FORMING

DEFINITION  :
         The process of the loss of stability is analysed for sheet metal subjected to biaxial tension when the ratio of the principal stresses 
$\text{0.5 ⩽ σ}{}_2\text{/σ}{}_1\text{⩽ 1}$. The loss of stability manifests itself by a groove running in a direction perpendicular to the larger principal stress. In this groove local strains begin to concentrate gradually. In the initial stage of the process the deepening of the groove is associated with a gradually fading strain in the regions adjacent to the groove. This fading strain attains a certain limiting value ...

Roll forming, also spelled rollforming, is a type of rolling involving the continuous bending of a long strip of sheet metal (typically coiled steel) into a desired cross-section. The strip passes through sets of rolls mounted on consecutive stands, each set performing only an incremental part of the bend, until the desired cross-section (profile) is obtained. Roll forming is ideal for producing constant-profile parts with long lengths and in large quantities.

Forging defined

At its most basic level, forging is the process of forming and shaping metals through the use of hammering, pressing or rolling. The process begins with starting stock, usually a cast ingot (or a "cogged" billet which has already been forged from a cast ingot), which is heated to its plastic deformation temperature, then upset or "kneaded" between dies to the desired shape and size.

Advanced Manufacturing Technology Research Group

In close collaboration with academic and industrial partners and with a focus for aerospace, automotive and medical application, the research team carries out fundamental and applied research in the following areas:

New flexible and hybrid material forming processes

Process modelling and optimisation

Material characterisation, constitutive models, formability and fracture

Friction stir welding and processing of lightweight materials

Tribological behaviour in bulk and sheet forming processes

FORGING

DEFINITION OF Hot forging and cold forging :-
                               Hot forging and cold forging are two different metal forming processes that deliver similar results. Forging is the process of deforming metal into a predetermined shape using certain tools and equipment—deformation is accomplished using hot,cold, or even warm forging processes.   
  

Cold and Hot Forging: An Overview

Forging is a metal shaping process in which a malleable metal part, known as a blank, billet or work-piece, is worked to a predetermined shape by one or more processes such as hammering, upsetting, pressing, rolling and so forth. Cold forming is a precision category of forging which does the same thing without heating of the material (room temperature), or removal of material

Among all manufacturing processes, forging technology has a special place because it can be used to produce parts of superior mechanical properties with minimum waste of material.

Forging can be produced at multiple temperature levels. Room temperature (or heat added process) forging is commonly called cold forging. This process is less costly, less heat energy consuming, provides greater dimensional accuracy, and can be very efficient for mass production of small parts (less than 50lbs). The downfall is that it requires much larger pressures to form the metal requiring large machinery and more frequent tool wear .

 is also important to remember that some technologies are unbeatin Courmayeur in 1909 the family was already renowned among alpinists for the quality of their ice axes. The story goes that old Henry, controversial and always ready to take the mickey, used to convince even the most wary clients of the strength of his tools were by striking them on the huge block of granite outside his workshop. But where did this strength and above all this self confidence come from Precisely from the technique of hot drop forging, exactly the same that produced the blades of the Sword o Damascus and of Toledo, world famous for their superior strength.

Steel doesn't have the cold and uniform characteristics that we usually give it but is instead groups of molecular chains that line up and distribute themselves according to lines of force that create the strength of the piece of 'iron'. A bit like fibres in wood that we're used to seeing and choosing according to their natural formation to get the best possible stamina. The huge advantage of steel is that it can be shaped to how we want it when it is heated to 'cherry red' temperature (about 950'C). Mantice At this point it can be modified through being beaten to align its fibres according to the lines of force needed to obtain the maximum strength in the direction that 

we want: for example following the length of an ice axe's blade

To summarise: the fibres in steel are internally aligned in a casual sequence, these can be re-aligned which ever direction we want when the steel is heated to a certain temperature and then 'ironed out' by beating it and forcing it into the desired alignment. This operation, followed up by heat treatment (what was once known as 'tempering' that fixed permanently the internal structure), is precisely known as 'hot forging'. It is how the best characteristics and the desired form are obtained from steel. No other process has ever, and ever will, better this one: quiz a specialist in metallurgy an

WELDING DEFECT

  Welding Defects can be defined as the irregularities formed in the given weld metal due to wrong or incorrect welding patterns, etc. The defect may differ from the desired weld bead shape, size, and intended quality. Welding defects may occur either outside or inside the weld metal. Some of the defects may be allowed if the defects are under permissible limits but other defects such as cracks are never accepted.

 Undercut

          Most structural failures originate from weld joint because it is the source of discontinuity or defects. The most visible weld defect we can easily find in visual inspection is undercut, shown in Figure 1 below. Undercut is usually due to overcurrent in electric arc welding. Overcurrent causes wide melting zone in base metal but not enough weld fusion metal to replace the gap. High lapping speed also leaves the gap poorly filled with weld fusion metal and produces undercut 

To avoid undercut, welder and welding inspector must observe initial weld lap to see whether the current setting is appropriate. Post welding inspection can be tricky since welder can cover undercut by running another lap using lower grade welding electrode and low current. Undercut is dangerous because it amplifies the stress flow due to reduction in section area and stress concentration of the notch form.


            Troubleshooting Weld Defects
Like any portion of the manufacturing or fabrication process, the welding operation is subject to human error from time to time. When weld defects occur as a result of a problem with welding operator's technique or poor equipment settings, it can cause costly downtime and rework, not to mention, frustration. 



When a weld defect appears, it's important for welding operators to have the knowledge they need to rectify the situation as quickly as possible. Faster troubleshooting leads to greater opportunities to add value to the welding operation — through increased productivity and quality improvements.

                                  Cold Cracks in Fillet Welds

VARIATIONS OF COLD CRACKS

Cold cracks are defined as cracks that occur at temperatures of 200-300°C or lower in carbon steel and low-alloy steel welds. Cold cracks can occur in both butt welds and fillet welds; however, this article will focus on those occurring in fillet welds.

IC ENGINE

Definitions

                   internal combustion engine a type of engine that is used for most vehicles : an engine in which the fuel is burned within engine cylinders....

Here, the fuel is burnt inside the cylinder of the engine. Chemical energy of the fuel is converted to thermal energy and thermal energy is converted to mechanical energy, which moves the piston up and down inside the cylinder. Power from the piston is transmitted to the crankshaft which is ultimately transmitted to the wheels via a transmission system.Modern automobiles use internal combustion engines for propulsion.

An Internal Combustion Engine (IC Engine) is a type of combustion engine that converts chemical energy into thermal energy, to produce useful mechanical work. In an IC engine, combustion chamber is an integral part of the working fluid circuit.

Reciprocating internal combustion engines—a subclass of heat engines—can be operated in the four- and two-stroke cycles. In each case, the engine may be equipped with either a spark-ignited (SI) or a compression-ignited (CI) combustion system. A number of other engine classifications are possible, based on engine mobility, application, fuel, configuration, and other design parameters. The combustion process can be theoretically modeled by applying laws of mass and energy conservation to the processes in the engine cylinder. Basic design and performance parameters in internal combustion engines include compression ratio, swept volume, clearance volume, power output, indicated power, thermal efficiency, indicated mean effective pressure, brake mean effective pressure, specific fuel consumption, and more.

Table of Contents

1. Introduction
2. Feasibility of technology and operational necessities
3. Status of the technology and its future market potential
4. Contribution of the technology to protection of the environment
5. Climate
6. Financial requirements and costs
7. References

Direct fuel injection is a technique that allows gasoline and diesel engines to run more fuel efficient. Direct injection techniques are already commonly used in modern diesel engines and are becoming more and more established for gasoline engines. Direct injection engines can lower the CO₂ emission of the vehicle by about 15% with low extra costs compared to other techniques leading to similar CO₂ emission reduction. 

However, still two thirds of all gasoline powered internal combustion engine vehicles which are sold worldwide are equipped with an internal combustion engine with indirect injection. Direct injection in diesel engines leads to small reductions in NO_x and particulate matter emissions which affect local air quality. However, direct injection in gasoline engines can lead to a small increase of NO_x and particulate emissions..

Green logistics

Green logistics Definition : - 
                                    Green logistics describes all attempts to measure and minimize the ecological impact of logistics activities. This includes all activities of the forward and reverse flows of products, information and services between the point of origin and the point of consumption.
     

Logistics is the integrated management of all the activities required to move products through the supply chain. For a typical product this supply chain extends from a raw material source through the production and distribution system to the point of consumption and the associated reverse logistics. The logistical activities comprise freight transport, storage, inventory management, materials handling and all the related information processing.

ELECTRICAL TRANSPARENCY

 Definition :- 
                           Transparent conducting oxides (TCOs), which have high transparency through the visible spectrum and high electrical conductivity are already being used in numerous applications. ... A thin conducting layer on or in between the glass panes achieves this.

The audio speaker represents a robust proof of concept for ionic conductors because producing sounds across the entire audible spectrum requires both high voltage (to squeeze hard on the rubber layer) and high-speed actuation (to vibrate quickly)—two criteria which are important for applications but which would have ruled out the use of ionic conductors in the past.

To make the speaker, a membrane of transparent, insulating rubber is sandwiched between two layers of transparent, conductive gel. The electrical connection to the power source is established outside of the active region of the device, where it does not need to be transparent. Credit: Christoph Keplinger, Jeong-Yun Sun...

The traditional constraints are well known: high voltages can set off electrochemical reactions in ionic materials, producing gases and burning up the materials. Ions are also much larger and heavier than electrons, so physically moving them through a circuit is typically slow. The system invented at Harvard overcomes both of these problems, opening up a vast number of potential applications including not just biomedical devices, but also fast-moving robotics and adaptive optics.

 "It must seem counterintuitive to many people, that ionic conductors could be used in a system that requires very fast actuation, like our speaker," says Sun. "Yet by exploiting the rubber layer as an insulator, we're able to control the voltage at the interfaces where the gel connects to the electrodes, so we don't have to worry about unwanted chemical reactions. 

The input signal is an alternating current (AC), and we use the rubber sheet as a capacitor, which blocks the flow of charge carriers through the circuit. As a result, we don't have to continuously move the ions in one direction, which would be slow; we simply redistribute them, which we can do thousands of times per second."

Power Minister Launches App For Transparency In Due To Gencos From Discoms
                The power ministry on Tuesday launched a web application that seeks to bring transparency in dues of power generators from power distribution companies. The app—christened Prapti (payment ratification and analysis in power procurement for bringing transparency in involving of generators—will bring transparency in the payments due to power producers from power distribution companies, power minister R K Singh said. The minister said health of power generator companies was a concern. “This app will go a long way in addressing it. Prompt payments will make generators healthier,” he said, adding this will also enable the banks to recover dues in time.

TRANSPARENCY

Transparency is woven into the fabric of everything we do.

 Information about our investment philosophy, process and fee structure is freely available, as are performance data for your portfolio. We share the underlying rationale for our recommendations, as well as your other options. There are no “black boxes,” and we strive to make our regular reporting clear, straightforward and easy to understand.

In addition to routine reports and our client portal, you’ll find that we frequently share market observations, analysis and insights through our own client communications. We hold client events to encourage discussion and dialogue, and we love to hear from clients whenever they want to talk or have a question.

We practice information sharing and open communication because we believe that informed clients are essential to effective relationships and long-term financial success.

ACTIVE ELECTRICALLY CONTROLLED SUSPENSION

Definition :-
                          From Wikipedia, the free encyclopedia. Active suspension is a type of automotivesuspension that controls the vertical movement of the wheels relative to the chassis or vehicle body with an onboard system, rather than in passive suspension where the movement is being determined entirely by the road surface.


With respect to weight, energy consumption, and cost constraints, hydro-active suspension system is a suitable choice for improving vehicle ride comfort while keeping its handling. The aim of sensors selection is determining number, location, and type of sensors, which are the best for control purposes.
    Selection of sensors is related to the selection of measured variables (outputs). Outputs selection may limit performance and also affect reliability and complexity of control systems. In the meanwhile, hardware, implementation, maintenance, and repairing costs can be affected by this issue. In this study, systematic methods for selecting the viable outputs for hydro-active suspension system of a passenger car are implemented. 

Having joint robust stability and nominal performance of the closed loop is the main idea in this selection. In addition, it is very important to use these methods as a complementation for system physical insights, not supersedes. So, in the first place the system is described and the main ideas in ride comfort control are addressed. An 8 degrees of freedom model of vehicle with passive suspension system is derived and validated. Both linear and nonlinear models of the car which is equipped with hydro-active subsystem are derived. 



After selecting the outputs, for benefiting from minimum loop interactions, the control configuration is systematically determined. The main goal of selecting control configuration is assessing the possibility of achieving a decentralized control configuration. 
Finally, the system behavior is controlled by a decentralized proportional–integral–differential (PID) controller. The results indicate the efficiency of the controlled hydro-active suspension system in comparison with the passive system.

BUILD 7128 – SUBFRAME AND SUSPENSION

Earlier installments of Build128 have taken you through, step-by-step, in how we perform some of the processed we undertake as we construct our cars. From the tub chassis, to the exterior panels, to the preparation and paint stages of the build.   

As with our last instalment – the koenigsegg engine t– we’re going to talk in coming instalments about why we do things the way we do, rather than concentrating on how.

 It’s one thing to tell you that a guy screws a part in to point ‘A’ on the chassis. It’s a different thing, and a more imhportant thing, to tell you what that part does and why it exists.To our subframe and suspension, then…..At this point in production, the panels have been removed from the car at the end of Station 2 and are sent to Station 3/4 for preparation, paint and polishing. 

While all that’s happening, the tub chassis moves along to Station 5, at which point the chassis is prepared to receive the engine, gearbox and front/rear subframes and suspension.Technicians on Station 5 prepare the chassis for the subframe by fitting a lot of the ancillary items to the chassis. In the photo below, you can see that heat-shields have been fitted, along with the battery and other fittings

Michelin’s Active Wheel technology has been around for the past couple of years but actual applications of the electronic powertrain and handling management system are still hard to come by. Over the years the technology has been showcased in a number of concepts, and at this week’s Paris Motor Show Michelin unveiled the latest generation of its innovative design in the new Volage  electric roadster concept from Monaco’s Venturi.

The Active Wheel is essentially a standard wheel that houses a pair of electric motors. One of the motors spins the wheel and transmits power to the ground, while the other acts as an active suspension system to improve comfort, handling and stability. The system is designed for battery or fuel-cell powered electric vehicles, and the technology is such that a vehicle equipped with it will no longer need any gearbox, clutch, transmission shaft, universal joint or anti-roll bar.

Active Wheel’s compact drive motor and integrated suspension system has also enabled designers to fit a standard brake disc between the motors, which means the braking, drive and suspension components are all fitted within the single wheel.Depending on the amount of power or type of usage desired, a given vehicle may feature up to four Active Wheels for AWD traction. The system also allows torque from the motors to be electronically controlled for each individual wheel independently. The results are similar to the effects of an active differential, allowing a vehicle with Active Wheel technology to make much faster turns in poor conditions than traditional shaft-driven vehicles.For the suspension, an electric motor controls an actuator connected to a damping system with varying levels of firmness. This unique system features extremely fast response time—just 3/1000ths of a second and all pitching and rolling motions are automatically corrected.

OPTICAL MEASURING INSTRUMENTS

Definition 
                   Optical Measuring Instruments. (in machine building), instruments in which sighting (alignment of the boundaries of the dimension being checked with a reference line or with cross hairs) is done or a dimension is determined by means of a device with an optical principle of operation.
                       

Surveying Process

The surveying process is a procedural one and, by following these instructions, you should be able to survey an entire stage from beginning to end.

The order of the survey process:

physical setup of survey instruments

configure data collector

• measure and store points
• move to another physical location (if necessary)
• finish measuring points
• export points

The survey process can take anywhere between 1-5 hours depending on the size of the stage and visibility of targets.  Stages with wires and lights in the way of the targets will take longer because you will need to move the survey instrument to multiple locations to capture all points.

• Total Station with Reflectorless Mode – this allows the total station to take measurements without the use of a prism or reflective stickers.
• Right Angle Eye Piece – for surveying points overhead, a 90-degree eye piece makes it easier to see the targets.
• Total Station Tripod  and Spreaders – the tripod and tripod spreader are important tools.  Without these, the survey gun cannot be properly leveled.
• Data Collector – this is a separate piece of hardware that acts like a handheld computer.  The Data Collector is able to store and output point data as well as configure the total station.
• Bluetooth Data or Serial Data Cable for Data Collector – for the Data Collector to communicate with the Total Station, you will need either Bluetooth connectivity or a hard wired serial cable connection.  We recommend having a cable as Bluetooth often drops out in sound stages.

Digital Tachometer Circuit Operation using Microcontroller and their Types

A digital tachometer is a digital device that measures and indicates the speed of a rotating object. A rotating object may be a bike tyre, a car tyre or a ceiling fan, or any other moter , and so on. A digital tachometer circuit comprises LCD or LED read out and a memory for storage. Digital tachometers are more common these days and they provide numerical readings instead of dials and needles.

Digital tachometer is an optical encoder that determines the angular velocity of a rotating shaft or motor. Digital tachometers are used in different applications such as automobiles, aeroplanes, and medical and instrumentation applications.

Height gauge

A height gauge is a measuring device used for determining the height of objects, and for marking of items to be worked on.These measuring tools are used in metal  working or metrology to either set or measure vertical distances; the pointer is sharpened to allow it to act as a scriber and assist in marking out work pieces.

Devices similar in concept, with lower resolutions, are used in health care settings (HEALTH CLINICS , SURGERIES,) to find the height of people, in which context they are called   stadiometers . 

Height gauges may also be used to measure the height of an object by using the underside of the scriber as the datum. The datum may be permanently fixed or the height gauge may have provision to adjust the scale, this is done by sliding the scale vertically along the body of the height gauge by turning a fine feed screw at the top of the gauge; 

then with the scriber set to the same level as the base, the scale can be matched to it. This adjustment allows different scribers or probes to be used, as well as adjusting for any errors in a damaged or resharpened probe.

In the TOOLROOM, the distinction between a height gauge and a surface gauge is that a height gauge has a measuring head (whether verner, fine rack and pinion with dial , or linear encoder with digital display), whereas a surface gauge has only a scriber point. Both are typically used on  plants and have a heavy base with an accurately flat, smooth underside.

A feasibility study of an experimental setup for the irradiation of biological samples at the cyclotron facility installed at the National Centre of Accelerators (Seville, Spain) is presented. This cyclotron, which counts on an external beam line for interdisciplinary research purposes, produces an 18 MeV proton beam, which is suitable for the irradiation of mono-layer cultures for the measurement of proton cell damages and Relative Biological Effectiveness (RBE) at energies below the beam nominal value. Measurements of this kind are of interest for proton therapy, since the variation of proton RBE at the distal edge of the Bragg curve may have implications in clinical proton therapy treatments.

. In the following, the characteristics of the beam line and the solutions implemented for the irradiation of biological samples are described. When dealing with the irradiation of cell cultures, low beam intensities and broad homogeneous irradiation fields are required, in order to assure that all the cells receive the same dose with a suitable dose rate. At the cyclotron, these constraints have been achieved by completely defocusing the beam, intercepting the beam path with tungsten scattering foils and varying the exit-window-to-sample distance. 

The properties of the proton beam thus obtained have been analysed and compared with Monte Carlo simulations. The results of this comparison, as well as the experimental measurement of the lateral dose profiles expected at the position of samples are presented. Meaningful dose rates of about 2–3 Gy/min have been obtained. Homogeneous lateral dose profiles, with maximum deviations of 5%, have been measured at a distance of approximately 50 cm in air from the exit window, placing a tungsten scattering foil of 200 μm in the beam path.