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Showing posts from May, 2021

What is COUPLING in mechanical engineering - ITI ONLINE NOTE

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 Couplings  1- Shaft transportation problem are usually available up to 7 meters length more length causes as. 2- To have greater length, it is necessary to join two or more pieces of shafts by means of couplings . 3- Connect the ends of two shafts together.  4- Transmit power from one shaft to other shaft.  5- Reduce the vibrations.  6- Provide mechanical flexibility. 7- Permit misalignment of shafts. Requirements of couplings  1- It should be easy to connect or disconnect.  2- It should transmit full power of shaft. 3- It should hold the shafts in perfect alignment.  4- It should have no projecting parts.  Types of couplings  1- Rigid Couplings . 2- Flexible Couplings . Rigid couplings  1- It is used to connect two shafts which are perfectly aligned.  Types of rigid couplings  1- Sleeve or muff coupling .  2- Clamp or split muff couplings .  3- Flange coupling.   > Protected type . > Un protected type . > Marine type  Sleeve or muff coupling 1- Sleeve or muff coupling is th

Fluid power Pneumatics and Hydraulic System-FITTER ONLINE NOTE

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 Fluid power  1- The term " fluid power " relates to the employment of fluid media under controlled conditions to perform some useful work.  2- Fluid power in industry has been important in the development of automatic machinery and equipment for use in industrial plants. 3- There are two main branches of fluid power   i - Pneumatics , ii- Hydraulics i- Fluid power Pneumatics system 1- A  Fluid power   pneumatic system carries power by employing compressed gas, generally air, as a f luid for transmitting energy from an energy generating source to an energy using point to accomplish useful work.  2- Figure shows a simple circuit of a pneumatic system with basic components. 3- The functions of various components shown in figure are as follows:  4- The pneumatic actuator converts the fluid power into mechanical power to perform useful work.  5- The compressor is used to compress the fresh air drawn from the atmosphere.  6- The storage reservoir is used to store a given volu

Dial Test Indicator -FITTER ONLINE NOTE

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 What is Dial Test Indicator   1- In various manufacturing contexts an indicator is any of various instruments used to accurately measure small distances , and amplify them to make them more obvious .  2- Many indicators have a dial display , in which a needle points to graduations in a circular array around the dial . 3- Dial test indicators are instruments of high precision , used for comparing and determining the variation in the sizes of a component.  4- These instruments cannot give the direct reading of the sizes like micrometers and vernier calipers.  5- A dial test indicator magnifies small variations in sizes by means of a pointer on a graduated dial.  6- This direct reading of the deviations gives an accurate picture of the conditions of the parts being tested.  7- Indicators , of which there are several types , therefore are often called dial indicators .  Types of Dial Test Indicator  1- A dial test indicator , also known as a lever arm test indicator or finger indi

Lapping-Honing-FITTER ONLINE NOTE

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1. LAPPING:- i)- Lapping is a precision finishing operation carried out using fine abrasive materials. ii)- There are some jobs which need more accuracy and finishing even after machining and grinding. So for that the process adopted is called lapping.  iii)- This process lapping compound and lapping tool is used. iv)- Lapping is used on many jobs like piston pins, piston rings and gauge blocks etc. Advantages of Lapping:- (a)- Job gets super quality polish and finish. (b)- To raised the dots on the small points. (c)- Surface becomes so smooth and fine that both sides have vacuum. (d)- Less chances of rust. (e)- Job can be moved on high speed. (f)- Required fit can be obtained. 2. Lapping Process:- The lapping Process are Two types a)- Hand lapping of flat surfaces, b)- Wet and dry lapping. a)- Hand lapping of flat surfaces:-   i)-  Flat surfaces are hand- lapped using lapping plate. ii)- made out of close grained cast iron. iii)-  The surface of the plate should be in a true plane

How to Drilling and Boring Operation in Lathe Machine -Fitter Online Note

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 Drilling and Boring Operation in Lathe Introduction to drilling  1- Frequently, holes will need to be drilled using the lathe before other internal operations can be completed, such as boring , reaming, and tapping.  2- Although the lathe is not a drilling machine, time and effort are saved by using the lathe for drilling operations instead of changing the work to another machine. 3- Before drilling the end of a work piece on the lathe, the end to be drilled must be spotted and then center drilled so that the drill will start properly and be correctly aligned.  4- The headstock and tailstock spindles should be aligned for all drilling, reaming, and spindles should be aligned for drilling, reaming, and tapping operations in order to produce a true hole and avoid damage to the work and the lathe.  5- The purpose for which the hole is to be drilled will determine the proper size drill to use.  6- That is, the drill size must allow sufficient material for tapping, reaming, and boring.

DRILLING MACHINE DIFFERENT TYPES - ONLINE LEARNING

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 D ifferent types of  Drilling machines   What are types of Drill Machine? O There are principal types of drilling machines are given bellow,  1- The sensitive bench drilling machine .  2- The upright drilling machine .  3- The gang drilling machine .  4- The radial arm drilling machine (Radial drilling machine ). 1- Sensitive bench drilling machine  1- Sensitive drilling machine is a light duty drilling machine widely used in small workshops. 2- It is usually placed on workbenches, but can also be placed on the floor. 3- This machine enables the operator to sense or feel the cutting action and apply the required pressure while drilling, hence it is called sensitive drilling machine.  4- It is used to drill small size holes from diameter 1.5 to 15.5 mm. Parts of sensitive drilling machine  Base  1- Heavy casting made of cast iron.  2- Supports the column and other parts of the machine.  Vertical column  1- It is mounted on the base. 2- It carries a moving head.  3- It contains the

Maintenance of Machinery-Online Learning

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  Maintenance  How do you maintain a machine? 1- Total plant profitability is obviously affected both by on-stream factors and maintenance costs.  2- One cannot be separated from the other.  3- Any system, therefore, must account for how cheaply maintenance can be performed from an organizational setup, and also what must be done and how often.  4- The ability to update maintenance requirements and improved planning based on experience at a group of plants has a large bearing on overall maintenance costs.  5- Other than breakdown maintenance , all maintenance work is planned.  6- Some can be done while the plant is operating and the rest during shutdown.  7- The effectiveness of this planned or preventive maintenance (PM) program to reduce breakdowns and the organizational methods used to accomplish the planned major maintenance work will determine maintenance costs. 8- Preventive maintenance as discussed here covers all planned maintenance work, whether major or minor, regardles

Aluminum Characteristics of Non-ferrous Metals

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Aluminum   O Aluminum is one of the most abundant elements in the earth's crust and also the most important of Non-ferrous Metals . O Aluminum is a silvery white metal.  O It is a light metal with a density about a 1/3 of steel or brass.  O It is a good conductor of electricity.  o- On a conductivity to weight basis aluminum is a better conductor than copper.  O Aluminum is very ductile.  O Good corrosion resistance of aluminum is due to the thin oxide layer on its surface. o- Aluminum has great affinity for oxygen.  o- Any fresh metal in air rapidly oxidizes to give a thin layer of oxide on the metal surface.  o- This surface layer is not penetrated by oxygen and protects the metal from further attack. O Good conductor of heat, high thermal conductivity.  O Non magnetic. .  O Melting point of Aluminum= 650°C O Fusion range of Aluminum Alloys = 520°C to 650°C.  Characteristics of Aluminum   O Some of its main characteristics are,  o- Light - weight (One - th