CHEMICAL MACHINING In chemical machining, some chemicals are used to remove material from the required portions of the workpiece. This process is also called chemical milling. Chemical milling is done in the following steps. Cleaning The workpiece surface is carefully cleaned. Masking The portions of the workpiece which do not require machiningis covered with masking sheets. The sheet is cut
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Punching Punching is a piercing operation. It is the operation of producing a circular hole in a sheet metal using a punch and die. The material pushed out through the die is the scrap. The punch size will be exactly the same as the size of the hole to be pierced. The die opening is made slightly larger to get
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CLASSIFICATION OF COMPOUND STEAM ENGINE The compound steam engines are usually classified into two types: 1. Tandem compound steam engine 2. Cross compound steam engine TANDEM COMPOUND STEAM ENGINE In this type of engine, the two cylinders usually will have a common piston rod and fixed in tandem, working on the same crank shaft. These cylinders may be observed as
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Electro Chemical Grinding (ECG) Electro chemical grinding is also called electrolytic grinding. Metal is removed from the surface of the work piece by electro chemical action and also by abrasive action of a grinding wheel. 90% of metal is removed by electro chemical action and 10% of metal is removed by the abrasive action of the grinding wheel. The equipment
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Plasma arc machining When a free flowing gas is heated to a very high temperature it becomes partially ionized. This ionized gas is called as plasma. In this process metal is removed from the surface of the work piece with the help of high temperature plasma. Metal is also moved as a result of electron bombardment. This plasma arc machining
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Jet propulsion Jet propulsion is based on newton’s second law and third law of motion. Newton’s second law states that the rate of change of momentum in any direction is proportional to the force acting in that direction. Newton’s third law of motion states that for every action there is an equal and opposite reaction. A type of jet engine
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Honing process It is an abrasive process used for finishing previously machined surface. It is generally used for finishing drilled or bored holes. The tool used in this process is called as hone. Hone is a bonded abrasive stone made in the form of a stick. The honing tool works the same way as that of the expanding reamer. These
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Types of Broaching Machines Horizontal broaching machine In this machine, the broach moves in a horizontal direction. A pull type broach is used. The pull type broach removes metal when it is pulled through the work piece. Internal and external broaching are done in this machine. But horizontal broaching machine is mainly used for internal broaching. The machine has a
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Definition of Jig Jig is a device that firmly holds and locates work piece and also guides cutting tool during machining. Elements of Jig Jig body This is also called base. It supports work piece by locators and clamps. The base is fitted with four feet which rest on the machine table. Jig feet Jig has four feet at the
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Jet propulsion Jet propulsion is based on newton’s second law and third law of motion. Newton’s second law states that the rate of change of momentum in any direction is proportional to the force acting in that direction. Newton’s third law of motion states that for every action there is an equal and opposite reaction. The types of jet engines
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