This article has multiple issues. Please help improve it or discuss these issues on the talk page . (Learn how and when to remove these template messages)
|
Four-die forging device is a special forging tool designed for manufacturing forgings with long axis by four-side radial forging method in conventional open-die hydraulic forging press. A similar stand-alone machine is known as a radial forging machine.
The device is used for deformation treatment of ingots and blanks from ordinary and high-alloy steels and alloys, including hard-to-deform ones, in wide range of shapes and grades to obtain various solid and hollow forgings, including round, square and polygonal forged bars of constant and variable cross-section, blanks of smooth and stepped shafts, axles, thick-wall pipes, mechanical tube, shells, etc.
The device consists of the upper case and the lower case with the upper die and the lower die installed therein respectively, and sliders that are kinematically interconnected with the cases by means of guides of special design and hold side dies attached thereto. The device is installed on a tool table of an open-die forging press as easy as ordinary dies. Thereat, the lower case of the device is fixed to the tool table and always remains stationary while the upper case is attached to the press ram and always travels along with it. When the press ram goes up the upper die also goes up and the side dies are retracted opening the device working space whereto a work piece is fed by a manipulator. When the press ram goes down the work piece is reduced simultaneously by four dies. Then the cycle repeats.
The second half of the 19th century was marked with the appearance of hydraulic forging presses that started to replace hammers at forging works. [1] Forging in forging presses is carried out by two dies of which one makes reciprocal movements and the other one remains stationary. This is the reason for relatively low productivity and high labour intensity of conventional forging in presses. The forging of low-ductility and hard-to-deform steels and alloys by two dies using conventional forging methods is very difficult and sometimes is practically impossible because of high tensile stresses in deformation zone leading to various forging defects and high percentage of rejected products. [2] In the 1970s the mechanical radial forging machines (RFM) started to be used for the large-scale production of long-axis forgings where a work piece is reduced in radial directions simultaneously by several pairs of dies. The process of radial forging in mechanical RFM features high productivity of forging. However small single reductions of a work piece restricted by the design of these machines lead to localization of strains mainly in surface zones of the work piece while metal in the core zone remains unworked. [3] In 80-90s hydro-mechanical and hydraulic radial forging machines appeared that do not have the disadvantages inherent to mechanical RFM. [4] [5] Nevertheless, radial forging machines are very specific and very expensive equipment in comparison with multipurpose forging presses. The application of such machines at enterprises with a wide range of forgings manufactured is economically disadvantageous and inexpedient. The problem of manufacturing long-axis forgings by radial forging method in open-die hydraulic forging presses can be solved with use of multi-die forging devices. First such devices different in design and principle of operation appeared in the 1980s. [6] [7] [8] At present, the most widespread and famous is the four-die forging device of the above described design engineered by Ukrainian and Russian scientists. The four-die forging devices have no analogues in the world now. They are successfully used at works in Russia, Ukraine, Spain, China and Germany.
The use of four-die forging devices in hydraulic forging presses provides for the following advantages in comparison with conventional methods of forging by two dies:
This article needs additional or more specific categories .(June 2024) |
Forging is a manufacturing process involving the shaping of metal using localized compressive forces. The blows are delivered with a hammer or a die. Forging is often classified according to the temperature at which it is performed: cold forging, warm forging, or hot forging. For the latter two, the metal is heated, usually in a forge. Forged parts can range in weight from less than a kilogram to hundreds of metric tons. Forging has been done by smiths for millennia; the traditional products were kitchenware, hardware, hand tools, edged weapons, cymbals, and jewellery.
Coining is a form of precision stamping in which a workpiece is subjected to a sufficiently high stress to induce plastic flow on the surface of the material. A beneficial feature is that in some metals, the plastic flow reduces surface grain size, and work hardens the surface, while the material deeper in the part retains its toughness and ductility. The term comes from the initial use of the process: manufacturing of coins.
In materials science, superplasticity is a state in which solid crystalline material is deformed well beyond its usual breaking point, usually over about 400% during tensile deformation. Such a state is usually achieved at high homologous temperature. Examples of superplastic materials are some fine-grained metals and ceramics. Other non-crystalline materials (amorphous) such as silica glass and polymers also deform similarly, but are not called superplastic, because they are not crystalline; rather, their deformation is often described as Newtonian fluid. Superplastically deformed material gets thinner in a very uniform manner, rather than forming a "neck" that leads to fracture. Also, the formation of microvoids, which is another cause of early fracture, is inhibited. Superplasticity must not be confused with superelasticity.
Metalworking is the process of shaping and reshaping metals in order to create useful objects, parts, assemblies, and large scale structures. As a term, it covers a wide and diverse range of processes, skills, and tools for producing objects on every scale: from huge ships, buildings, and bridges, down to precise engine parts and delicate jewelry.
A forming press, commonly shortened to press, is a machine tool that changes the shape of a work-piece by the application of pressure. The operator of a forming press is known as a press-tool setter, often shortened to tool-setter.
In metallurgy, a shape-memory alloy (SMA) is an alloy that can be deformed when cold but returns to its pre-deformed ("remembered") shape when heated. It is also known in other names such as memory metal, memory alloy, smart metal, smart alloy, and muscle wire. The "memorized geometry" can be modified by fixating the desired geometry and subjecting it to a thermal treatment, for example a wire can be taught to memorize the shape of a coil spring.
Extrusion is a process used to create objects of a fixed cross-sectional profile by pushing material through a die of the desired cross-section. Its two main advantages over other manufacturing processes are its ability to create very complex cross-sections; and to work materials that are brittle, because the material encounters only compressive and shear stresses. It also creates excellent surface finish and gives considerable freedom of form in the design process.
Hydroforming is a means of shaping ductile metals such as aluminium, brass, low alloy steel, and stainless steel into lightweight, structurally stiff and strong pieces. One of the largest applications of cost-effective hydroforming is the automotive industry, which makes use of the complex shapes made possible by hydroforming to produce stronger, lighter, and more rigid unibody structures for vehicles. This technique is particularly popular with the high-end sports car industry and is also frequently employed in the shaping of aluminium tubes for bicycle frames.
In physics, mechanics and engineering, an adiabatic shear band is one of the many mechanisms of failure that occur in metals and other materials that are deformed at a high rate in processes such as metal forming, machining and ballistic impact. Adiabatic shear bands are usually very narrow bands, typically 5-500 μm wide and consisting of highly sheared material. Adiabatic is a thermodynamic term meaning an absence of heat transfer – the heat produced is retained in the zone where it is created.
In metalworking, rolling is a metal forming process in which metal stock is passed through one or more pairs of rolls to reduce the thickness, to make the thickness uniform, and/or to impart a desired mechanical property. The concept is similar to the rolling of dough. Rolling is classified according to the temperature of the metal rolled. If the temperature of the metal is above its recrystallization temperature, then the process is known as hot rolling. If the temperature of the metal is below its recrystallization temperature, the process is known as cold rolling. In terms of usage, hot rolling processes more tonnage than any other manufacturing process, and cold rolling processes the most tonnage out of all cold working processes. Roll stands holding pairs of rolls are grouped together into rolling mills that can quickly process metal, typically steel, into products such as structural steel, bar stock, and rails. Most steel mills have rolling mill divisions that convert the semi-finished casting products into finished products.
Magnesium wheels are wheels manufactured from alloys which contain mostly magnesium. Magnesium wheels are produced either by casting (metalworking), or by forging. Magnesium has several key properties that make it an attractive base metal for wheels: lightness; a high damping capacity; and a high specific strength. Magnesium is the lightest metallic structural material available. It is 1.5 times less dense than aluminium, so magnesium wheels can be designed to be significantly lighter than aluminium alloy wheels, while exhibiting comparable strength. Many competitive racing wheels are made of magnesium alloy.
Magnesium alloys are mixtures of magnesium with other metals, often aluminium, zinc, manganese, silicon, copper, rare earths and zirconium. Magnesium alloys have a hexagonal lattice structure, which affects the fundamental properties of these alloys. Plastic deformation of the hexagonal lattice is more complicated than in cubic latticed metals like aluminium, copper and steel; therefore, magnesium alloys are typically used as cast alloys, but research of wrought alloys has been more extensive since 2003. Cast magnesium alloys are used for many components of modern automobiles and have been used in some high-performance vehicles; die-cast magnesium is also used for camera bodies and components in lenses.
Deep drawing is a sheet metal forming process in which a sheet metal blank is radially drawn into a forming die by the mechanical action of a punch. It is thus a shape transformation process with material retention. The process is considered "deep" drawing when the depth of the drawn part exceeds its diameter. This is achieved by redrawing the part through a series of dies.
A riveting machine is used to automatically set (squeeze) rivets in order to join materials together. The riveting machine offers greater consistency, productivity, and lower cost when compared to manual riveting.
Equal channel angular extrusion (ECAE) called also equal channel angular pressing (ECAP) is one technique from the Severe Plastic Deformation (SPD) group, aimed at producing Ultra Fine Grained (UFG) material. Developed in the Soviet Union in 1973 by Segal. However, the dates are not always consistent. In industrial metalworking, it is an extrusion process, The technique is able to refine the microstructure of metals and alloys, thereby improving their strength according to the Hall-Petch relationship. This process improves not only the strength but also other properties such as corrosion and wear resistance of alloys and compounds.
Shear forming, also referred as shear spinning, is similar to metal spinning. In shear spinning the area of the final piece is approximately equal to that of the flat sheet metal blank. The wall thickness is maintained by controlling the gap between the roller and the mandrel. In shear forming a reduction of the wall thickness occurs.
Kamensk-Uralsky Metallurgical Works J.S.Co. (KUMZ) is one of the town-forming enterprises of Kamensk-Uralsky, Sverdlovsk Oblast, Russia. KUMZ was founded especially for supplying of aerospace industry with semi-finished products in aluminium and magnesium alloys. Currently, the plant produces aluminium alloy billets, forged and rolled plates, roll bond heat exchangers, extruded rods, bars, tubes, drill pipes, profiles, die-forgings.
Uddeholms AB is a multinational producer of high alloyed tool steel with production in Hagfors, Sweden. Since 1991, the company is part of the Austrian Böhler-Uddeholm group which in turn is part of the voestalpine AG group since 2007. Uddeholms AB has 800 Swedish and 3,000 total employees.
In metalworking, forming is the fashioning of metal parts and objects through mechanical deformation; the workpiece is reshaped without adding or removing material, and its mass remains unchanged. Forming operates on the materials science principle of plastic deformation, where the physical shape of a material is permanently deformed.
Rule based DFM analysis for forging is the controlled deformation of metal into a specific shape by compressive forces. The forging process goes back to 8000 B.C. and evolved from the manual art of simple blacksmithing. Then as now, a series of compressive hammer blows performs the shaping or forging of the part. Modern forging uses machine driven impact hammers or presses that deforms the work-piece by controlled pressure.