Gökhan Güngör (8th week - Missing Terms)

Dinking: Cutting of non-metallic articles from the sheet, usually involving such operations as blanking and piercing. (Ramalingam K.K., Handbook of Mechanical Engineering Terms, 2nd edition, p. 55)

Fullering: Similar to drawing and is a preliminary forging operation which results in an elongated section between two heavier sections. (Ramalingam K.K., Handbook of Mechanical Engineering Terms, 2nd edition, p. 58)
Heading: A metal gathering or upsetting operation. Originally used for production of screw and rivet heads in cold working process. (Ramalingam K.K., Handbook of Mechanical Engineering Terms, 2nd edition, p. 58)

2d laser processing systems: The 2D laser systems are used mainly for cutting, welding and hardening operations. The first industrial laser systems, the so called laser machining centers were occupied with a fixed beam delivery system. The workpiece was positioned relatively to the laser spot. Typical applications were turbine blade drilling, contact welding, etc. Nowadays, the laser systems available, can be used either as flexible manufacturing cells or as fully automated components of a production chain. (Chryssolouris G. Manufacturing Systems, 2nd edition, p. 158)
3d laser processing systems: The primary aspect of the 3D laser processing with two converging laser beams is the laser grooving process. Each beam creates a groove in the workpiece through single or multiple passes. A volume of material is removed when the two produced grooves intersect. Turning, milling and gear cutting operations can be accomplished with the use of this system. (Chryssolouris G. Manufacturing Systems, 2nd edition, p. 159)
Cupola: Special type of blast furnace, chiefly used for the melting of cast iron. (Ramalingam K.K., Handbook of Mechanical Engineering Terms, 2nd edition, p. 70)
Governor: A device for controlling the speed of a prime mover, that produces power. (Ramalingam K.K., Handbook of Mechanical Engineering Terms, 2nd edition, p. 71)

Pickling: Treatment of objects with an acid solution to remove all oxide, scale or dirt. Usually done to clean and brighten the surface, although sometimes used for etching. (Ramalingam K.K., Handbook of Mechanical Engineering Terms, 2nd edition, p. 144)
Seaming: A bending and flattening of an interlocking fold, e.g., a stove pipe seam. (Ramalingam K.K., Handbook of Mechanical Engineering Terms, 2nd edition, p. 62)

Thermit: Powdered form of finely divided iron oxide and aluminium which burns intensely to produce superheated liquid steel at a temperature of about 30.35°C, used for welding wrought iron and steel forgings and castings. (Ramalingam K.K., Handbook of Mechanical Engineering Terms, 2nd edition, p. 36)

Gökhan Güngör (8th week)

1- Dinking
2- Fullering
3- Heading
4- 2d laser processing systems
5- 3d laser processing systems
6- Cupola
7- Governor
8- Pickling
9- Seaming
10- Thermit

Evrim Berk 030060161 8th Week

Rolling Through Time

In requirements planning environments, as a result of the limited visibility into the future, the manufacturers often plan their replenishment schedules on a rolling horizon basis. Using the currently available data, they determine their best replenishment quantities over a specified planning horizon and implement a subset of the earlier replenishment decisions. After rolling through time, the schedules are updated utilizing recently collected data.

Application of rolling schedules is common in industry; however, appropriate use of rolling schedules requires careful consideration as it poses many challenges for channel integration. First of all, one needs to be aware of the limitations of rolling schedules. Even if the best possible replenishment schedule is determined in each planning cycle, the long-term replenishment schedule may not necessarily represent the best possible schedule. This is usually the result of the length of each planning cycle. If each cycle is not long enough, it is not possible to determine the best replenishment schedule that would be found knowing demand beyond the end of the planning cycle.

(Supply Chain Coordination Through Schedule Integration, Sahin F., 2008, Page #1)

First Day Load

When resources have excessive loads the workload will be pushed backward until the load on the first day is greater than the available capacity. Such a condition is referred to as a first-day-load peak and reveals the presence of a constraint resource.

(Manufacturing planning and control for supply chain management, Vollman T.E., Page #558)

Dyad by Dyad Approach

A dyad by dyad approach means that pairs of organizations jointly develop the new processes and MPC systems that allow them to ever more effectively integrate their detailed operations. It is dyad by dyad because the joint working and definitions of improvement projects will tend to be unique to the dyad. This said, best practice will be able to learn as mush as possible from each dyad improvement effort, and then imbed the MPC thinking, processes, and systems int modular approaches to whatever extent possible. That is, one should work hardest with smart partners where new chain benefits are achived, but then try to leverage the learning in other dyads."

(Manufacturing Planning and Control For Supply Chain Management, T. E. Vollmann, page# 665)

Flexible Systems

Leading-edge firms are coming to understand requirements for volume and product flexibility. Some have had experience in repetitive manufacturing applications of JIT and are moving into nonrepetitive applications. An example is a telecommunications equipment manufacturer, which began JIT in its high volume telephone handset operations. The firm had a limited number of high-selling models; in two years its inventory turns were tripled, work in process was reduced by 75 percent, failure rates in manufacturing were cut in half, and setup times fell 50 percent. Thereafter, the firm turned to its low-volume telecom systems plant, where more than 150 basic circuit boards were manufactured, and every end item was somewhat of a custom order. The company learned it needed to go back to the basics of JIT - product engineering, process engineering, and the whole person concept - to successfully implement JIT for its nonrepetitive products.

The firm developed cellular designs, began cellular manufacturing with freat flexibility, and cross trained people with an emphasis on being able to handle volume surges in the telecom systems plant. MRP was still used for overall planning, but far fewer transactions were processed by the hidden factory of indirect labor. In the first six months, first pass yields improved 27 percent, work in process fell 31 percent, and manufacturing cells under JIT hit 100 percent of schedule. The people then helped out other parts of the company that were behinde schedule.

(Manufacturing Planning and Control For Supply Chain Management, T. E. Vollmann, pages321-322)

Kayra Ermutlu-030060081 (8th Week)

Uni-Directional Roller Clutches

Roller Clutches are less noisy than toothed clutches. There is lesser engaging shock during engagement. Roller clutches can be operated at much higher speeds (up to 4 m/sec) than toothed cluthes (0.7 m/s). Their simple design and ease in manufacture make them convenient for use in uni-directional operation, despite a bigger size and rapid wear. The wear is minimized by using hardened inserts at the contact faces.

(Joshi P.H., Machine Tools Handbook: Design and Operation, pg.332, Kayra Ermutlu)

Mechanical Alloying

Mechanical alloying is a high energy dry ball milling process used to make composite metallic powders with a controlled fine microstructure. Powders of the desired composition are blended and then placed in a high energy ball mill. The intensive milling process repeatedly fractures and then rewelds the powder particles. During each collision with the grinding balls, the particles are plastically deformed to the extent that the surface oxides are broken, exposing clean metal surfaces.

On subsequent impacts, the clean surfaces are welded together. This cold welding process increases the size of the particles, while at the same time additional impacts are fracturing particles and reducing their size. As the process continues, the microstructure of the particles is continually being refined. Milling is continued until every powder particle contains the same composition as the starting mix.

(Campbell F.C., Manufacturing Technology for Aerospace Structural Materials, pg.232, Kayra Ermutlu)

Tape Forming

Tape formingis used to make thin ceramic parts like alumina substrates for integrated circuit chips and special capacitor. A thin layer of slip is laid on a flat carrier which can be a paper sheet or polymer film. A doctor blade controls the slip thickness, resulting in a tape that can be stamped into small shapes. These can be stacked or coiled for subsequent sintering.

(Ohring M., Engineering Materials Science, Part I, pg.420, Kayra Ermutlu)

Mechanical Overload

As the name implies, This type of fracture results when load applied exceeds the available strength of a component. This seems straight forward enough, but there are some subtleties. For example, "What is the available strength of a component?". Actually, it is a function of two things. It is derived from both the inherent strength of the material and how much of that material is available to carry the load. If the material strength is compromised (through alteration of its heat treatment, for example) then the strength of that component is not as intended. Similarly, if the amount of load bearing material is deminished (through corrosion or cracking) then the component is similarly weakened.

(Broker J.P., Hill P.F., Bicycle Accidents: Biomechanical, Engineering, and Legal Aspects, pg.242, Kayra Ermutlu)

A. Selim PARLAKYİĞİT - 8th Week

1. Hot Dipping
2. Sputtering
3. Chromizing
4. Boronizing
5. Carbonitriding
6. Superfinishing
7. Buffing
8. Chemical Blanking
9. Air Carbon Arc Cutting
10.Photolithography (Optical Lithography)

Bugra Cengiz 030060178 8th week

Stiffness
Stiffness is a measure of  a systems's resistance to deformation. A rubber band is easily deformed by hand but a steel wire or rod of the same cross-sectional area is not. The stiffness of steel is greater than that of rubber.

Frederick A. Leckie,Dominic J. Dal Bello, The strength and the stiffness of The Engineering Systems, P.48 

Implsion (Implosion Hazard)


The pressure differance (0,1MPA) between inside of the vacuum enclosure and outside initiate an accidental implosion of an evacuated birttle containeer, resulting in flying fragments. Glass and perspex viewports represen an implosion hazard. 

R. Hellborg, Electrostatic accelerators: fundamentals and applications, P.366

Flexible Systems (Flexible Productio Systems)
Mass production is predicated largely on the principles of Frederick W. Taylor. one of the leaders of the scientific management movement in the early 1901s.  According to Taylor, workers had to be told every detail of their work methods and were incapable of planning their own tasks. By comparison.Lean production makes use of worker teams to organize the tasks to be accomplished and worker involvement to solve technical problems. One of the findings reported in The Machine thai Changed the World was that workers in Japanese "lean production" plants received many more hOUTSof training than their U.S, counterparts (380 hours of training vs.46 hours).Another finding was the lower number of job classifications in Japanese lean plants. The study showed an average of 11.9 job classifications in Japanese plants versus an average of 67.1 in L:.S. plants. Fewer job classifications mean more cross-training among workers and greater nexttunty ill the work force.                                  
     In mass production, the goal is to maximize efficiency. This is achieved using long
production runs of identical parts. Loeg production runs tolerate long setup changeovers, In lean production. procedures are designed to speed the changeover. Reduced setup times allow for smaller batch sizes. thus providing the production system with greater flexibility. Flexible production systems were needed in Toyota's comeback period because of the much smaller car market in Japan and the need to be as efficient as possible.


Groveer, Automation, Production Systems and CIM, P. 835

ÖMER TAYLAN BOYA 030070099 8th WEEK

Planer (machining) (9:50 am 01.04.2011)

Planer and shaper are popular single point precision machining methods. A shaper operates by moving a cutting tool backwards and forwards across the workpiece. The workpiece mounts on a rigid square table that can traverse sideways underneath the reciprocating tool, which is mounted on a ram. The table motion is controlled by a precise feed mechanism. The ram slides back and forth about the workpiece and the tool can be positioned to cut the flat surface on the top of the workpiece. A Planer is a type of machining tool analogous to a shaper, but larger and with the entire workpiece moving beneath the cutter instead of the cutter moving above a stationary workpiece. Planers and shapers are generally used for two types of work: generating large accurate flat surfaces and cutting straight microgrooves. Modern planers are used for producing precision stamping dies and plastic injection molds for light-guiding plates of liquid crystal displays, large scale linear fresnel lenses.

( J. Paulo Davim, Mark J. Jackson, Nano and micromachining, page 178)

Carriage ( about lathe) ( 10:04 am 01.04.2011)

Carriageis mounted on the outer guideways of lathe bed and it can move in a direction parallel to the spindle axis. It comprises of important parts such as apron, cross slide, saddle, compound rest and tool post. The lower part of the carriage is termed the apron in which there are gears to constitute apron mechanism for adjusting the direction of the feed using clutch mechanisms and the split half of nut for automatic feed. The cross slide is basically mounted on the carriage, which generally travels at right angles to the spindle axis. on the cross slide , a saddle is mounted in which the compound rest is adjusted which can rotate and fix to any desired angle. The compund rest slide is actuated by s screw, which rotates in a nut fixed to the saddle.

(Rajender Singh, Introduction to basic manufacturing processes and workshop technology, page 410)

Abrasive Wear (16:04 03.04.2011)

Abrasive wear is defined as wear due to hard particles or hard protuberances forced against and moving along a solid surface. This form of wear in metals is most frequently caused by non-metallic materials but metallic particles can also cause abrasion. Generally a material is seriously abraded or scratched only by a particle harder than itself.

(Joseph R. Davis Surface Engineering for Corrosion and Wear Resistance, page 56)

Addition Polymerization (16:34 03.04.2011)

Addition polymerization is the polymerization of the monomers by a chain mechanism involving active sites on the growing chain. Addition polymerization is frequently accomplished with unsaturated monomers, it is also called vinl polymerization when the unsaturated monomer contains the group -CH2=CH2-

(Charles A. Harper, Edward M. Petrie, Plastics materials and processes: a concise encyclopedia page 13)

Burcu Atay, 140060029, 8th week

Hydraulics

Hyraulic motors are mainly used for heavy-duty machines that require high torque or force. Control of hyraulic motor is, however, more difficult due to nonlinear characteristics of various components in the hyddraulic system. These actuators are used to construct feed drives and, therefore, are required to have good velocitycontrollability. Asignal from the controller is amplified and supplied to the motor. The motor produces a torque to rotate the shaft through a coupler, while linear motors drive the table directly. The position or velocity signal measured by an encoder, a resolver, or a

tachometer is fed back to the controller so that closed-loop control of the feed drive can be achieved.

(Dorf, R.D., Kusiak, A., Handbook of Design, Manufacturing and Automation,1994, pg.247)

Cladding

Explosive welding or cladding, as it is often called, brings together two metal surfaces with sufficient impact and pressure to bond. Pressure is developed by a high-explosive shot placed in contact with or in close proximity to the metals. In some instances a protective material such as rubber is placed over the upper panel to prevent damage to the surface. The entire assembly is placed upon a buffer plate or anvil to absorb energy generated during yje jıining operation. Of the two arrangements showing cladding or laminating of metals, the left one is preferred.

To obtain a metallurgical bond, atoms from boh surfaces must come into intimate contact. The oxides and films always present on the surface of metals are broken or dispersed by high

pressure or dissolved in the molten region. The explosive force brings the clean surfaces together and produces a sound bond.

(Amstead, B. H., Ostwald,P. F., Begeman, M. L., MAnufacturing Processes,8th Edition, pg. 189)

Cupola

Heat is provided externally ( for example, by electric, gas , or oilheating), internally(as by electic induction) or, only for cast iron, by mixing the fuel with the charge itself. CAst iron is usually melted semicontinuously in a vertical shaft furnace (cupola); lining of the cupola with a refractory is being abondened in favor of water-cooled steel jackets. The charge is mixe

d with coke and some minerals(primarily limestone, CaCO3), and hot air is blown through the column. Coke burns to give heat and is also a source of carbon for the cast iron. The liquid metal is tapped at the bottom, seperately from the slag which is formed by the limestone with nonmetallic contaminants and metal oxides. In the duplex process, the liquid metal is tapped into an electic holding furnace where alloying and suğerheating is also practiced.

(Schey, J., A., Introduction to Manufacturing Processes, 2nd Edition, pg.148-149)

Feedforward Control

The strategy in feedforward control is to anticipate the effect of disturbances that will upset the process by sensing them and compansating for them before they can affect the process. As shown in Figure, the feedforward control elements sense the presence of a disturbance and take corrective action by adjusting a process parameter that compensates for any effect the

disturbance will have on the process. In the ideal case, the compensation is completely effective. however, complete compensation is unlikelybecause of imperfections in the feedback measurements, actuator operations, and control algorithns, so feedforward control is usually combined with feedback control, as shown in our figure. Regulatory and feedforward control are more closely associated eith the process industries than with discrete production manufacturing.

(Groover, M. P., Automation, Production Systems and Computer-Integrated Manufacturing, 3rd Edition, pg.93)

Ozlem Salman (8. week)

1 Hydraulics 2 Pneumatics 3 AC motor 4 DC motor 5 Stepper motor 6 Servomechanizm 7 Potentiometer 8 3D blow molding 9 Coextrusion 10 Octree represantation

Gani Can Öz - 8th Week

1	Crank Mechanism
2	Lever Mechanism
3	Ratchet Mechanism
4	Pantograph Mechanism
5	Cam Mechanism
6	4 Bar Linkage
7	Ferguson's Paradox
8	Hook's Coupling (Universal Joint)
9	Toggle Joint
10	Worm Gear

Gani Can Öz - 503101305