ENGINEERING DRAWING.

WHAT IS ENGINEERING DRAWING.
--engineering drawing is entirely a grapic .  language drawing equipment and instrument are needed to record information on drawing paper or any other suitable surface. drawing paper or any other suitable surface . drawing composed of straight line, curve, circle  and arcs is prepared with certain instrument .
the quality of a drawing depends to a large extent on the quality, adjustment and care of the instrument are used.
the correct selection and use of pencil and drawing instrument is important.
the various instrument of other drafting equipment are described

*LIST OF EQUIPMENT
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*THE FOLLOWING LIST OF EQUIPMENT IS A PRACTICAL SELECTION AND CONSTITUTES A SET OR KIT OF INSTRUMENT-
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1. Drawing Board
2. T-Square or Mini-Drafter
3.Instrument Box Containing
  .large size compass including  pen attachment and lengthening bar
  .large size divider
  .two rulling pens
  .box of leads
4. triangles or set squares , -45, 30,-60
5.engineering scale
6.protractor
7.drawing pencils, HB,H,2H,3H
8.Drawing paper
9.Pencil Sharpener
10.Sand Paper Pad
11.Pencil Eraser
12.Clamps Cellotape  or Drafting Tape
13.French or irregular curve
14. clinigraph or adjustable set square
15.dusting   cloth
16.drawing ink:( black , water proof)
17. tracing paper , cloth  or myler
18.erasing shield
19.artgum  or other cleaning eraser.

A MANUFACTURING PROCESS OF IRON AND STEEL

1. Manufacturing processes
2. Manufacturing processes are the steps through which raw materials are transformed into a final product. The manufacturing process begins with the creation of the materials from which the design is made. These materials are then modified through manufact The manufacturing process begins with the creation of the materials from which the design is made. These materials are then modified through manufacturing processes to become the required part. Manufacturing processes can include treating (such as heat treating or coating), machining, or reshaping the material. The manufacturing process also includes tests and checks for quality assurance during or after the manufacturing, and planning the production process prior to manufacturing. 

A MANUFACTURING PROCESS OF IRON AND STEEL

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iron and steel using the blast furnace and basic oxygen furnace (denoted BF and BOF hereinafter, respectively), which is presently the most commonly used method (51% of world steel production). After the BF-BOF process, molten steel is controlled to a target composition and temperature and is then cast by continuous casting machine to produce slabs, blooms, and billets. These castings are rolled to the required dimensions by the rolling mill to produce steel products. The smelting and refining process for iron and steel in the BF-BOF process involves the carbon reduction of iron ore (Fe2O3) in the BF to make molten iron, and decarburization of molten iron in the BOF to make molten steel. Major reducing agent in the BF is the carbon monoxide gas(CO) generated by the oxidation of the carbon(C) in coke. Consequently, carburization takes place at the same time as reduction, producing hot metal(molten iron) containing about 4% carbon. The hot metal is decarburized to the required carbon content in the BOF. The main reaction in this process is the oxidization of the carbon in the hot metal by both pure oxygen gas (O2) and iron oxide (Fe2O3). The residual oxygen, after contributing to this decarburization reaction, remains in the molten steel. This oxygen is fixed and removed by deoxidation reagents such as silicon and aluminum as SiO2 and Al2O3 or is removed as carbon monoxide gas in the subsequent vacuum degassing process. In addition to the BF-BOF process, there is another process which utilizes mainly scrap as an iron source, with some direct reduced iron whenever necessary. The direct reduced iron is produced by reducing iron ore with reformed natural gas, whose principal components are hydrogen, carbon monoxide, and methane. The scrap, along with direct reduced iron, is then melted in an electric arc furnace (denoted EAF hereinafter) to produce molten steel which is subsequently processed by the continuous casting machine, as mentioned above. The molten steel from the BOF and EAF is then deoxidized and alloying elements are added in the prescribed amounts. The molten steel is then held at the target temperature and continuously cast, and the castings obtained are cut to the prescribed length. After heating to the rolling temperature in a reheating furnace, these castings are hot-worked to the required products. Steel shapes, bars, and wire rods are worked on section and bar mills and wire-rod mills equipped with caliber rolls, plates are worked on reversing mills, and hot-rolled steel sheets are worked on hot strip mills. After pickling to remove scale from the surface, the hot-rolled steel sheets are worked to cold-rolled steel sheets on reversing mills or tandem rolling mills, and the cold-rolled steel sheets are tinned or galvanized as required to produce various surface-treated steel sheet products. Steel pipe is produced by forming and welding steel sheets or plates, or by piercing a billet and rolling to the final dimensions without a seam.