What about forgings, castings, machined parts, components, and pipe fittings?

Forgings are produced through forging, and their quality is higher than that of castings； Castings are formed through casting, and their shapes can vary widely ； Machined parts are produced using machining equipment such as machine tools ； Components: The various parts that make up mechanical equipment are referred to as components; mechanical equipment is composed of such components ； Fittings are components that make up piping systems, such as flanges, elbows, tees, etc.

1. Forgings: Forgings are objects made of metal to which pressure is applied, resulting in plastic deformation that gives them the desired shape or appropriate strength. This force is typically achieved by using a hammer or pressure. The casting process creates a fine granular structure and improves the physical properties of the metal. In the actual use of components, a proper design can ensure that the particle flow moves in the direction of the main pressure. 　　Each forging piece must be uniform, with no porosity, excess space, inclusions, or any other defects. Components produced by this method have a high strength-to-weight ratio. These components are typically used in aircraft structures. 　　The advantages of forgings include an extendable length and a reducible cross-section ； Contractible length, expandable cross-section ； Variable length, variable cross-section. The types of forgings include: free forging/hand forging, hot die forging/precision forging, upset forging, roll forging, and die forging. 2. Castings: Metal objects obtained through casting methods, that is, molten metal is poured into a pre-prepared mold using pouring, injection, suction, or other methods; after cooling, the object undergoes sand removal, cleaning, and post-treatment to acquire a specific shape, size, and properties. There are various ways to classify castings: based on the metal materials used, they can be divided into cast steel, cast iron, cast copper, cast aluminum, cast magnesium, cast zinc, cast titanium, and so on. And each type of casting can be further divided into different categories based on its chemical composition or microstructure. Cast iron products can be classified into gray cast iron, ductile iron, nodular iron, malleable cast iron, alloy cast iron, etc ； Based on the different casting methods, castings can be classified into ordinary sand castings, die castings, die-cast products, centrifugally cast parts, continuously poured components, investment castings, ceramic mold castings, electroslag remelted castings, bimetallic castings, and so on. Among them, ordinary sand castings are the most widely used, accounting for about 80% of the total cast output. Non-ferrous metal castings such as aluminum, magnesium, and zinc are mostly die-cast products. Castings possess excellent mechanical and physical properties; they can have a variety of comprehensive properties involving different levels of strength, hardness, and toughness. They may also exhibit one or more special properties, such as wear resistance, resistance to high and low temperatures, and corrosion resistance. 　　The weight and dimensions of castings vary widely: the lightest ones weigh only a few grams, while the heaviest can reach 400 tons. The thinnest wall thickness is 0.5 millimeters, while the thickest can exceed 1 meter. The length can range from a few millimeters to over ten meters, allowing them to meet the requirements of different industrial sectors. 3. Machined parts, components, and pipe fittings are a general term; experts are invited to provide a more specific definition.

Forgings can be classified by their intended use into: aircraft forgings, diesel engine forgings, marine forgings, military weapon forgings, petrochemical industry forgings, mining industry forgings, nuclear power industry forgings, thermal power industry forgings, and hydropower industry forgings. Due to various factors, castings often suffer from defects such as pores, pinholes, slag inclusions, cracks, and pits. Difference between forgings and castings: Generally speaking, the mechanical properties of castings are lower than those of forgings made from the same material. Furthermore, forging processes ensure the continuity of the metal fiber structure, allowing the fiber pattern in the forged part to match its shape; the metal flow lines remain intact, which ensures that the parts possess excellent mechanical properties and a long service life. Forged parts produced using techniques such as precision die forging, cold extrusion, and warm extrusion are incomparable to cast parts. Forgings have good mechanical properties due to their uniform, fine, and dense microstructure with few defects. Castings, on the other hand, may have numerous defects such as shrinkage cavities, porosity, gas holes, inclusions, as well as casting stresses, all of which can reduce their performance. The definition of mechanical parts is as follows: 1. Part – a single component that cannot be separated. 2. Components — a combination of parts that enables a certain action (or function). A component can be a single part or a combination of multiple parts. In this assembly, there is one main component that carries out the specified action (or function), while the other components serve only as aids for connection, fastening, guidance, etc. 3. Components – Under normal circumstances, all parts and components other than the frame are collectively referred to as components. Of course, the rack is also a component. Fittings: Parts that connect pipes to form a piping system. Based on the connection method, they can be divided into four categories: socket fittings, threaded fittings, flanged fittings, and welded fittings. It is often made from the same material as pipes. There are elbows, tees, crosses, and reducers, etc.

Question: Under what circumstances should forgings be used?； Under what circumstances are castings used: Q is confused. . .

Forgings are generally used in applications with high pressure, while castings are used in low and medium pressure environments. General-purpose forgings at 4.0 MPa and above.

Others have already spoken; I’ll talk about the processed parts. They can be divided into those still to be processed and those that have already been processed. The parts that are still to be processed are like forged pieces that have been taken to a lathe for further processing, while the latter represent the finished products that have already been processed