05The layer of iron above reducing zone is melting zone where solid iron is converted into molten iron.

00:18:12Above the melting zone, there is preheating zone where charge is preheated by outgoing gases.

00:18:18Within 5 to 10 minutes of starting air blast to normal blowing rate, the first molten iron appears at the tap hole.

00:18:25The charging door is closed till the metal melts.

00:18:28The content of charge moves down as melting proceeds.

00:18:31When the melting process is finished and no more molten iron is required, the feed of charge is stopped and air blast is also stopped.

00:18:39The bottom plate is swing to open when probe is removed and slag is removed.

00:18:44Normally, couple of furnace is not used more than 4 hours but can be used for 10 hours of continuous operation.

00:18:50Construction and working of electric arc furnace.

00:18:56The electric arc furnace is a steel making furnace in which steel scrap is heated and melted by heat of electric arcs striking between furnace electrode and metal bath.

00:19:06The electric furnace is used to produce mini steel structural bars and steel rods.

00:19:11The main parts of electric arc furnace are the electrodes, roof, earth and sidewalls.

00:19:17The roof consists of 3 holes through which electrodes are inserted.

00:19:20The earth includes metal and slag.

00:19:23The tilting mechanism is used to pour metal that is molten to cradle by shifting furnace.

00:19:29In AC electric furnace, the electrodes are 3 in number.

00:19:32These are round in section.

00:19:34Here, graphite is used as an electrode because of high electric conductivity.

00:19:38The electrodes get highly oxidized when current density is high.

00:19:42The transformer provides electrical supply to electrodes.

00:19:46The working of electric arc furnace include charging the electrode, melting the metal and refining process.

00:19:52Here, heavy and light scrap in large basket is preheated with the help of exhaust gas.

00:19:58The charging of furnace takes place by swinging roof of furnace.

00:20:02During the period of melting the metal, the electrodes are moved down onto the scrap.

00:20:07Then arc is produced between electrode and metal.

00:20:10After arc is shielded by electrodes, the voltage is increased for speeding up melting process.

00:20:16In this process, carbon silicon and manganese get oxidized.

00:20:20Here, lower current is required for large arc production.

00:20:23The refining process starts during melting.

00:20:26There are mainly two types of electric furnace.

00:20:29In DC arc furnace, current flows from cathode to anode.

00:20:33This furnace has only single graphite electrode.

00:20:36An other electrode is embedded at the bottom of furnace.

00:20:40In AC electric arc furnace, current flows between electrodes through the charge in metal.

00:20:45In this furnace, 3 graphite electrodes are used as a cathode.

00:20:49The scrap itself acts as an anode.

00:20:54Now, next point we will discuss.

00:20:56The centrifugal casting process.

00:21:01Centrifugal casting process which is used to cast components of high material roundness.

00:21:06This casting technology used for application like jet engine compressor case, hydro wearings,

00:21:11many military products and other high reliability applications.

00:21:16The centrifugal casting process begins with molten metal being poured into pyrite spinning dye.

00:21:22The dye may be oriented either on vertical or horizontal axis depending on configuration of desired part.

00:21:29By spinning mold while the molten metal is poured into it,

00:21:32centrifugal force acts to distribute molten metal in the mold at pressure approaching 100 times the force of gravity.

00:21:40As the dye begins to fill, the dense molten metal is forced to wall off spinning dye.

00:21:45Once the casting has solidified, the part is removed from dye and residual impurities are machine away,

00:21:51resulting in defectory structure without cavities or gas pockets.

00:21:55There are two types of centrifugal casting process, vertical and horizontal.

00:22:00Now, next point we will discuss.

00:22:03The working of investment casting process.

00:22:06It is also known as lost wax casting process.

00:22:10This process is used to produce precise components.

00:22:13Here the figure shows investment casting process which can be summarized in following steps.

00:22:19This casting process starts with production of wax patterns.

00:22:23Here metallic dyes are used to prepare wax patterns.

00:22:26An assembly of large number of wax patterns are made and attached to wax sprue centrally.

00:22:32Then the pattern is immersed in refractory slurry which completely surrounds it.

00:22:37This will cover or invest the assembly of wax pattern with the refractory slurry which builds the shell and set this to room temperature to form the mold.

00:22:47Now, the mold is further heated so that the wax pattern melts and flows out, leaving the required cavity behind.

00:22:54After the heating process, the mold gets further hardened and molten metal is whored.

00:23:00Once the metal casting solidifies within the mold, the metal casting is removed by breaking the refractory mold.

00:23:07And gates and runners are cut from metal casting and machining is performed to finish this metal casting dimensionally

00:23:15to get desired dimensional torrents and surface finish.

00:23:18Now, next point we will discuss.

00:23:22The working of shell molding process.

00:23:26So, it is a casting process in which the mold is thin shell made up of sand and which is held together by thermosetting resin binder.

00:23:35Here the process consists of following steps.

00:23:37The first step is to create pattern.

00:23:39And here pattern is composed of two pieces which are created in shape of desired part.

00:23:45The next step is to create mold.

00:23:47During creating the mold, each pattern half is heated to 175 to 370 degree Celsius and coated with lubricant to facilitate removal.

00:23:57Heated pattern is clamped to dump box which contain mixture of sand and resin blender.

00:24:02The dump box is inverted allowing this sand-resin mixture to coat the pattern.

00:24:07The heated pattern partially cures the mixture which now forms a shell around the pattern.

00:24:13Each pattern half and surrounding shell is cured to completion in oven and then shell is ejected from the pattern.

00:24:20The next step is to assemble the shell mold.

00:24:24Here two shell are joined together and securely clamped to form the complete shell mold.

00:24:29The shell mold is then placed in flask and supported by baking material.

00:24:34The next step is to pour the molten metal.

00:24:37During this step, the mold is securely clamped together and molten metal fills the mold cavity.

00:24:43After mold has been filled, the molten metal is allowed to cool and solidify into the shape of final castling.

00:24:50After molten metal has cooled, the mold can be broken and castling removed.

00:24:54Here trimming and cleaning processes are required to remove any excess material.

00:24:59In shell molding process, the thickness of shell can be determined accurately by controlling the time that the pattern is in contact with mold.

00:25:10Now, next point we will discuss.

00:25:12The hot chamber die casting process and cold chamber die casting process.

00:25:19The hot chamber die casting is a type of die casting that uses alloys with low melting temperatures such as zinc, lead and magnesium alloys.

00:25:28Here fixed die half called as cover die which is mounted to stationary platen and aligns with nozzle.

00:25:35The movable die half is the ejector die which slide along the tie bars.

00:25:40Here metal is contained in open pot which is placed in furnace and melted to desired temperature.

00:25:47And when plunger is in up position, then molten metal flows into the short chamber.

00:25:52As the plunger moves down, it forces the molten metal into the die.

00:25:56The machine pushes the moving platen towards the fixed die half and holds it closed with pressure until the molten metal is injected.

00:26:05Now, the plunger remains in the down position to hold the pressure while casting cools off.

00:26:10After solidification, the plunger is retracted and cast part ejected and push off the fixed die half.

00:26:16This ejection system includes ejector die and ejector pins which allows casting to be pushed out.

00:26:24Cold chamber die casting is a type of die casting that is used for alloys with high melting temperatures such as aluminum, brass and copper alloys.

00:26:32Here molten metal is ladle from the furnace into the short chamber.

00:26:37Plunger forces the metal through short chamber into the die and plunger holds the pressure and retracts after solidification.

00:26:45Here fixed die half does not have nozzle and therefore it aligns directly from the short chamber.

00:26:50Now, the next part is forming processes.

00:26:57In forming process, first point is forging processes.

00:27:02So, first we will discuss the types of forging processes.

00:27:06That is open die forging, closed die forging, press forging and drop forging process.

00:27:11In open die forging method, the workpiece is compressed between two flat dies, where in closed die forging method, workpiece is compressed between two impressed dies.

00:27:23During open die forging process, there is poor utilization of material, but in closed die forging process, there is better utilization of material.

00:27:32After open die forging process, machining of components are required, where in closed die forging process, machining of components are not required.

00:27:39are not required. The dimensional accuracy of obtained product in open die forging process

00:27:44is not good, where in closed die forging process, dimensional accuracy of obtained product is good.

00:27:50Open die forging process is suitable only for production of simple components,

00:27:54where closed die forging process is suitable for production of simple as well as complex components.

00:28:00For low quantity production, open die forging process is used and for high quantity production,

00:28:05closed die forging process is used. The cost of dies in open die forging process

00:28:10is low compared to cost of dies in closed die forging process.

00:28:14Open die forging process is simple as compared to closed die forging process.

00:28:19The next process is press forging and drop forging process.

00:28:23In press forging process, metal is shaped by means of single and continuous stroke.

00:28:28Here pressure applied is low, steady and continuous in single switching action.

00:28:32Where in drop forging process, metal is shaped by means of series of blows.

00:28:36Here pressure applied is impact and in multistroke.

00:28:40The press forging process is faster process and has higher production rate.

00:28:44Where drop forging process is relatively slow process and has moderate production rate.

00:28:49The initial cost of press forging process is higher than drop forging process.

00:28:53In press forging process, the deformation obtained is uniform, simultaneous and deep penetrating

00:28:59as center of metal part. Where in drop forging process, the deformation of metal is more

00:29:04at surface layer than that of center of metal part.

00:29:08In press forging process, shapes form are dense and homogeneous in structure.

00:29:13Where in drop forging process, shapes form are coarse and not homogeneous in structure.

00:29:18In press forging process, the quality of product is good compared to drop forging process.

00:29:23Next, we will discuss direct and indirect extrusion process and hot extrusion process and cold extrusion

00:29:31process.

00:29:34Here extrusion is a metal forming process involving shaping metal billet by forcing it through a die

00:29:40with opening. Here metal billet is a raw material placed into a container of a extrusion press.

00:29:45Here die with opening is mounted at end of container. When hydraulic driven ramp presses billet,

00:29:51the metal starts to flow through an opening forming extruded product of required cross-section.

00:29:56In direct extrusion process, the extruded metal flows in direction of a ram motion.

00:30:01In indirect extrusion process, the metal flows in direction opposite to ram motion.

00:30:06Indirect extrusion process requires lower force than direct extrusion process as there is no friction

00:30:11between billet and inside wall of a container. Direct extrusion process also known as forward extrusion

00:30:17extrusion process. The material wastage is more in direct extrusion process than indirect process.

00:30:26In direct extrusion process, the force required to release the billet out of extruder is more.

00:30:31Where in indirect extrusion process, force required is less. In direct extrusion process, the frictional

00:30:36force is high due to the fact that metal billet must travel entire length of container.

00:30:42Next, we will discuss hot extrusion process and cold extrusion process.

00:30:49Here, hot extrusion is a metal forming process of shaping metal billet by forcing it through a

00:30:53die opening. This process takes place above recrystallization temperature. Due to this

00:30:58temperature, the hydraulic driven ramp easily presses metal billet and metals start to flow through an

00:31:04opening forming extruded product of required cross-section. Where in case of cold extrusion process,

00:31:09the temperature is set to below crystallization temperature or room temperature because the

00:31:13advantage of this is high strength of extruded product due to cold working and it gives closer

00:31:18tolerance and better surface finish. In hot extrusion process, force required to press metal billet is

00:31:24low compared to cold extrusion process because metal is at melting temperature. Hot extrusion product is

00:31:30free from strain hardening, but here surface finish is low due to scale formation on finished product.

00:31:36Hot extrusion process requires high maintenance. In cold extrusion process, there is high mechanical

00:31:41properties of extruded product. Also, product has high surface finish and there is no oxidation at

00:31:46surface of extruded product. In cold extrusion process, the force required to press metal billet is high

00:31:51and here extruded product is accomplished with strain hardening.

00:31:54Next, we will discuss the hot rolling and cold rolling process.

00:32:03In hot rolling process, metal is passing through two rolls rotating in opposite direction at uniform

00:32:09peripheral speed. In hot rolling process, temperature is kept at above recrystallization temperature.

00:32:15In this process, the space between rolls is adjusted and is always less than thickness of

00:32:20metal is being fed. When metal passes through rolls, there is change in its grain structure.

00:32:25Here recrystallization temperature prevents metal from work hardening and due to this hot roll

00:32:31metal does not show work hardening effect. Due to swizzing action, the grains are elongated in direction

00:32:36of rolling and velocity of material at exit is higher than that at entry. In cold rolling process,

00:32:42the metal is fed into rolls when its temperature is below recrystallization temperature.

00:32:47Here cold rolling process is employed for providing smooth and bright surface finish to previously hot

00:32:53rolled metal. Before cold rolling process, the hot rolled products are cleaned through pickling

00:32:58and other operations. Here part being rolled is generally analyzed and pickled before final pass is

00:33:04made so as to bring it accurate size and obtain perfectly clean surface. In hot rolling process,

00:33:10coefficient of friction between rolls and metal is higher, where in cold rolling process,

00:33:14coefficient of friction between rolls and metals is lower. In hot rolling process,

00:33:19heavy reduction in size is possible, where in cold rolling process, heavy reduction in size is not

00:33:24possible. In hot rolling process, close dimensional tolerances cannot obtain, where in cold rolling

00:33:30process, section dimensions can be finished to close tolerances. The surface finish in hot rolling process

00:33:36is poor, but in cold rolling process, smooth and oxidize-free surface finish can be obtained. In hot rolling

00:33:42process, rolled metal does not show work hardening effect, where in cold rolling process, rolled metal

00:33:48show work hardening effect. Next we will discuss the various types of press working operations.

00:34:01So, here punching is a machining process that involves removal of scrap metal from sheet of raw material.

00:34:06It requires use of punch press to compress tool through a sheet of raw material. Here punching tool

00:34:12pressed through sheet metal while placed against a die, where in piercing process, raw material is pierced

00:34:18with a machining tool resulting in creation of circular hole or other shape holes. During blanking process,

00:34:24a metal workpiece is removed from primary metal sheet when it is punched. Here material that is removed is

00:34:29the new metal workpiece. Notching is a metal cutting process used on sheet metal or thin bar stock.

00:34:36In notching operation, the material removes from edge of workpiece. Notching process is used in press

00:34:42so as to cut vertical down and perpendicular to surface working from edge of workpiece. Where in

00:34:47lancing operation, workpiece is sheared and bent with one strike of die and there is not reduction of

00:34:53material, there is only a modification of workpiece geometry. Next we will discuss

00:34:59slitting, trimming and shaving process. Here slitting is a metal sheet cutting process with circular knives

00:35:08which is used to split wide coil sheet into narrower width or for edge trimming of rolled sheet. Here slitter

00:35:15knives are mounted on two arbor together with spacers. The spacers determine width of cut. Here trimming is a

00:35:22metal cutting process of punching away excess material from the perimeter of a part as shown in figure.

00:35:28where shaving is a secondary metal cutting process that can be used to improve edge of cut that have

00:35:34already been made. Shaving uses very little clearance to perform straight smooth accurate cut to only

00:35:40end of edge. Shaving is a cheap removal type process and should not be used to cut large amount of cuts.

00:35:47Here bending operation is used to bend sheet metal or rod or pipes in desired shapes. Where in drawing

00:36:02operation, sheet metal blank is positioned over a die cavity and then bunch push the metal into opening

00:36:08forming convex or concave shapes. Here bending and drawing are the methods of shaping component parts

00:36:14mainly through plastic deformation of material. Now the third part is machining processes.

00:36:24So first we'll discuss the nomenclature of single point cutting tool.

00:36:28Nomenclature of single point cutting tool. The elements are cutting edge, face, nose radius,

00:36:35flank and these six angles. In that first one is back rake angle. This angle is between face of single

00:36:44point cutting tool and line parallel with base of tool measured in perpendicular plane through side

00:36:49cutting edge. Here if slope face is downward towards nose, it is negative back rake angle and if slope face

00:36:57is upward towards nose, it is positive back rake angle. Back rake angle helps in removing chip away from work piece.

00:37:08Next is side rake angle. It is the angle between surface of flank immediately below point and line

00:37:15down from point perpendicular to base. Side rake angle is the angle by which face of tool is inclined

00:37:23sideways. It determines thickness of tool behind cutting edge. It is provided on tool to provide

00:37:30clearance between work piece and tool to prevent rubbing of work piece. Next is end relief angle.

00:37:38It is the angle between portion of end flank immediately below the cutting edge and line

00:37:43perpendicular to base of tool measured at right angle to flank. End relief angle allows tool

00:37:51to cut without rubbing of work piece. Next is side relief angle. It is the angle between portion

00:37:58of side flank immediately below the side edge and line perpendicular to base of tool measured at right

00:38:05angle to side. Side relief angle prevents interference as tool enters the material. It is incorporated on tool

00:38:14to provide relief to provide relief between its flank and work piece surface. Next is end cutting edge angle.

00:38:22It is the angle between end cutting edge and line perpendicular to chunk of tool. This angle is provides clearance

00:38:29between tool cutting edge and work piece. Next is side cutting edge angle. It is the angle between straight cutting edge

00:38:39on side of tool and side of tool and side of shank. It is responsible for turning the chip away from finished surface.

00:38:50So, the next is tool signature for single point cutting tool. The convenient way to specify tool angles by use

00:38:56of standardized abbreviated system is known as tool signature. It indicates angles that a tool utilize during the cut.

00:39:04It specifies active angles of tool normal to cutting edge. Here are the seven elements that comprise its signature of

00:39:14single point cutting tool and are always stated in following order. A typical tool signature is shown here.

00:39:23Now, the next we will discuss the various length operations like turning, facing, taper turning,

00:39:30boring, knurling, tapping and forming operation. Here turning is the operation of removing excess material

00:39:38from work piece to produce cylindrical surface to desired length. Here the job is held between center or

00:39:45chuck and rotating at required speed. The tool moves in longitudinal direction to give feed towards

00:39:51headstock with proper depth of cut. In plane or straight turning operation, the work piece is held on

00:39:57chuck and it is made to rotate about the axis and the tool is feed parallel to lathe axis. Here straight turning

00:40:04produce a cylindrical surface by removing excess metal from work piece. Where in rough turning process,

00:40:10where removal of excess material from work piece in minimum time by applying high feed rate and heavy

00:40:15depth of cut. In rough turning process, average depth of cut 2 mm to 4 mm and feed is from 0.3 mm to 1.5 mm per

00:40:25revolution of work. And when work piece has different diameters and it is to be turned the surface forming

00:40:31steps from one diameter to other which is called as shoulder and machining this part of work piece

00:40:36is called as shoulder turning. Tapper turning process is used to produce conical shape by gradual reduction

00:40:43in diameter from cylindrical work piece. Here facing is the operation of reducing length of work piece

00:40:49by feeding perpendicular to lathe axis. For this operation, regular turning tool or facing tool

00:40:55may be used. Here cutting edge of tool set to same height as center of work piece. Here facing consists

00:41:01of two operations, roughing and finishing. In roughing, depth of cut is 1.3 mm. Where in finishing,

00:41:08depth of cut is 0.2 to 0.1 mm. Here chamfering is the operation of gating bevel surface at edge of

00:41:15cylindrical work piece. This operation is done in case of bolt ends and sharp ends. Chamfering helps to avoid

00:41:22damage to sharp edges and protect operations getting hurt during other operations. Chamfering on bolt

00:41:29helps to screw the nut easily. Here knurling is the operation of obtaining diamond shape on work piece

00:41:35for gripping purpose. This is done to provide better gripping surface when operated by hands. It is done

00:41:41using a knurling tool. The tool consists of a set of hardened steel rollers and it is held rigidly on tool

00:41:47post. Knurling operation is done at lowest speed available on lathe. It is done on handles and also

00:41:54in case of end of cages. The speed varies from 1 to 2 mm per revolution. Here two or three cuts may be

00:42:01necessary to give full impression. Thread cutting operation is used to obtain continuous helical

00:42:06grooves or threads. When the threads or helical grooves are formed on out surface of work piece,

00:42:11then it is called as external thread cutting. And when the threads or helical grooves are formed on

00:42:16inner surface of work piece, then it is called as internal thread cutting. The work piece is

00:42:21rotating between two centers, that is live center and dead center. Here tool is moved longitudinal to

00:42:27obtain required type of thread. When tool is moved from right to left, we get left hand thread. And when

00:42:34tool is moved from left to right, we get right hand thread. Here motion of carriage is provided by lead

00:42:40screw. Here pair of change gears drives lead screw and by rotating handle, depth of cut can be controlled.

00:42:47Filling operation is the finishing operation performed after turning operation. This is done on lathe to

00:42:52remove bars, sharp corners and feed marks on work piece and also to bring it to the size by removing

00:42:59small amount of metal. Here operation consists of passing flat single cut file over work piece

00:43:05which revolves at high speed. Here speed twice that of turning process. Polishing operation is performed

00:43:11after filling operation to perform surface quality of work piece. Grewing operation is the process of

00:43:17reducing diameter of work piece over narrow surface. It is done by Grew tool. Here Grew tool is

00:43:23similar to parting of tool. Now spinning operation is the process of forming thin sheet of metal by

00:43:29rotating job at high speed and pressing it against tailstock spindle. Here support is given from tailstock end.

00:43:36Spring winding is the process of making coil spring by passing wire around mandrel which is revolved on

00:43:42chuck or between centers. Here small hole is provided on steel bar which is supported by tool post and the

00:43:49wire is allowed to pass through it. Forming is the process of turning convex concave or any irregular shape.

00:43:56Forming tools are not supposed to remove much of material and is used mainly for finishing form

00:44:01surfaces. Generally two types of forming tools are used. Straight and circular. The straight type is used for wider application

00:44:08and the circular type for narrow surface. Now in lathe machine, drilling is the operation of producing

00:44:14cylindrical hole in work piece. It is done by rotating tool. Here rotating side of cutter known as drill.

00:44:20The work piece is revolving in a chuck or face plate and drill is held in tailstock drill holder or drill chuck.

00:44:27Here fitting is adopted by movement of tailstock spindle. This method is adopted for drilling

00:44:32regular shape work piece. Rimming is the operation of finishing and sizing a hole which has been

00:44:38already drilled or bolt. Here the tool is used is rimmer which has been multi-plate cutting edges.

00:44:44The rimmer is held on tailstock spindle either directly or through drill chuck and is held stationary

00:44:50while work is revolved at slow speed. Boring is the operation of enlarging hole which is already drilled.

00:44:56It cannot produce a hole. Boring is similar to external turning operation and can be performed in lathe.

00:45:02In this operation, the work piece is devolved in a chuck or face plate and the tool which is fitted to

00:45:08tool post is feed into work. It consists of boring bar having single point cutting tool that enlarges the

00:45:14hole. It also correct out of roundness of hole. This method adopted for boring small size work.

00:45:21The speed of this process is slow. Now counter boring is the operation of enlarging end of hole

00:45:26through certain distance. The operation is similar to boring. Here tool is used called as counter bore.

00:45:33The speed is slightly less than drilling. Now tapping is the operation of cutting internal threads

00:45:38of small diameter using multipoint cutting tool called as tap. In lathe machine, the work is mounted on chuck

00:45:44or face plate and revolved at slow speed. A tap of required size held on special fixture which is

00:45:50mounted on tailstock spindle. Now undercutting is the process of boring,

00:45:55groove or large hole at fixed distance from end of hole. This is similar to boring operation.

00:46:01Undercutting is done at end of internal thread or counter bore to provide clearance for the tool.

00:46:06Now some of lathe machine operation are performed by using special attachments. In that,

00:46:11milling is the operation of removing metal by feeding work against rotating cutter having

00:46:16multipoint cutting edges. For cutting keyways or grooves, the work is supposed on cross slide

00:46:22by special attachment and feed against rotating milling cutter held by chuck. Here,

00:46:27Depthop cut is given by vertical adjustment of work. The feeding movement is provided by carriage and

00:46:33the vertical movement of cutter is arranged in attachment. Grinding is the operation of removing metal

00:46:38in form of minor chips by feeding work against rotating abrasive wheel known as grinding wheel.

00:46:44Both internal and external surfaces of workpiece may be ground by using special attachment mounted on

00:46:49cross slide. For grinding external surface, work may be revolved between centers or chuck. For internal

00:46:55grinding, the work must be revolved on chuck or face plate. The feeding is done by the carriage and

00:47:00depth of cut is provided by cross slide. Grinding is performed in lathe for finishing a job, sharpening a

00:47:06cutter or sizing a workpiece after it has been hardened. Now, the next we will discuss, various types of

00:47:15drilling machines and various types of drilling operations. So, before that, first let us understand

00:47:23the nomenicature of twist drill tool. Here twist drill are rotary cutting tool that normally have two

00:47:30cutting edges and two fluids which are grooves formed in body to provide cutting leaves to permit

00:47:36removal of chips and allow coolant to reach the cutting action. They are identified by shung style.

00:47:42Here figure shows a schematic of design features for twist drill and the following terms used to

00:47:48design twist drill. So, here first is drill axis which is imaginary straight line which forms

00:47:54longitudinal center line of drill. Here drill diameter is the diameter over the margins of drill

00:48:01measured at periphery corners. Here fluids are helical or straight grooves formed in body of drill to

00:48:07provide cutting leaves to permit removal of chips and to allow cutting fluid to reach the cutting leaves.

00:48:13Here land is the peripheral portion of cutting tooth and drill body between adjacent fluids.

00:48:18Helix angle is the angle made by leading edge of land with plane containing axis of drill.

00:48:24Here body is a part of drill from its extreme point to commencement of neck. Here shung is a part

00:48:30of drill by which it is held and driven. The shung may be straight or taper. Here flank is the surface

00:48:36of drill which extends behind the leaf to fluid. Here margins is the cylindrical portion of land

00:48:41that is not cut away to provide clearance. Here point angle is the angle included between two leaves

00:48:47projected upon a plane parallel to drill axis and parallel to two cutting leaves.

00:48:52Here chassel edge is the point where two cutting leaves meet at extreme tip.

00:48:57Chassel edge angle is the angle included between chassel edge and cutting leaf as viewed from end of drill.

00:49:05Here lip is the cutting edge formed at intersection of flank and fluid. Here face is the fluid surface

00:49:11portion adjacent to lip. Here web is the central portion of drill situated between roots of fluids and

00:49:18extending from point towards shung. Here point end to web forms the chassel edge.

00:49:26Now the next we will see types of drilling machines.

00:49:28So there are seven types of drilling machines in market. Those are sensitive drilling machine,

00:49:36vertical or pillar type drilling machine, radial arm drilling machine, gang type drilling machine.

00:49:42So first type is sensitive drilling machine which consists of base, column, work table, drill head,

00:49:48feed mechanism, spindle, electrical motor and pulley. Here sensitive drilling machine has only hand feed

00:49:54mechanism for feeding the tool into work piece. This enable operator to feel how the drill is cutting.

00:50:00Accordingly he can control down feed pressure. Here base carries entire weight of machine and transfer

00:50:06the weight to ground. Here we use radial column so that movement of arm is possible in clockwise or

00:50:13in anticlockwise direction. At the top of column there is upper arm which carries drill head and also house

00:50:19of driving mechanism. Here work table is made up of cast iron and it is mounted on column. Here T-slot

00:50:25provided at top surface of table. The table can move up and down as also right or left according to job and

00:50:32tool arrangement. One side of arm a drill head is mounted which consists of various feed and driving

00:50:38mechanism. A V-type belt is provided to transfer power from motor to pulley and from pulley the mechanical

00:50:45power is transferred to drill head. In feed mechanism we use electrical motor, V-belt and pulley

00:50:52to transfer power from motor to spindle. Here spindle is a circular taper shaft which helps to hold the

00:50:58drill chuck. Here chuck is mounted on lower end of spindle. It holds drill jig. Here also keyhole is

00:51:03provided to change the drill jigs. The next is vertical or pillar type drilling machine which is

00:51:09free standing heavier construction, able to take larger drills. It has heavy frame to support wide range of

00:51:14work. The larger drills normally have tapper shunk located within the tapper bore in spindle end.

00:51:21In radial arm drilling machine, the workpiece is clamped in position on base. It is used for heavy large

00:51:27work. The arm is power driven for the height location. The drill head is positioned using motorized drives

00:51:33and it transfers the swinging arm. In gang type drilling machine, several spindles or stations are

00:51:39mounted on one long table. Where in multi spindle drilling machine, there are many spindles mounted

00:51:44on one head to allow many holes to drill simultaneously. Numerical control drilling machine can

00:51:50automatically change tooling with turret or automatic tool changer. And here speed, feed and table position

00:51:56is controlled using computer program. Now the next point is, various types of drilling machine operations.

00:52:05Drilling machine operations like drilling, rimming, boring, countersinking, counter boring, spot facing,

00:52:14tapping operation. So, first is drilling operation. In drilling, we produce a cylindrical hole inside

00:52:20workpiece. Here material is removed by rotating edge of cutting tool and the rotating edge is called as

00:52:26drill. In drilling operation, internal surface of hole is usually rough and hole is always bigger than drill

00:52:32size. Next is boring operation. Here we increase diameter of hole which was previously produced.

00:52:39Boring operation is done due to machining internal surface of hole which was produced by casting process.

00:52:45Boring operation is done due to correcting roundness of hole and finishing hole for making it of required

00:52:51size. The boring tool has only one cutting edge. Boring tool is placed in boring bar which was tapered

00:52:57chunk. The speed of spindle in boring is less than rimming operation. The spot facing operation is used for

00:53:04producing flat seat for bolt head, washer or nut at opening of real hole. It is used to give high surface

00:53:12finish at top of hole. Next is tapping operation. Here tap is used for making internal threads which can be

00:53:19fit into external threads of identical size. That means, here tap work as a cutting tool. Tapping operation

00:53:26can be performed by hand or you can also use external power for doing this. In counter boring operation,

00:53:32the end of hole is enlarged cylindrically. Here counter bore work as a tool. Counter bore consists of

00:53:39cutting edges. These cutting edges may be straight or spiral. The cutting speed in counter boring process

00:53:45is usually slow. This cutting speed is 25% smaller than that of speed in drilling.

00:53:51Next is rimming operation. Here before rimming, the size of hole after drilling process may not be

00:53:57perfect. Most of time, its internal surface may not be finished properly. Rimming is done to obtain

00:54:03desired size of hole. Also internal surface of hole gets approximately finished with this process.

00:54:09Here rimmer is used for rimming. Here rimmer is a multipoint cutting tool.

00:54:14The countersink operation is used to make cone shape enlargement at end of hole.

00:54:19Here included angle of conical surface may be 60 degree to 90 degree. Here countersink tool

00:54:25has multiple cutting edges on its conical surface. Now the next point is Milling machines.

00:54:34Column and Knee type milling machine. In this type the table is mounted on knee casting

00:54:40which in turn mounted on vertical slide of a main column. The knee is vertically adjustable on column

00:54:48so that table can be moved up and down to accommodate work of various heights.

00:54:54The column and knee type milling machine comprises of following important parts.

00:54:59In that first one is base. It is foundation member for all other parts.

00:55:04It carries column at its one end. Next is column. Column is the main supporting member mounted vertically

00:55:13on base. It is box shaped, heavily ribbed inside and houses all driving mechanism for spindle and table

00:55:21fit. The front vertical face of column is accurately machined and is provided with

00:55:28doughtail guideway for supporting the knee. Next is knee. The knee is rigid iron casting

00:55:35which slide up and down on vertical ways of column face. An elevating screw mounted on base which is

00:55:42used to adjust height of knee and it also support the knee. Next is saddle. Saddle is placed on top of knee

00:55:51and it slide on guideways which set exactly at 90 degree to column face. The top of saddle provides

00:56:00guideway for table. Next is table. The table rests on ways of saddle and travels longitudinally.

00:56:09The top of table is accurately finished and T slots are provided for clamping the work and other fixtures.

00:56:15Next is overhanging arm. It is mounted on top of column which extends beyond the column face.

00:56:25Next is front brace. It is an extra support which is fitted between knee and overhanging arm to ensure

00:56:32further rigidity to herbor and knee. Next is spindle. It is situated in upper part of column

00:56:38and receives power from motor through belts and gears. Next is herbor. It is like an extension of

00:56:46machine spindle on which milling cutters are securely mounted and rotated. The herbor are made with taper

00:56:53shung for proper alignment with machine spindle having taper hole at their nose. The drop volt is used for

00:57:01managing for locking the herbor with spindle and hole assembly. Construction working of reno miller.

00:57:12Here bed is fixed as a base of machine. The table is mounted on bed. Here are two vertical columns

00:57:18one on each side of bed. Crossrail is fitted on column. It may lower or riser to suit height of workpiece.

00:57:26Two vertical milling heads mounted on crossrail which can be moved towards each other. Two horizontal

00:57:33milling head mounted on column which can be moved vertical over it. The workpiece can be machined in

00:57:40four different ways according to requirement. That is by moving table and cutter rotate in this position.

00:57:47By keeping table stationary and feeding cutters by moving milling head.

00:57:51And by moving table and milling head simultaneously. And by keeping table stationary, moving crossrail

00:57:59downward and side cutter up and down. The plano miller is a large machine which has construction

00:58:05similar to planar machine. Instead of single point cutting tool, milling cutters are used.

00:58:11The main difference between planar and plano miller machine is table moment.

00:58:15These milling machines are constructed for heavy duty work and generally flat surfaces are to be machine.

00:58:24Modern plano miller are provided with high power driven spindles extent of 100 hp.

00:58:30It is suitable for piece production or batch production. Large job having parallel flat faces like

00:58:37lathe bed table of grinding machine, plenum machines can be produced.

00:58:41Now the next point is the working of horizontal brooching machine.

00:58:50So before that, first we'll discuss the nomenclature of brooching tool.

00:58:55So here I had drawn the sketch of brooching tool. In that first one is pulling end.

00:59:01Here pulling end is provided in pull brooch to attach pulling mechanism.

00:59:04Here is front pilot. It guides brooch in hole and also work as a roughing no go gauge.

00:59:12Next is rear pilot. Which determines size of finish hole. Here is chunk length or stroke length.

00:59:22It is the length to pass from workpiece and attach puller before roughing tint engage with workpiece.

00:59:28Now here rough teeth removes major material. While semi finished teeth provide smoothness while cutting.

00:59:37Here finishing teeth are of same height. It provides finishing to workpiece.

00:59:42Next is length. It is the uppermost portion of a tooth.

00:59:46Next is back off angle. It also known as clearance or relief angle. It prevents rubbing of length.

00:59:52Here are some profile. The back off angle is between 0.5 to 3 degree.

00:59:58Next is face angle. It also known as hook angle. It can be compared with rack angle of single point tool.

01:00:06Face angle is between 10 to 20 degree. Next is pitch. The pitch is the distance between same point on two

01:00:14successive teeth. Here are some profile which can be produced by brooching process.

01:00:22Now the next point is the working of horizontal brooching machine.

01:00:28So the horizontal brooching machine used to make key wedge spline slots on workpiece.

01:00:34Here workpiece is fixed on fixture and brooch is pulled.

01:00:39The sharp edges of brooch penetrate into workpiece.

01:00:42And due to shearing action plastic deformation of workpiece takes place.

01:00:48And metal removes in form of chips.

01:00:50The chips are collected in cheese space and it is removed when brooch comes out from workpiece.

01:00:59Here work holding fixture is used to hold the workpiece in proper position.

01:01:07Now the next point is centerless grinding process.

01:01:10So, here is the workpiece which passes between two wheels that is grinding wheel and regulating wheel.

01:01:21Both the wheels rotate in same direction but at different speeds.

01:01:25The purpose of grinding wheel is to remove material from workpiece to improve surface finish.

01:01:31The regulating wheels act like a brake. It controls rotational speed and throughput rate of workpiece.

01:01:38And the workrace blade supports workpiece as it passes through grinder between grinding and regulating wheel.

01:01:46Here the top angle of workrace blade helps with rounding action of workpiece.

01:01:51With increased angle, quicker rounding occurs but it also weakens the blade rigidity.

01:01:57The most common top angle used is 30 degree.

01:02:00The lower top angle are used when grinding heavy workpiece which help minimize in vibration.

01:02:06The centerless grinding process is commonly used for high volume production.

01:02:11Here regulating wheels are made up of rubber or plastic material.

01:02:14And the abrasive types used in grinding wheels are determined by workpiece material.

01:02:23Now the fourth part is molding processes.

01:02:27In that, first we will discuss plastic injection molding.

01:02:33Here screw is rotated to melt plastic which introduced from hopper and to accumulate molten plastic in front of a screw.

01:02:40After required amount of molten plastic is accommodated, injection process is started.

01:02:45While molten plastic is flowing in a mold and machine control moving speed of a screw.

01:02:50Here mold is hollow metal block into which molten plastic is injected to form certain fixed shape.

01:02:57And there are many holes drilled in a block for temperature control by means of hot water.

01:03:02Here molten plastic flow into mold through sprue and fill cavity by way of runner and gates.

01:03:08Then the mold is open after cooling process.

01:03:11An injector rod push the ejector plate of mold to further eject moldings.

01:03:17Here Tiber support and align the platen which then support the mold.

01:03:21Here mold consists of a screw to introduce molten resin.

01:03:25And runner lead molten resin into cavities.

01:03:28Here obtaining of only one product by one shot is very inefficient.

01:03:33So mold is designed to have multiple cavities connected with runner.

01:03:37So that many product can be made by one shot.

01:03:40Here cylinder temperature, injection speed and mold temperature are set in mold machine

01:03:45to obtain required molding condition.

01:03:47Depending on molding condition selected.

01:03:50The appearance, dimension and mechanical properties of molded product change accordingly.

01:03:55Therefore well tried technology and experience are required to select more suitable molding condition.

01:04:00Now the next point is, various types of plastic molding processes like compression molding,

01:04:10blow molding, extrusion, vacuum forming and calendaring method.

01:04:15In compression molding method, the mold is charged with major amount of powder which is to be compressed.

01:04:21Then plastic material is forced under compression to flow rapidly around the cavity.

01:04:26The heat from platen are caused the plastic to cure, resulting in permanent change in shape.

01:04:32Here the component is rejected from the mold and excess material formed at edges is removed.

01:04:38Thermosetting plastic material is used in compression molding.

01:04:41In blow molding method, compressed air is blown inside of parison which is in flat seat,

01:04:46pushing the soft plastic hard against cold surface of mold.

01:04:51The mold is open and molding ejected and the waste material is steamed off with a knife.

01:04:56The blow molding method is used to make bottles and other light wet hollow parts.

01:05:01And the materials used in blow molding are high density polyethylene and low density polyethylene material.

01:05:07In extrusion process, the dry plastic material is placed into hopper and feed into long heating chamber.

01:05:14Here turning screw pushes the plastic into barrel where heater increases temperature and melted polymer is obtained.

01:05:21At the end of chamber, the material is forced out of a small opening or a die in the shape of desired finished product.

01:05:28As the plastic exits the die, it is placed on conveyor belt where it is allowed to cool.

01:05:33This process of extrusion is usually used to make product such as film, continuous sheeting, tubes, profile shapes,

01:05:41rods, filaments, cords and cables.

01:05:44In vacuum forming method, the mold is attached to a platen. The platen and mold are then lowered.

01:05:50The rigid thermoplastic sheet material is clamped onto an airtight gasket and usually heated from the above.

01:05:57Once the thermoplastic sheet is softened, then air is blown in to raise the sheet in slight bubble

01:06:03before the platen is raised, bringing the mold into contact with plastic.

01:06:07Here trapped air remaining between the platen and the heated plastic sheet is then evacuated by the vacuum pump.

01:06:14Here atmospheric pressure acting over the top surface completes the forming process by pressing plastic sheet onto the mold.

01:06:22Once the plastic sheet has cooled down to below its freezing point, the air flow is reversed to leave the forming of the mold,

01:06:29the mold is lowered. This process is used to manufacture a variety of products in thermoplastic material.

01:06:35The most popular material is high impact polystyrene. It is relatively cheap, comes in wide range of colors and it is easy to form.

01:06:45In calendaring process, the melted polymer is subjected to heat and pressure in extruder and form into sheet or film by calendaring rolls.

01:06:54The temperature and speed of rolls are influences the properties of film.

01:06:58Here calendar is a series of hard pressure rollers used to finish or smooth a sheet of material such as plastic.

01:07:06Make me procedures forprendena's

01:07:13are Performing machines

01:07:14The temperature and speed of turns

01:07:25Fearing the type of silicon

01:07:30Be used to remove dri escaping

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