Magnetron generated waves produce an alternating magnetic field, and food molecules, especially polar molecules, such as water, proteins, and fats, align themselves with the rapid changes in the alternating electric field. They swing around an axis that is about 245 million times a second. These fluctuations cause significant friction between the molecules and, as a result, generate energy. As a result of this, the food is heated, while the food is cool. Ease of use and low baking time have led to the use of this product in homes and restaurants. Further explanations on how microwave work: microwave ovens like radio waves and radio waves are a kind of electromagnetic energy. These waves are in fact very short wavelengths of electromagnetic energy traveling at the speed of light. From these waves, radio, television programs Computer information and telephone signals are used. But this word has in our mind the concept of a cooking machine. Microwave transmissions have an effect on food molecules, and with each cycle, a pulsed wave of molecular molecules from Positive to negative. In the microwave oven, these polarization changes occur millions of times per second. Some food molecules, especially water molecules, have two positive and negative endpoints, just as they are a North and South Dipole Ribadara. Microwave beams bombard the cooking molecules and convert them to polar molecules that change poles every second with the same frequency of millions of times. All of these stimuli, causing friction, also cause serious damage, such as disrupting or disposing of surrounding cells, which are known as structural isomyric science. There are numerous references to the description of electromagnetic waves, one of which is radioactive radioactivity Or the distribution of energy with electromagnetic waves. Radioactive radioactivity on its physical expression is ((emitting electromagnetic waves from atoms or molecules of radioactive materials following the destruction of their nuclei.) This irradiation causes ionization, and ionization occurs when a neutral electron is received Slow or loses. Simply put, a microwave oven through the process of radiation, by electromagnetic radiation, destroys or modifies the nutrition molecules. If the manufacturers of this device were using their exact name (or radioactive oven) They were not even able to sell even one of them. But this is precisely what we call microwave. We are told that microwave cooking is different with radiotherapy or radiation therapy. No study has been approved by the US government and no harm has been done so far, but we know well that the credibility of studies and research can be limited and sometimes these studies are not deliberately performed, and we The consumer title should be used to judge to a degree from our senses.
The application of polymer materials in the automotive industry is also synchronous, and sometimes more than other industries. In the automotive industry, it is worth noting that the reduction in weight due to the replacement of polymer parts rather than metal parts leads to a reduction in fuel consumption, which, in addition to saving Economics is effective in protecting energy and environmental resources. One of the aspects that researchers are concerned about using polymer materials in the industry is the issue of recycling. The importance of corrosion resistance and generally good resistance to environmental conditions of this material group Arises.
Chairs (foam, cloth and other non-polymeric components), felt, carpet, rubber rug, dashboard, heater, false ceilings, trowels, tire, insulators, washers, adhesives, fasteners, fittings, over-rings, wires, electrical parts, shields and . . . Examples are the application of polymer in the car.
It is estimated that plastics will provide 10% of the weight of new cars, and this is rising. (1) Different parts of the car have the ability to make composites. Including: body (roof frame and pickup room), chassis (connecting bars and front diagonal members), power transmission system (carriage bars and water pump compartment), and internal parts (car jack, steering wheel, window frames and seats ) (2)
What is polymer?
The polymer consists of a combination of the two mer and poly words. The term “poly” is a prefix, meaning “few” and “cease” and “mer” means “torn.” The mono-mer mono-mer is a mono-pit. Polymer or polymer is actually obtained by the addition of a large number of monomers to each other. For example, polyethylene comes from the pooling of a large number of methane molecules. Methane (gas Natural) consists of a carbon atom and four hydrogen atoms and is written in the form of 4CH. However, if a large number of these molecules (about 1800) are sequentially bonded together, a polymeric or large chain The molecule is formed: ~~~~ CH4-CH4-CH4-CHA-CH4- … -CH4 ~~~~
Here, CH4 is a monomer or monomer. That is, the smallest component, with its repeated, polymer chains. A set of these chains generates a polymer called polyethylene which is used in various products, such as various plastic bags. Indeed, the difference between the polymer and other materials is that it consists of large molecules, and other materials, such as water, metals, etc., are composed of molecules and atoms that are separate, that is, the formation of large molecules.
Here is a brief definition of some types of polymers.
Rubber: An important feature of rubber parts is that they are flexible and have elasticity and reversibility. Rubber parts are usually not usable alone. But they are cooking with the addition of sulfur as a result of heat. That is, the sulfur interconnects the chains and brings it into network mode. Crude fiber is actually a plastic. It can be melting or in any form. But it does not melt due to baking or grating, and it resists deformation. The cooked rubber is elastomer. The characteristic of elastomer is that under a relatively low force They can be pulled up to 100% of their initial length without breaking, and returning to the original length with the removal of force.
Plastic (plastic): Plastics can be melted by heat in a variety of shapes. Plastics are divided into two major groups. A bunch of them are thermo plastic, which means they can melt in the heat. Like many polymer containers. The other bundles are the ones that are in the form of a network, such as a power outlet and melamine containers. Tungsten can take many shapes before the final state, but after applying heat and pressure, they can not melt.
Composite (composite) is obtained by combining a polymer component with another component (such as glass fiber), such as fiberglass pieces.
Foam: Foam is called foam when it is made of porous rubber or plastic in a way that is very light (e.g., 5 pounds of water, about 50 Kg / m3).
Adhesive: The polymers can be in such a way that they can interconnect two materials together, either physically or chemically. For example, PVC has the ability to either glue or piecewise Rigid and hard.
Fiber (Fiber): Polymers can be made with a low cross-sectional length, which in this case are called fibers.
An alloy (blend) is obtained from the combination of two or more polymers with each other. Its component with composite is that all components of the polymer are alloys in the alloy, but in the composite the other component can not be polymer, for example, glass fiber. Another fiber In general, the components are separated in the composite and can be seen with the naked eye of both components, but in the alloy components are interconnected in such a way that they can not be separated by the naked eye.
Copolymer: When at least two types of polymers are combined in the same way in which the chains or monomer are bonded together, a copolymer is formed. Polymer is also called homopolymer.
To get the cylindrical shape, the workpiece moves through the machine around its own axis (turning axis). During the workpiece, it works with the winning tool that is closed against it and to remove it from it. . This way of doing the job is called a “wheel”, and the work requires several different moves.
The various forms of turning parts are achieved through a series of different tasks, and the parts are shaved from outside or inside. In brief, they are:
(Turning out) or turning (inside).
The cylindrical parts are made through a continuous cutting (smooth surfaces), through a shear, cone parts through a cone, and finally, molded parts are made through a molding and screws through a twisting.
In order to solve the problem of turning issues and to be able to toggle different types of work, CNC machines are made of different types. The most commonly used machines are the same as conventional milling or bite cutting. And other important types are the carving machine and the vertical machine or carousel, which also performs drilling operations.
This device is used to support the long piece of work and, in addition, during hole or welding, the winning tool is mounted by the cone trail that it is mounted on. The birdie machine can be moved to the paddle and tightened at any desired point. To move its inner bar from the bird’s end gear, it is used to keep the front of the front lever fixed.
It carries all parts and lathe pieces and moves on supports, supports and accessories as well as a birdie on the desk guides. These guides often have a prism shape and may also be flat to cut diamonds The big ones have made a part of the machine table so that it can be removed.
Gearbox for main move:
The work rod during the cutting of the parts must have a different period relative to the working conditions and specifications (round is the number of workpieces per minute). To obtain a different period, a device called the master gear box is usually used Instead, it is located beneath the machine’s bearings. Sometimes a part of the gearbox may be embedded inside the car’s base. By moving the belt and the gear, the number of turns can be changed in the step of the mine (intermediate), for example, from 105 to 151 and 214 rounds per minute. In addition to the gearboxes, it is possible that by their number of rounds Except in the form of a mineral step (intermediate).
To cut off the cutting tools, they use turning joints and turning brushes. The power of doing things tools is related to the gender and the form of the edge of the winning tool.
Material of turning tools:
The instrumentation shall have the following properties:
Hardness, resistance, hardness resistance to heat and resistance to wear. The tool’s stitch must be hard so that its winning edge can penetrate inside the work, and if it does not have enough resistance, the winning edge breaks apart, and each tool must be somewhat It can withstand the heat generated by its frictional edge by winning it, and maintain its hardness, and it must have a special resistance to wear and tear, so that it does not quickly disappear from work and does not slip.
For turning tools, different sexes are used:
Non-alloy steel: A steel with 0.5 to 1.5% carbon. This steel loses its hardness in the heat of 250 ° C and is therefore not suitable for cutting speeds. In the same way, this steel In exceptional cases, they are only used to make turning joints. Often, steel is referred to as non-alloy tool called carbon steel and as simple as steel tool (ws).
Alloyed steel: steel other than its alloys carbon, including alloys, worms, vanadium, molybdenum and the like. Alloyed castings may also have low and high percentages of their alloys, for example, stearic acid (ss), high alloying percentages And its resistance to erosion is also very high. It keeps its hardness up to 600 ° C. The hardness property of this steel is more than anything else owed to the heat, and due to the same property, it can be operated with very high cutting speeds. Because the price of steel is high, often only the winning part of the tool or sheet You install and weld this steel on a machine-made steel carving body.
Hard metals: The power of doing work greatly increases the tool. The main component of the compound substance is hard metal and lobram or molybdenum. There are also some cobalt and carbon in it. The hard metal is very expensive, and therefore the softened blades are soldered to a winner of constructional steels.
The shearing power of a hard-grinding steel grinding machine is 900 ° C, so it can be used in a very long period of time, and with these properties, the time of working with these steel is shorter, resulting in The cutting speed of the workpiece is very smooth and clean. To perform work on different types of turning operations, it is necessary to use a hard metal type suitable for them.
Grizzly Diamonds: Diamonds are often used instead of the edge of the winning tool, their gender is very hard and their resistance to wear is immensely good. Grab the diamonds, especially for the smoothness of the parts on the car
When milling is done by rotating a blade blade, whose edges are wound on the circular environments, cutting and removing the cutters are also used. The milling blade is also called the multi-edge tool, and the blade rods are shaped into the workpiece (Such as a grinder). The rotary blade rotational movement is called the main motion or the cutting. To create the thickness of the cutting, the work has a direct linear motion or so-called load motion. The main movement and loading are done by milling. During the milling of each milling blade gear, they only scrape for a short time during their turning and, until they come to the next, they are free to circulate and cool without being cut, so this tool, like a grinder, does not come under permanent pressure due to cutting.
Milling by the body or the front of the milling blade (milling roller and simple milling blade):
When cutting a piece with a milling roller, the blade axis is located parallel to the work surface. The milling rod has a roller form and with the edges that are in its corners, it separates from the cutting unit and the cuttings cut out form (woW). In milling machine with blade forehead, milling blade blades are perpendicular to the working axis. In this case, the milling blade does not work only with the teeth of its environment, but the section of the teeth, which is the same as the forehead milling, also work, and the cuttings taken are of a uniform thickness.
Correction of cut with body and cut with forehead milling:
When the blade blade is removed because it has uneven thickness, the pressure on the milling machine is not uniform and, therefore, if the lamellar blade has a small perimeter, it will not be easy to prevent it. This lame makes it possible on the surface of the milling The work for each blade circle will play a wave sign (milling tongue). But when it comes to cutting the forehead, as it has been mentioned before, the overall thickness of the blade is uniform, and therefore the pressure on the machine will be uniform, and as a result The power of cutting a car is generally about 15% to 20% more than the previous one And if the cutting blade has a slight lamina, then there is no effect on the smooth surface of the carved surface, and therefore the surfaces will be smoother than the blade with the blade body. It is therefore recommended that even smooth surfaces Work in this way.
Merging with moving and reverse:
In the milling of the roller or with the body of the blade, the movement of the load is adjusted to the opposite direction of the milling blade, but it is possible that the direction of the load also accompanies the direction of the blade movement. In the first way, the direction of the blade and the work is not the same and most work with The roller bolt blade is in this state. The scraper is first cut off from the thinner end, and before the blades of the milling blade penetrate into the interior, it is applied to the work surface, and so a lot of friction is generated and the cutting force tries to get the workpiece up Pull it
In another way, the movement of the load in the same direction as the blade blade is done, in contrast to the previous state, the win-winches of the blade take the thickest starting point, and because of this, the workpiece is firmly attached to its support, this way is used to mold the thin pieces. In addition, this There is also a way to apply a deep cut depth, but it should be considered that the construction of the car is subject to such work (in order to move the load with the direction of the milling blade). The point to be followed before is that The molding of the table should not be slipped, because in the bottom If this is the case, the workpiece is pulled to the cutting blade.
Types of milling machines and their building:
The shape and magnitude of the milling parts in terms of economic considerations requires that the milling machines have different types of construction:
Horizontal milling machine:
The machine is used almost to do all the usual milling tasks, and hence the name of the horizontal mill has given it the milling desire to be horizontally bearing.
The body of the car carrying this milling mill, which is a horizontal bearing, with the main loading and loading device, as well as the bench seat with a transversal drawer and milling table and its other accessories.
The milling thread is usually stable on the shaft or slider bearings, and to make it work perfectly without flickering, the milling mill size is chosen sufficiently large. For tightening the milling tools, the milling head has an inner cone and an outer cone.
The main motion machine is the same as the original movement, which is the same as the original motion, and the machine’s displacement is variable in order for the milling blade to be suitable for correct cutting speed. Old cars have a bridging machine, but modern machines work with a flatbed engine, and with the help of a box and lever it may work at 12 different speeds or more.
The machine tightens the piece of work on the milling table and, in order to pass the work from the front of the cutter, the cutter’s cutter is movable in the direction of the height and the transverse drawer in the transverse direction and the desk bench in the longitudinal direction, in order to move the twisted bolts They come in handy wheels, and the car can be moved by the loader. This movement is carried out directly by the motor, either directly or indirectly, by the motor, and can be fitted with a movable hammer or transaxle box device. Different loading speeds can be used. To connect the machine, The barbed wire and a snail device are used and the length of the load may be limited by a specific bundle suitable for work.
Large milling machines often come with fast-moving gears
Reverse engineering, also called back engineering, is the processes of extracting knowledge or design information from anything man-made and reproducing it or reproducing anything based on the extracted information. The process often involves disassembling something (a mechanical device, electronic component, computer program, or biological, chemical, or organic matter) and analyzing its components and workings in detail.
The reasons and goals for obtaining such information vary widely from everyday or socially beneficial actions, to criminal actions, depending upon the situation. Often no intellectual property rights are breached, such as when a person or business cannot recollect how something was done, or what something does, and needs to reverse engineer it to work it out for themselves. Reverse engineering is also beneficial in crime prevention, where suspected malware is reverse engineered to understand what it does, and how to detect and remove it, and to allow computers and devices to work together (“interoperate”) and to allow saved files on obsolete systems to be used in newer systems. By contrast, reverse engineering can also be used to “crack” software and media to remove their copy protection, or to create a (possibly improved) copy or even a knockoff; this is usually the goal of a competitor.
Reverse engineering has its origins in the analysis of hardware for commercial or military advantage. However, the reverse engineering process in itself is not concerned with creating a copy or changing the artifact in some way; it is only an analysis in order to deduce design features from products with little or no additional knowledge about the procedures involved in their original production. In some cases, the goal of the reverse engineering process can simply be a redocumentation of legacy systems. Even when the product reverse engineered is that of a competitor, the goal may not be to copy them, but to perform competitor analysis. Reverse engineering may also be used to create interoperable products; despite some narrowly tailored US and EU legislation, the legality of using specific reverse engineering techniques for this purpose has been hotly contested in courts worldwide for more than two decades.
Bakelite or polyoxybenzylmethylenglycolanhydride, is an early plastic. It is a thermosetting phenol formaldehyde resin, formed from a condensation reaction of phenol with formaldehyde. It was developed by the Belgian-American chemist Leo Baekeland in Yonkers, New York, in 1907.
One of the first plastics made from synthetic components, Bakelite was used for its electrical nonconductivity and heat-resistant properties in electrical insulators, radio and telephone casings and such diverse products as kitchenware, jewelry, pipe stems, children’s toys, and firearms. The “retro” appeal of old Bakelite products has made them collectible.
Bakelite was designated a National Historic Chemical Landmark on November 9, 1993, by the American Chemical Society in recognition of its significance as the world’s first synthetic plastic.
Baekeland was already wealthy, due to his invention of Velox photographic paper, when he began to investigate the reactions of phenol and formaldehyde in his home laboratory. Chemists had begun to recognize that many natural resins and fibres were polymers. Baekeland’s initial intent was to find a replacement for shellac, a material that was in limited supply because it was made naturally from the excretion of lac insects (specifically Kerria lacca). Baekeland produced a soluble phenol-formaldehyde shellac called “Novolak”, but it was not a market success.
Baekeland then began experimenting to strengthen wood by impregnating it with a synthetic resin, rather than coating it. By controlling the pressure and temperature applied to phenol and formaldehyde, Baekeland produced a hard moldable material which he named “Bakelite”. It was the first synthetic thermosetting plastic ever produced, and Baekeland speculated on “the thousand and one … articles” that it could be used to make.:58–۵۹ Baekeland considered the possibilities of using a wide variety of filling materials, including cotton, powdered bronze, and slate dust, but was most successful with wood and asbestos fibers.
Baekeland filed a substantial number of patents in the area. His “Method of making insoluble products of phenol and formaldehyde” was filed on July 13, 1907, and granted on December 7, 1909. Baekeland also filed for patent protection in other countries, including Belgium, Canada, Denmark, Hungary, Japan, Mexico, Russia, and Spain. He announced his invention at a meeting of the American Chemical Society on February 5, 1909.