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Rim (wheel)
The rim is the "outer edge of a wheel, holding the tire". It makes up the outer circular design of the wheel on which the inside edge of the tire is mounted on vehicles such as automobiles. For example, on a bicycle wheel the rim is a large hoop attached to the outer ends of the spokes of the wheel that holds the tire and tube. In cross-section, the rim is deep in the center and shallow at the outer edges, thus forming a "U" shape that supports the bead of the tire casing. In the 1st millennium BC, an iron rim was introduced around the wooden wheels of chariots to improve longevity on rough surfaces. Characteristics ;Design: The first pneumatic tires for bicycles were simple tubes in shape secured to the wooden outer concave surfaced circumference of the wheel by glue and air pressure pressing them against it. The surface for receiving the tube was not very secure thus causing the tires to sometimes come off the rims. Bicycle manufacturer and inventor Thomas B. Jeffery deve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrome Plating
Chrome plating (less commonly chromium plating) is a technique of electroplating a thin layer of chromium onto a metal object. A chrome-plated item is called ''chrome''. The chromed layer can be decorative, provide corrosion resistance, ease of cleaning, or increase surface hardness. Sometimes, a less expensive imitator of chrome may be used for aesthetic purposes. Process Chrome plating a component typically includes these stages: * Degreasing to remove heavy soiling * Manual cleaning to remove all residual traces of dirt and surface impurities * Various pretreatments depending on the substrate * Placement into the chrome plating vat, where it is allowed to warm to solution temperature * Application of plating current for the required time to attain the desired thickness There are many variations to this process, depending on the type of substrate being plated. Different substrates need different etching solutions, such as hydrochloric, hydrofluoric, and sulfuric acids. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Train Wheel
A train wheel or rail wheel is a type of wheel specially designed for use on railway tracks. The wheel acts as a rolling component, typically press fitted onto an axle and mounted directly on a railway carriage or locomotive, or indirectly on a bogie (in the UK), also called a ''truck'' (in North America). The powered wheels under the locomotive are called driving wheels. Wheels are initially cast or forged and then heat-treated to have a specific hardness. New wheels are machined using a lathe to a standardized shape, called a profile, before being installed onto an axle. All wheel profiles are regularly checked to ensure proper interaction between the wheel and the rail. Incorrectly profiled wheels and worn wheels can increase rolling resistance, reduce energy efficiency and may even cause a derailment. The International Union of Railways has defined a standard wheel diameter of , although smaller sizes are used in some rapid transit railway systems and on ro-ro carriages. Whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cone (geometry)
A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex. A cone is formed by a set of line segments, half-lines, or lines connecting a common point, the apex, to all of the points on a base that is in a plane that does not contain the apex. Depending on the author, the base may be restricted to be a circle, any one-dimensional quadratic form in the plane, any closed one-dimensional figure, or any of the above plus all the enclosed points. If the enclosed points are included in the base, the cone is a solid object; otherwise it is a two-dimensional object in three-dimensional space. In the case of a solid object, the boundary formed by these lines or partial lines is called the ''lateral surface''; if the lateral surface is unbounded, it is a conical surface. In the case of line segments, the cone does not extend beyond the base, while in the case of half-lin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rail Transport
Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a prepared flat surface, rail vehicles ( rolling stock) are directionally guided by the tracks on which they run. Tracks usually consist of steel rails, installed on sleepers (ties) set in ballast, on which the rolling stock, usually fitted with metal wheels, moves. Other variations are also possible, such as "slab track", in which the rails are fastened to a concrete foundation resting on a prepared subsurface. Rolling stock in a rail transport system generally encounters lower frictional resistance than rubber-tyred road vehicles, so passenger and freight cars (carriages and wagons) can be coupled into longer trains. The operation is carried out by a railway company, providing transport between train stations or freight customer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wire Wheels
Wire wheels, wire-spoked wheels, tension-spoked wheels, or "suspension" wheels are wheels whose rims connect to their hubs by wire spokes. Although these wires are generally stiffer than a typical wire rope, they function mechanically the same as tensioned flexible wires, keeping the rim true while supporting applied loads. The term ''suspension wheel'' should not be confused with vehicle suspension. Wire wheels are used on most bicycles and are still used on many motorcycles. They were invented by aeronautical engineer George Cayley in 1808. Although Cayley first proposed wire wheels, he did not apply for a patent. The first patent for wire wheels was issued to Theodore Jones of London, England on October 11, 1826. Eugène Meyer of Paris, France was the first person to receive, in 1869, a patent for wire wheels on bicycles. Bicycle wheels were not strong enough for cars until the development of tangentially spoked wheels. They rapidly became well established in the bicyc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rim (craters)
The rim or edge of an impact crater is the part that extends above the height of the local surface, usually in a circular or elliptical pattern. In a more specific sense, the rim may refer to the circular or elliptical edge that represents the uppermost tip of this raised portion. If there is no raised portion, the rim simply refers to the inside edge of the curve where the flat surface meets the curve of the crater bottom. Simple craters Smaller, simple craters retain rim geometries similar to the features of many craters found on the Moon and the planet Mercury. Complex craters Large craters are those with a diameter greater than 2.3 km, and are distinguished by central uplifts within the impact zone. These larger (also called “complex”) craters can form rims up to several hundred meters in height. A process to consider when determining the exact height of a crater rim is that melt may have been pushed over the crest of the initial rim from the initial impact, ther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coffee Cup
A coffee cup is a container that coffee and espresso-based drinks are served in. Coffee cups are typically made of glazed ceramic, and have a single handle for portability while the beverage is hot. Ceramic construction allows a beverage to be drunk while hot, providing insulation to the beverage, and quickly washed with cold water without fear of breakage, compared to typical glassware. A coffee cup may also be a disposable cup in which hot beverages, including coffee, can be contained. Disposable coffee cups may be made out of paper or polystyrene foam. At coffee shops, paper cups are commonly used to give beverages to customers on the go, usually with a coffee cup sleeve to provide insulation against heat transferred through the container. A new alternative trend sees consumers purchasing reusable coffee cups instead of disposable cups as a more sustainable approach to coffee consumption becomes more popular. These can include bamboo cups, americano cups made from polypropyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forging
Forging is a manufacturing process involving the shaping of metal using localized compressive forces. The blows are delivered with a hammer (often a power hammer) or a die. Forging is often classified according to the temperature at which it is performed: cold forging (a type of cold working), warm forging, or hot forging (a type of hot working). 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.Degarmo, p. 389 Forging has been done by smiths for millennia; the traditional products were kitchenware, hardware, hand tools, edged weapons, cymbals, and jewellery. Since the Industrial Revolution, forged parts are widely used in mechanisms and machines wherever a component requires high strength; such forgings usually require further processing (such as machining) to achieve a finished part. Today, forging is a major worldwide industry. History Forging is one of the oldest known me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Casting
Casting is a manufacturing process in which a liquid material is usually poured into a mold, which contains a hollow cavity of the desired shape, and then allowed to solidify. The solidified part is also known as a ''casting'', which is ejected or broken out of the mold to complete the process. Casting materials are usually metals or various ''time setting'' materials that cure after mixing two or more components together; examples are epoxy, concrete, plaster and clay. Casting is most often used for making complex shapes that would be otherwise difficult or uneconomical to make by other methods. Heavy equipment like machine tool beds, ships' propellers, etc. can be cast easily in the required size, rather than fabricating by joining several small pieces. Casting is a 7,000-year-old process. The oldest surviving casting is a copper frog from 3200 BC. History Throughout history, metal casting has been used to make tools, weapons, and religious objects. Metal casting history and de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lug Nut
A lug nut or wheel nut is a fastener, specifically a nut, used to secure a wheel on a vehicle. Typically, lug nuts are found on automobiles, trucks (lorries), and other large vehicles using rubber tires. Design A lug nut is a nut fastener with one rounded or conical (tapered) end, used on steel and most aluminum wheels. A set of lug nuts is typically used to secure a wheel to threaded wheel studs and thereby to a vehicle's axles. Some designs (Audi, BMW, Mercedes-Benz, Saab, Volkswagen) use lug bolts or wheel bolts instead of nuts, which screw into a tapped (threaded) hole in the wheel's hub or brake drum or brake disc. The conical lug's taper is normally 60 degrees (although 45 degrees is common for wheels designed for racing applications), and is designed to help center the wheel accurately on the axle, and to reduce the tendency for the nut to loosen due to fretting induced precession, as the car is driven. One popular alternative to the conical lug seating design is th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
