What is metalworking
What is metalworking?
Metal working (metal work, metal processing, working of metals) is referred to as metalworking, which refers to the production activities of human beings to process metal elements or materials with metal characteristics mainly composed of metal elements. It is a process technology for processing metal materials into articles, parts and components, including large parts of bridges, ships and even fine components of engines, jewelry and watches. It is widely used in science, industry, art, handicrafts and other different fields.
The progress of human society is closely related to the processing and application of metal materials. Brass was smelted more than 6000 years ago, simple bronze tools were made more than 4000 years ago, and meteorite iron was used to make weapons more than 3000 years ago. China was able to smelt pig iron in the spring and Autumn Period more than 2500 years ago, more than 1800 years earlier than Europe. In the 18th century, the development of iron and steel industry has become an important content and material basis of industrial revolution.
History of metal processing
From 1 million years ago, primitive people used stones as tools, known as the Paleolithic age. 10000 years ago, human beings processed stone tools into utensils and exquisite tools, thus entering the Neolithic age. Archaeological excavations have proved that practical pottery was made in China more than 8000 years ago, brass was smelted more than 6000 years ago, simple bronze tools were made more than 4000 years ago, and meteorite iron was used to make weapons more than 3000 years ago. Our ancestors were able to smelt pig iron in the spring and Autumn period more than 2500 years ago, more than 1800 years earlier than in Europe.
In the 18th century, the development of iron and steel industry has become an important content and material basis of industrial revolution. In the mid-19th century, with the emergence of modern open hearth and converter nickel tube steelmaking technology, mankind really entered the iron and steel era. At the same time, copper, lead and zinc have also been widely used, and aluminum, magnesium, titanium and other metals have come out and been used one after another. Metal materials have always occupied a leading position in the material industry. Metal material can be said to be the witness of the whole process of human social development. The reason why it is said is inseparable from its pivotal role in various transition periods of human society. As a kind of material first discovered and used by human beings, metal can affect the historical development process of human beings in all aspects. From the initial making of metal into hunting weapons to now, human life has been completely inseparable from metal. It can be seen that metal has already been integrated into the whole human society. What will metal be like in the past and future of human society.
The role of metal in the past tense of human society is mostly the epitome of the social nature of a period. For example, the Neolithic age, the bronze age and so on. In the final analysis, the main reason for naming these ages is that human beings have developed a new metal in this stone age, and this metal almost determines the development process of human civilization in this period.
For example, in the Warring States period, the invention and use of iron tools not only liberated a large number of rural productive forces, but also greatly shortened the process of war after being put into use in the war, thus accelerating the unification of the whole country and ending the chaotic situation, so that China’s civilization can continue to develop normally after a period of turbulence. Among them, the contribution of metal in weapons is mainly in the casting of cold weapons, especially stone weapons and bronze weapons. The stone weapon period lasted about five or six million years from the primitive people learned to make labor tools – stone axe and stone knife to the advent of bronze weapons in the Xia Dynasty.
Judging from the unearthed stone weapons, the oldest weapons in China were made by ancient ape men who collected quartz stone, sandstone, brilliant stone and other raw materials and beat and ground them. There are various irregular shapes such as flat, round, square and closed, some with knives and some in school shape. Our ancestors relied on those instruments that were both labor tools and defense weapons to surround animals, hunt, slash and burn, survive tenaciously and evolve. By the end of the Paleolithic age, people had been able to manufacture stone spears, javelins, stone axes and other weapons that could be installed with bamboo barrels, and then invented the throwing weapon – bow and arrow. This fully shows the wisdom and skills of the working people in ancient China. People bid farewell to ignorance and move towards civilization. In the Neolithic age, the manufacturing technology of stone weapons has made great progress, and the types are increasing day by day. The bronze weapon period lasted from the Xia Dynasty to the spring and Autumn period and the Warring States period. During this period, with China’s slavery society, it went from prosperity to decline. With the increasing prosperity of bronze culture in the Shang Dynasty, bronze weapons rose rapidly and soon became a tool mastered by the slave owner aristocratic literati class. They completely replaced the ancient stone weapons and became the main weapons equipped in the army in the era of vehicle warfare. Therefore, it can be seen that metal materials played an important role in ancient society. After people realized this, they also increased the scope of utilization, which also promoted the development of metal smelting technology to a certain extent. The two complement each other.
Metal processing technology
Metal processing refers to the production activities of human beings to process materials with metal characteristics composed of metal elements or mainly metal elements. Metal processing methods and processes include:
Casting: it refers to that the metal is heated and melted, and then poured into the model, which is suitable for processing complex parts.
Sand casting: with low cost and small batch, it can process complex shapes, but it may require a large number of post-treatment processes.
Investment casting/wax loss casting: this processing method has high continuity and accuracy, and can also be used to process complex shapes. On the premise of relatively low processing cost, it can achieve very surface effect and is suitable for mass production.
Injection casting method: used to process complex modeling with high error. Due to the characteristics of the process itself, the product does not need post-treatment after forming. However, it can show the advantage of low cost only in the case of mass production.
Die casting method: the processing cost is high, and the cost is reasonable only in the case of mass production. However, the cost of the final product is relatively low and the error is relatively high. It can be used to produce parts with thin wall thickness.
Rotary casting method: it is an ideal method for processing small parts. It is usually used in jewelry manufacturing. Rubber models can be used to reduce processing costs.
Directional solidification: it can produce very strong super heat resistant alloy with excellent fatigue resistance, pour it into the model, and then go through strictly controlled heating and cooling processes to eliminate any small defects. Plastic forming processing part of plastic forming processing: it refers to high-temperature heating of formed metal for re molding, which is a labor-intensive production.
Plastic forming processing
Forging: under the condition of cold working or high-temperature operation, metal is shaped by hammering and extrusion. It is one of the simplest and oldest metal molding processes.
Binding: the high-temperature metal billet passes through several continuous cylindrical rollers, which tie the metal into the mold to obtain the preset shape.
Wire drawing: the process of drawing a metal strip into a fine wire shape by using a series of wire drawing dies with gradually smaller specifications.
Extrusion: a low-cost process for continuous processing, solid or hollow metal molding with the same cross-section shape, which can be used for high-temperature operation and cold processing.
Impact extrusion: a process used to process small to medium-sized parts without taper requirements. The production is fast, the parts with various wall thicknesses can be processed, and the processing cost is low.
Powder metallurgy: a process that can process ferrous and nonferrous metal components. It includes two basic processes: mixing alloy powder and pressing the mixture into the mold. Metal particles are formed by high temperature heating and sintering. This process does not need machining, and the utilization rate of raw materials can reach 97%. Different metal powders can be used to fill different parts of the mold.
Solid forming processing
Solid molding processing: refers to the raw materials used are some metal strips, sheets and other solid forms that can be molded at room temperature. It belongs to labor-intensive production. The processing cost can be relatively low.
Classification of solid forming processing
Spinning: a very common processing method used to produce circular symmetrical parts, such as plates, cups and cones. During machining, the high-speed rotating metal plate is pushed into the model on the same high-speed rotating and fixed lathe to obtain the preset shape. The process is suitable for various batch forms of production.
Bending: an economical production process for processing any form of sheet, rod and tubular materials.
Continuous binding forming: the metal sheet is fed between the pressing rollers to obtain a metal shape with continuous length and consistent cross section. It is similar to the extrusion process, but there are restrictions on the wall thickness of processing components, and only a single wall thickness can be obtained. Only under the premise of mass production, the processing cost is the most reasonable.
Stamping forming: the metal sheet is placed between the male mold and the female mold for pressing and forming, which is used for processing hollow modeling, and the depth can be deep or shallow.
Punching: the process of punching and cutting a certain shape on a metal sheet with special tools, which can be applied to large and small batch production.
Punching: it is basically similar to the punching process, except that the former uses the punching part, while the latter uses the remaining part of the metal sheet after punching.
Cutting: cutting sheet metal by cutting is the same as cutting paper from the best position with a pair of scissors.
Chip forming: when cutting metal, the cutting methods with chip production are collectively referred to as chip forming, including milling, drilling, lathe processing, grinding, sawing and other processes.
Chip free forming: using existing metal strips or metal sheets for modeling. No chips are generated. Such processes include chemical processing, corrosion, EDM, sand blasting, laser cutting, water jet cutting and thermal cutting.
Wire drawing can be made into straight lines, random lines, threads, ripples and spiral lines according to decorative needs.
Straight line wire drawing refers to machining straight lines on the surface of aluminum plate by mechanical friction. It has the dual functions of brushing off the scratches on the surface of aluminum plate and decorating the surface of aluminum plate. There are two kinds of straight wire drawing: continuous wire drawing and intermittent wire drawing. Continuous wire drawing can be obtained by continuous horizontal linear friction on the surface of aluminum plate with cleaning cloth or stainless steel brush (such as manual technical grinding under the condition of existing device or grinding on aluminum plate with steel wire brush clamped by planer). By changing the steel wire diameter of the stainless steel brush, lines of different thickness can be obtained. Intermittent silk lines are generally processed on a polishing machine or a texturing machine.
Preparation principle: two groups of differential wheels rotating in the same direction are adopted. The upper group is a fast rotating grinding roller and the lower group is a slow rotating rubber roller. Aluminum or aluminum alloy plate passes through the two groups of rollers and is brushed with fine intermittent straight lines.
Random wire drawing is a kind of irregular matte wire pattern without obvious lines obtained by moving and rubbing the aluminum plate back and forth, left and right under the high-speed copper wire brush. This processing has high requirements for the surface of aluminum or aluminum alloy plate.
Corrugations are generally made on a brushing machine or a texturing machine. Using the axial movement of the upper group of grinding rollers, grind and brush on the surface of aluminum or aluminum alloy plate to obtain wavy lines.
Rotary pattern, also known as optical rotation, is a kind of silk pattern obtained by rotating and polishing the surface of aluminum or aluminum alloy plate with cylindrical felt or stone grinding nylon wheel installed on the drilling machine and kerosene mixed with polishing paste. It is mostly used for decorative processing of circular signs and small decorative dials.
The thread is fixed on the table by a small motor equipped with circular felt on the shaft at an angle of about 60 degrees with the edge of the table. In addition, a carriage equipped with fixed aluminum plate for pressing tea is made, and a polyester film with straight edge is pasted on the carriage to limit the thread competition. The rotation of the felt and the linear movement of the carriage are used to spin and wipe the thread pattern with the same width on the surface of the aluminum plate.
The characteristics of plastic electroplating plastic electroplating products have the characteristics of both plastic and metal. It has small specific gravity, good corrosion resistance, simple forming, metallic luster and metallic texture, as well as conductivity, magnetic conductivity and welding. It can save complicated machining processes and metal materials, and is beautiful and decorative. At the same time, it also improves the mechanical strength of plastic products. Because the metal coating has high stability to external factors such as light and atmosphere, the plastic aging can be prevented and the service life of plastic parts can be prolonged after metal plating. With the rapid development of industry and the increasing application of plastic electroplating, it has become one of the important means of surface decoration in plastic products. Electroplating has been widely carried out on the surfaces of ABS, polypropylene, polysulfone, polycarbonate, nylon, phenolic glass fiber reinforced plastics, polystyrene and other plastics at home and abroad, especially ABS plastic electroplating is the most widely used and the electroplating effect is the best.
Source: China Flange Manufacturer – Yaang Pipe Industry (www.steeljrv.com)
(Yaang Pipe Industry is a leading manufacturer and supplier of nickel alloy and stainless steel products, including Super Duplex Stainless Steel Flanges, Stainless Steel Flanges, Stainless Steel Pipe Fittings, Stainless Steel Pipe. Yaang products are widely used in Shipbuilding, Nuclear power, Marine engineering, Petroleum, Chemical, Mining, Sewage treatment, Natural gas and Pressure vessels and other industries.)
If you want to have more information about the article or you want to share your opinion with us, contact us at email@example.com
Please notice that you might be interested in the other technical articles we’ve published: