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Spoke Nipple
A spoke nipple holds a bicycle wheel's rim to each spoke. The spoke nipple is a headed cylinder with threading on the inside through part of its length (there is an unthreaded lead-in nearest the "flats"). Traditionally, the nipples fit in holes in the rim, so that the head of the nipple is on the outermost part of the rim, while the other end of the nipple points inwards towards the hub. Many different types of nipples are now available, including internal nipples that sit entirely within the rim and can only be adjusted by removing the tire, as well as externally threaded nipples that thread into the rim (such as those used by Mavic Ksyriums). The threading grasps the spoke, so turning it increases or decreases tension in the spoke and influences the position of the hub relative to the rim. Thread pitch can vary with thread size, but is 0.454mm for common spoke thicknesses, which use thread types Fg 2, Fg 2.3 or Fg 2.6. Since spoke threading and nipple threading must match, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicycle Spoke Nipples
A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist. Bicycles were introduced in the 19th century in Europe. By the early 21st century, more than 1 billion were in existence. These numbers far exceed the number of cars, both in total and ranked by the number of individual models produced. They are the principal means of transportation in many regions. They also provide a popular form of recreation, and have been adapted for use as children's toys, general fitness, military and police applications, courier services, bicycle racing, and bicycle stunts. The basic shape and configuration of a typical upright or "safety bicycle", has changed little since the first chain-driven model was developed around 1885. However, many details have been improved, especially since the advent of modern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicycle Wheel
A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels. Bicycle wheels are typically designed to fit into the bicycle frame, frame and bicycle fork, fork via Dropout (bicycle part), dropouts, and hold bicycle tires. Invention The first wheel to use the tension in wire wheel, metal spokes was invented by George Cayley, Sir George Cayley to achieve lightness in his 1853 glider. Construction The first bicycle wheels followed the traditions of carriage building: a wooden hub, a fixed steel axle (the bearings were located in the fork ends), wooden spokes and a shrink fitted iron tire. A typical modern wheel has a metal hub, wire tension spokes and a metal or carbon fiber rim which holds a pneumatic rubber tire. Hub A hub is the center part of a bicycle wheel. It consists of an axle, bearing (mechanical), bearings and a hub shell. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spoke
A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface. The term originally referred to portions of a log that had been riven (split lengthwise) into four or six sections. The radial members of a wagon wheel were made by carving a spoke (from a log) into their finished shape. A spokeshave is a tool originally developed for this purpose. Eventually, the term spoke was more commonly applied to the finished product of the wheelwright's work, than to the materials they used. History The spoked wheel was invented to allow the construction of lighter and swifter vehicles. Earliest physical evidence for spoked wheels were found in Sintashta culture, dating to 2000 BC. Soon after this, horse cultures of the Caucasus region used horse-drawn spoked-wheel war chariots for the greater part of three centuries. They moved deep into the Greek peninsula where they joined with the exis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Screw Thread
A screw thread, often shortened to thread, is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a ''straight'' thread and the latter called a ''tapered'' thread. A screw thread is the essential feature of the screw as a simple machine and also as a threaded fastener. The mechanical advantage of a screw thread depends on its ''lead'', which is the linear distance the screw travels in one revolution. In most applications, the lead of a screw thread is chosen so that friction is sufficient to prevent linear motion being converted to rotary, that is so the screw does not slip even when linear force is applied, as long as no external rotational force is present. This characteristic is essential to the vast majority of its uses. The tightening of a fastener's screw thread is comparable to driving a wedge into a gap until it sticks fast thro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tension (mechanics)
In physics, tension is described as the pulling force transmitted axially by the means of a string, a rope, chain, or similar object, or by each end of a rod, truss member, or similar three-dimensional object; tension might also be described as the action-reaction pair of forces acting at each end of said elements. Tension could be the opposite of compression. At the atomic level, when atoms or molecules are pulled apart from each other and gain potential energy with a restoring force still existing, the restoring force might create what is also called tension. Each end of a string or rod under such tension could pull on the object it is attached to, in order to restore the string/rod to its relaxed length. Tension (as a transmitted force, as an action-reaction pair of forces, or as a restoring force) is measured in newtons in the International System of Units (or pounds-force in Imperial units). The ends of a string or other object transmitting tension will exert forces on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brass
Brass is an alloy of copper (Cu) and zinc (Zn), in proportions which can be varied to achieve different mechanical, electrical, and chemical properties. It is a substitutional alloy: atoms of the two constituents may replace each other within the same crystal structure. Brass is similar to bronze, another copper alloy, that uses tin instead of zinc. Both bronze and brass may include small proportions of a range of other elements including arsenic (As), lead (Pb), phosphorus (P), aluminium (Al), manganese (Mn), and silicon (Si). Historically, the distinction between the two alloys has been less consistent and clear, and modern practice in museums and archaeology increasingly avoids both terms for historical objects in favor of the more general "copper alloy". Brass has long been a popular material for decoration due to its bright, gold-like appearance; being used for drawer pulls and doorknobs. It has also been widely used to make utensils because of its low melting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel Electroplating
Nickel electroplating is a technique of electroplating a thin layer of nickel onto a metal object. The nickel layer can be decorative, provide corrosion resistance, wear resistance, or used to build up worn or undersized parts for salvage purposes. Overview Nickel electroplating is a process of depositing nickel onto a metal part. Parts to be plated must be clean and free of dirt, corrosion, and defects before plating can begin. To clean and protect the part during the plating process, a combination of heat treating, cleaning, masking, pickling, and etching may be used. Once the piece has been prepared it is immersed into an electrolyte solution and is used as the cathode. The nickel anode is dissolved into the electrolyte to form nickel ions (Ni2+). Just like in other electrodeposition processes, the ions travel through the solution and deposit on the cathode. The anode efficiency for nickel dissolution is close to 100%, unless due to problems with the process anode becomes pas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminum
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It has a great affinity towards oxygen, and forms a protective layer of oxide on the surface when exposed to air. Aluminium visually resembles silver, both in its color and in its great ability to reflect light. It is soft, non-magnetic and ductile. It has one stable isotope, 27Al; this isotope is very common, making aluminium the twelfth most common element in the Universe. The radioactivity of 26Al is used in radiodating. Chemically, aluminium is a post-transition metal in the boron group; as is common for the group, aluminium forms compounds primarily in the +3 oxidation state. The aluminium cation Al3+ is small and highly charged; as such, it is polarizing, and bonds aluminium forms tend towards covalency. The strong affinity towards ox ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galling
Galling is a form of wear caused by adhesion between sliding surfaces. When a material galls, some of it is pulled with the contacting surface, especially if there is a large amount of force compressing the surfaces together. Galling is caused by a combination of friction and adhesion between the surfaces, followed by slipping and tearing of crystal structure beneath the surface. This will generally leave some material stuck or even friction welded to the adjacent surface, whereas the galled material may appear gouged with balled-up or torn lumps of material stuck to its surface. Galling is most commonly found in metal surfaces that are in sliding contact with each other. It is especially common where there is inadequate lubrication between the surfaces. However, certain metals will generally be more prone to galling, due to the atomic structure of their crystals. For example, aluminium is a metal that will gall very easily, whereas annealed (softened) steel is slightly mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanium
Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in sea water, aqua regia, and chlorine. Titanium was discovered in Cornwall, Great Britain, by William Gregor in 1791 and was named by Martin Heinrich Klaproth after the Titans of Greek mythology. The element occurs within a number of minerals, principally rutile and ilmenite, which are widely distributed in the Earth's crust and lithosphere; it is found in almost all living things, as well as bodies of water, rocks, and soils. The metal is extracted from its principal mineral ores by the Kroll and Hunter processes. The most common compound, titanium dioxide, is a popular photocatalyst and is used in the manufacture of white pigments. Other compounds include titanium tetrachloride (TiCl4), a component of smoke screens and catalysts; and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corrosion Resistance
Corrosion is a natural process that converts a refined metal into a more chemically stable oxide. It is the gradual deterioration of materials (usually a metal) by chemical or electrochemical reaction with their environment. Corrosion engineering is the field dedicated to controlling and preventing corrosion. In the most common use of the word, this means electrochemical oxidation of metal in reaction with an oxidant such as oxygen, hydrogen or hydroxide. Rusting, the formation of iron oxides, is a well-known example of electrochemical corrosion. This type of damage typically produces oxide(s) or salt(s) of the original metal and results in a distinctive orange colouration. Corrosion can also occur in materials other than metals, such as ceramics or polymers, although in this context, the term "degradation" is more common. Corrosion degrades the useful properties of materials and structures including strength, appearance and permeability to liquids and gases. Many structural ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spoke Wrench
A spoke wrench or spoke key is a small wrench or tool used to adjust the tension in the spokes of a tension-spoked wheel. A spoke wrench is sometimes called a nipple wrench, as it is the spoke nipple – not the spoke – that is turned in the process of changing the tension of a spoke. Overview Spoke nipples are typically T-shaped in cross section, with an internal thread running part of the way through the hole that runs along the spoke nipple's principal axis. A spoke nipple rests in a hole drilled radially through the wheel's rim, and the nipple is threaded onto the external thread of a spoke. The spoke itself is fixed, at its other end, through a hole in the hub. The spoke and nipple are functionally equivalent to a bolt and a nut. However, unlike a typical nut-and-bolt pair, a spoke and nipple do not join two parts (the rim and the hub) so much as bridge them, under tension. The area of the nipple around which the spoke wrench, or key, is fitted is generally square in cross-s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
