1.a Define and describe primary processes
A Primary Process is changing a raw material into a standard stock. This is a rather ambiguous definition as some processes can be a primary process or secondary process depending on the product being produced. For example pig iron from a blast furnace can be standard stock (for cast iron) or it can be sent to a BOS furnace for further processing into steel, which is the standard stock in this case.
Some basic examples of primary processes are:
Wood
Trees are cut down from native, regrowth or plantation forests. The trees are debarked and stripped of their limbs onsite by a special machine. This is then taken to a sawmill where they cut the wood to the correct thickness and length, known as timber. Later this can be treated, dried and shaped as a secondary process.
Steel
Iron ore is dug up from the mines and crushed and screened to the correct size fraction, where it is sent to the blast furnace. The blast furnaces uses iron ore, sinter (agglomeration of iron ore, coke and flux fines), and coke to smelt and reduce the iron oxides into liquid iron. This is done by blasting hot in the bottom of the furnace, combusting the coke and producing reducing gasses which helps reduce the iron oxides into iron. Molten iron is then cast into ladles and sent to the BOS (Basic Oxygen Steelmaking) furnace. A lance is injected into the vessel with oxygen at supersonic speeds to remove the carbon from the molten iron into form molten steel. Alloys are then added and cast into the steel stock (slabs, ingots, bar, ect...)
Aluminium
Bauxite is dug out of the ground and refined into alumina. Alumina is produced commercially by the Bayer Process. This is done by 4 main s...
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...the bike by a machine or hand. The chain links are coated in nickel and chrome for corrosion protection, and lubricants to prevent wear from the sprockets.
Overall
Most components of bikes are either made out of steel or aluminium. Aluminium is commonly being used to replace components of steel bicycles as it is much lighter and retains nearly as much strength. Aluminium is more corrosive resistant and has a more aesthetically pleasing surface finish compared to steel. This is extremely important to bicycle design as a product that corrodes less and is lighter appeals to cyclists.
Painting is another important part of bicycle construction. Most parts are painted for corrosion resistance and for aesthetic qualities. Whereas some parts, mainly the moving parts (sprockets and chain) are not painted so paint does not flake off and erode the gear systems.
The purpose for this lab was to use aluminum from a soda can to form a chemical compound known as hydrated potassium aluminum sulfate. In the lab aluminum waste were dissolved in KOH or potassium sulfide to form a complex alum. The solution was then filtered through gravity filtration to remove any solid material. 25 mLs of sulfuric acid was then added while gently boiling the solution resulting in crystals forming after cooling in an ice bath. The product was then collected and filter through vacuum filtration. Lastly, crystals were collected and weighed on a scale.
"Selective cutting" is the practice by which trees are cut down according to certain ascertainable features. If a tree were so old and large that it inhibited the growth of other trees, then it would be a prime target for timber. Trees can hinder the growth of other trees by means of overbearing roots or overgrowth of branches that would not permit sunlight to reach smaller and less developed trees.(p17-18) "Clear cutting", however, takes an entirely different approach. Rather than a few trees that are undoubtedly ready to be timbered, all the trees in the area would simply be cut down. There would be no selection process involved and nothing would be left of the surrounding trees.(p18-19) The last process is called "sustained yeild". Murphy said, "…others might cut themselves out of existence, but his company would never lack timber ready to fell. It’s annual cut would always be limited and never exceed its timberland’s newgrowth."(p18)
"Production of Refractory Metal Powders," in Powder Metal Technologies and Applications, vol. 7, 1998, pp. 188-201.
Logging was the process of cutting down numerous amounts of trees to use wood in a capitalist way or to clear land for agricultural purposes. Two main techniques were used by the settlers to clear away these large forests. One technique was called girdling. Girdling is the process of cutting a strip of bark off of the circumference of the tree which eventually killed it. Another technique used for deforestation is the "cut and burn" method. This method was the process of cutting down many of the trees and burning the rest of the brush and plants to clear land.
These bikes are made up of a wide range of materials such as steel, which is inexpensive, strong, and is easy to work with. Aluminum is lightweight, inexpensive and non corrosive. Titanium is light, strong non corrosive and shock absorbing. Carbon fiber which is the lightest, strongest with unlimited frame design possibilities and excellent shock absorption. The distribution for the compa...
the iron ore to iron. In the other cases of metals the most common way
A bauxite is a mixture consisting of hydrated aluminum oxide minerals and mineral impurities which are formed by weathered aluminum bearing rocks. In 1891 bauxite was mined in Alabama from the Rock Run. However, mining came to a sudden stop because metallurgical grade bauxite became very hard to obtain. Production started back up in 1927 and has been running on a maintained basis. Due to irregular distributions of bauxite deposits, exploratory test drilling must be conducted before any mining. Alabama bauxite is used in the making of high temperature products, abrasives, and chemicals. (Tew, 6)
...cial direct smelting process with plenty of advantages such as lower capital intensity,reduced enviromental inpact and operational fexibility, Pilbara operations contaings top notch network of 15 iron mines that are intergrated with 1500 kilometre rail network can respond to rapidly to changes in demands, new technologies to bring in higher efficiency, lower production costs and improved health, environmental performance and safety.
gears, which has caused no problems. The reason why I have this odd wheel setup is because I
Composites do most of the things metals can do in a bike frame. Although, often the way you go about building with composites is different than if using metals. With composite construction a mold has to be built to form the required shape and then the fibers and resin are held in the mold to harden. With metal tubing construction, off the shelf tubes a...
Some of the key parts of any bicycle are the frame, forks and wheels. The most common type of bicycle frame is known as the double diamond. It is called this because if you look at the frame, it is diamond shaped with 2 smaller triangles forming the front and rear. This designed has endured because it is easy to build, strong and efficient. The tubing that a frame is made with is usually round but can be many different shapes even on the same bike. The reason for this shaping is to increase the rigidity or improve the ride quality. For instance, the sloping tube that goes from the front of the bike to the pedal junction of the frame is sometimes ovalized along the horizontal axis at the pedal junction to make the frame flex less side to side. Frames have been made from many materials including wood, steel, aluminum, titanium and carbon fiber just to name a few. Each of the materials have a strength to weight ratio, tensile strength and cost of production that must be taken into account before deciding which will work best. For example, when a frame made of beryllium was introduced, the strength to weight ratio was very high. The weight was extremely low but the cost wa...
Smelting starts with simple raw (hematite and magnetite) ore to make iron by removing impurities. It includes the endothermic reaction of adding carbon to remove oxygen from iron and as the charcoal, limestone, and iron melted in the furnace, cold blasts of air would be forced into the molten mixture to make the fire hotter so that the slag could be separated from the pig iron. Limestone, referred to as flux, eased the difficulty of the separation between impurities and usable iron. Slag is lighter that pig iron so it floated in the furnace and was evacuated through a hole higher up the furnace while the iron was ushered into a flat basin at the bottom of the furnace. In the more industrialized cities, the blast furnace would almost constantly have charcoal and iron ore burning to continue the momentum of smelting because the furnaces required a great deal of energy and resources to start the process of heating the ore to the required degree to melt and separate, which was often around 1500 degrees
Wood has been one of the most important building materials from early times, both for building and for the manufacturing of tools, weapons, and furniture (Youngs, 2011). Wood is a hard, tough substance which forms the trunks of trees and that has been used for thousands of years as a fuel and as a material of construction (Abdul-wahab, 2008; Youngs, 2011). Processing of wood according to the Environment Protection Authority (EPA, 2007) is the conduct of works where timber is sawn, cut, chipped, compressed, milled or machined with a total processing capacity not exceeding 4000 cubic metres per year (other than works at a builders supply yard or home improvement centre). Some of these products include; Sawn wood, wood elements, doors and windows, kitchen furniture, bedroom furniture, armchair, other wood products (Stark, Cai, & Carll, 2010).
...it is one of main metals used in the manufacturing of products in high demand by modern society. The process of extracting pure aluminium from mined bauxite is a complicated step-by-step procedure researched and produced by chemists. Aside from aluminium itself, bauxite mines have its disadvantages as well including environmental issues, health related issues, and aesthetical impairments. An example of an environmental issue would be air pollution. Diseases such as silicosis (a respiratory disease) can be induced from the inhalation of mining dust. Bauxite mines are generally found around the equator in tropical regions. To create space for these mines, lush areas of nature would have to be removed. This causes aesthetical impairment for visual enjoyers. As aluminium's demand in society rises, so will its advantages, disadvantages, and scientific research.