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Galvanized Steel
Galvanization ( also spelled galvanisation) is the process of applying a protective zinc coating to steel or iron, to prevent rusting. The most common method is hot-dip galvanizing, in which the parts are coated by submerging them in a bath of hot, molten zinc. Protective action The zinc coating, when intact, prevents corrosive substances from reaching the underlying iron. It's main function is to act as a sacrificial anode to prevent the iron from rusting by cathodic protection. Zinc is more reactive than iron, so the zinc coating preferentially oxidizes to zinc carbonate, preventing the iron from corroding, even if there are gaps in the zinc coating. Additional electroplating such as a chromate conversion coating may be applied to provide further surface passivation to the substrate material. History and etymology The process is named after the Italian physician, physicist, biologist and philosopher Luigi Galvani (9 September 1737 – 4 December 1798). The earliest know ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hot-dip Galvanizing
Hot-dip galvanization is a form of galvanization. It is the process of coating iron and steel with zinc, which alloys with the surface of the base metal when immersing the metal in a bath of molten zinc at a temperature of around . When exposed to the atmosphere, the pure zinc (Zn) reacts with oxygen (Oxygen, O2) to form zinc oxide (ZnO), which further reacts with carbon dioxide (CO2, CO2) to form zinc carbonate (Smithsonite, ZnCO3), a usually dull grey, fairly strong material that protects the steel underneath from further corrosion in many circumstances. Galvanized steel is widely used in applications where corrosion resistance is needed without the cost of stainless steel, and is considered superior in terms of cost and life-cycle. It can be identified by the crystallization patterning on the surface (often called a "spangle"). Galvanized steel can be welded; however, one must exercise caution around the resulting toxic zinc fumes. Galvanized fumes are released when the ga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plumbing
Plumbing is any system that conveys fluids for a wide range of applications. Plumbing uses piping, pipes, valves, piping and plumbing fitting, plumbing fixtures, Storage tank, tanks, and other apparatuses to convey fluids. HVAC, Heating and cooling (HVAC), Sewerage, waste removal, and Drinking water, potable water delivery are among the most common uses for plumbing, but it is not limited to these applications. The word derives from the Latin for lead, ''plumbum'', as the first effective pipes used in the Sanitation in ancient Rome, Roman era were lead pipes. In the developed world, plumbing infrastructure is critical to public health and sanitation. Boilermakers and pipefitters are not plumbers although they work with piping as part of their trade and their work can include some plumbing. History Plumbing originated during ancient civilizations, as they developed public baths and needed to provide drinking water, potable water and sewerage, wastewater removal for large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tap Water
Tap water (also known as running water, piped water or municipal water) is water supplied through a Tap (valve), tap, a water dispenser valve. In many countries, tap water usually has the quality of drinking water. Tap water is commonly used for drinking, cooking, and washing. Indoor tap water is distributed through indoor plumbing, which has been around since History of plumbing, antiquity but was available to very few people until the second half of the 19th century when it began to spread in popularity in what are now developed country, developed countries. Tap water became common in many regions during the 20th century, and is now lacking mainly among people in poverty, especially in developing country, developing countries. Governmental agencies commonly regulate Drinking water quality standards, tap water quality. Calling a water supply "tap water" distinguishes it from the other main types of fresh water which may be available; these include water from Rainwater harvesti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pipe (fluid Conveyance)
Pipe(s), PIPE(S) or piping may refer to: Objects * Pipe (fluid conveyance), a hollow cylinder following certain dimension rules ** Piping, the use of pipes in industry * Smoking pipe ** Tobacco pipe * Half-pipe and quarter pipe, semi-circular ramps for performing skateboarding/snowboarding tricks * Piping (sewing), tubular ornamental fabric sewn around the edge of a garment * ''For the musical instruments'', see #Music, below Music * Pipe (instrument), a traditional perforated wind instrument * Bagpipe, a class of musical instrument, aerophones using enclosed reeds ** Pipes and drums or pipe bands, composed of musicians who play the Scottish and Irish bagpipes * Organ pipe, one of the tuned resonators that produces the main sound of a pipe organ * Pan pipes, see Pan flute, an ancient musical instrument based on the principle of the stopped pipe * Piped music, or elevator music, a type of background music * "Pipe", by Christie Front Drive from ''Christie Front Drive (EP), Christ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cast Iron Pipe
Cast iron pipe is Pipe (fluid conveyance), pipe made predominantly from gray cast iron. It was historically used as a pressure pipe for transmission of water, gas and sewage, and as a water drainage pipe during the 17th, 18th, 19th and 20th centuries. In many modern applications, cast iron pipe has been replaced by ductile iron pipe, but this newer product is still often loosely referred to by the older historical name. History The oldest cast iron water pipes date from the 17th century and were installed to distribute water throughout the gardens of the Chateau de Versailles. These amount to some 35 km of pipe, typically 1 m lengths with flanged joints. The extreme age of these pipes make them of considerable historical value. Despite extensive refurbishment in 2008 by Saint-Gobain PAM, 80% remain original. Cast iron proved to be a beneficial material for the manufacture of water pipes and was used as a replacement for the original elm pipelines utilized earlier. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfur Dioxide
Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is released naturally by volcanic activity and is produced as a by-product of metals refining and the burning of Sour gas, sulfur-Sour crude oil, bearing fossil fuels. Sulfur dioxide is somewhat toxic to humans, although only when inhaled in relatively large quantities for a period of several minutes or more. It was known to medieval alchemy, alchemists as "volatile spirit of sulfur". Structure and bonding SO2 is a bent molecule with ''C''2v Point groups in three dimensions, symmetry point group. A valence bond theory approach considering just ''s'' and ''p'' orbitals would describe the bonding in terms of resonance (chemistry), resonance between two resonance structures. The sulfur–oxygen bond has a bond order of 1.5. There is support f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paint
Paint is a material or mixture that, when applied to a solid material and allowed to dry, adds a film-like layer. As art, this is used to create an image or images known as a painting. Paint can be made in many colors and types. Most paints are either oil-based or water-based, and each has distinct characteristics. Primitive forms of paint were used tens of thousands of years ago in cave paintings. Clean-up solvents are also different for water-based paint than oil-based paint. Water-based paints and oil-based paints will cure differently based on the outside ambient temperature of the object being painted (such as a house). History Paint was used in some of the earliest known human artworks. Some cave paintings drawn with red or yellow ochre, hematite, manganese oxide, and charcoal may have been made by early ''Homo sapiens'' as long as 40,000 years ago. Paint may be even older. In 2003 and 2004, South African archeologists reported finds in Blombos Cave of a 100,000-y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rust 1
Rust is an iron oxide, a usually reddish-brown oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides (Fe2O3·nH2O) and iron(III) oxide-hydroxide (FeO(OH), Fe(OH)3), and is typically associated with the corrosion of refined iron. Given sufficient time, any iron mass, in the presence of water and oxygen, could eventually convert entirely to rust. Surface rust is commonly flaky and friable, and provides no passivational protection to the underlying iron unlike other metals such as aluminum, copper, and tin which form stable oxide layers. ''Rusting'' is the common term for corrosion of elemental iron and its alloys such as steel. Many other metals undergo similar corrosion, but the resulting oxides are not commonly called "rust". Several forms of rust are distinguishable both visually and by spectroscopy, and form under different circumstances. Other forms of rust include the result of rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sherardizing
Sherardising or Zinc thermal diffusion is a process of galvanization of ferrous metal surfaces, also called vapour galvanising and dry galvanizing. The process is named after British metallurgist Sherard Osborn Cowper-Coles (son of naval inventor Cowper Phipps Coles) who invented and patented the method c. 1900. This process involves heating the steel parts up to 500 °C in a closed rotating drum that contains metallic zinc dust and possibly an inert filler, such as sand.H. G. Arlt, "Finishes on the Metal Parts of Telephone Apparatus", ''Bell Laboratories Record'', Volume 9(4), 175 (December 1932) At temperatures above 300 °C, zinc evaporates and diffuses into the steel substrate forming diffusion bonded Zn-Fe-phases. Sherardising is ideal for small parts and parts that require coating of inner surfaces, such as batches of small items. Part size is limited by drum size. It is reported that pipes up to 6 m in length for the oil industry are sherardised. If the metal surface is fre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Embrittlement
Hydrogen embrittlement (HE), also known as hydrogen-assisted cracking or hydrogen-induced cracking (HIC), is a reduction in the ductility of a metal due to absorbed hydrogen. Hydrogen atoms are small and can Permeation, permeate solid metals. Once absorbed, hydrogen lowers the Stress (mechanics), stress required for cracks in the metal to initiate and propagate, resulting in embrittlement. Hydrogen embrittlement occurs in steels, as well as in iron, nickel, titanium, cobalt, and their alloys. Copper, aluminium, and stainless steels are less susceptible to hydrogen embrittlement. The essential facts about the nature of hydrogen embrittlement have been known since the 19th century. Hydrogen embrittlement is maximised at around room temperature in steels, and most metals are relatively immune to hydrogen embrittlement at temperatures above 150 °C. Hydrogen embrittlement requires the presence of both atomic ("diffusible") hydrogen and a Stress (mechanics), mechanical stress to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrogalvanization
Electrogalvanizing is a process in which a layer of zinc is bonded to steel to protect against corrosion, enhance adhesion, or give an aesthetic appeal. The process involves electroplating, running a current of electricity through a saline-/zinc-based electrolytic solution with a zinc anode and steel cathode. Such zinc electroplating or zinc alloy electroplating maintains a dominant position among other electroplating process options, based upon electroplated tonnage per annum. According to the International Zinc Association, more than 5 million tons are used yearly for both hot-dip galvanization and electroplating. The plating of zinc was developed at the beginning of the 20th century. At that time, the electrolytic solution was cyanide-based. A significant innovation occurred in the 1960s with the introduction of the first acid chloride-based electrolyte. The 1980s saw a return to alkaline electrolytes, only this time, without the use of cyanide. The most commonly used electrogalva ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
