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Engineering Marathon (2 Viewers)
- Thread starter Bdogz
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ShowStopper
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Process Annelaing is suitable for softening cold worked low carbon steels and recognises that thers alloys are made mainly from ferrite. As ferrite recystalises at around 500 degrees Celsius, annealing between 500-600 deg. will produce total recrystillisation of the ferrite while leaving the small amount of pearlite in its stressed state.
Its much faster that full annealing and is the industrial process selected for softening this grade of steel.
Give an example of Radiographic examination.
Its much faster that full annealing and is the industrial process selected for softening this grade of steel.
Give an example of Radiographic examination.
the process of annealing is a process by which the metal is normalised. after it has been cold worked/rolled/forged/etc, it can be placed back into the furnice, heated upto a temprature near or above its austinisation temprature (recrystilisation temprature). it is then cooled out of the furnice to room temprature, where the crystaline structure that is formed as a result is equiaxied and strong.
another similar process to this is whats called quenching, where the metal is heated upto a temprature near or above its austinisation temprature, taken out of the furnice, and placed into either water or oil. the result of which creates a crystaline structure that has very small crystals and are not equal in size. the metal then has a much harder, stronger structure to it, allowing it to be more durable.
the 3rd similar process to this is whats called normalisation, which is very similar to the annealing process, but instead of being taken out of the furnace to be cooled at room temprature, it is left in the furnace, and is cooled at a much slower rate. this results in a crystaline structure that has much bigger crystals, and a much softer material. this metal is more maluable, and can be cold worked/rolled/work hardened to create a harder material.
that is what i have been taught by my engineering teacher, so if i have go that wrong, please tell me.
and i got no idea in the workd what radiographic examination is... could it be some kind of non-destructive testing? or has it got to do with telecomunication?
another similar process to this is whats called quenching, where the metal is heated upto a temprature near or above its austinisation temprature, taken out of the furnice, and placed into either water or oil. the result of which creates a crystaline structure that has very small crystals and are not equal in size. the metal then has a much harder, stronger structure to it, allowing it to be more durable.
the 3rd similar process to this is whats called normalisation, which is very similar to the annealing process, but instead of being taken out of the furnace to be cooled at room temprature, it is left in the furnace, and is cooled at a much slower rate. this results in a crystaline structure that has much bigger crystals, and a much softer material. this metal is more maluable, and can be cold worked/rolled/work hardened to create a harder material.
that is what i have been taught by my engineering teacher, so if i have go that wrong, please tell me.
and i got no idea in the workd what radiographic examination is... could it be some kind of non-destructive testing? or has it got to do with telecomunication?
X-ray testing: where a specimen is but in an x-ray machine to produce a photographic negative. The negative is developed into a positive. The photograph is examined for darker spots which indicate holes or bubbles.
Both engines contain a compressor, which intakes air and compresses it. This is then injected with fuel to make a fuel air miture. The mixture is ignited as it passes through the engine. The expanding gases provide thrust as they are exhausted from th engine, as well as a force to spin a turbine, which in turn spins a shaft. The same shaft houses the compressor on a turbojet engine. On a turboprop engine the shaft is connected to the compressor as well as a propeller to provide more thrust.
Q: Compare and contrast conrete to mortar.
Compare and contrast concrete and mortar:
Concrete is a composite material that consists of cement, sand and aggregate. The sand fills the gaps between the aggregate while the cement acts as the binder or matrix that holds everything together. Ratio is 4 parts aggregate, 2 parts sand, 1 part cement. Can be used for foundations, large floor slabs or other heavy duty applications.
Mortar is the material used between bricks in buildings. it consists of Portland cement, sand and lime in the ratio of 3:2:1. Note the disregard of aggregate compared to cement.
In both cases, water is used as the chemical reaction with the cement in a process called hydration.
Describe the process of modulation
Concrete is a composite material that consists of cement, sand and aggregate. The sand fills the gaps between the aggregate while the cement acts as the binder or matrix that holds everything together. Ratio is 4 parts aggregate, 2 parts sand, 1 part cement. Can be used for foundations, large floor slabs or other heavy duty applications.
Mortar is the material used between bricks in buildings. it consists of Portland cement, sand and lime in the ratio of 3:2:1. Note the disregard of aggregate compared to cement.
In both cases, water is used as the chemical reaction with the cement in a process called hydration.
Describe the process of modulation
Modulation:
Modulation is the process by whith a digital signal is broken down, and sent over a carrier signal to another receptor. An example of this can be seen in fiber-optic cables, where the digital signal is the frequency by which the light flashes, and the carrier signal is the light itself.
Signals sent down a fiber optic cable are in binary notation, ie. ones and zeros. The type of light that is used is very important for maintaining the quality signal, and most efficient bandwidth. Red light is used predominately, because it is of a low frequency, and is simple to produce in a fiber-optic situation.
The term 'Modem' is used in a Telecomunication scenario, and refers to the modulation and demodulation at either end of a cordless connection. This can be clearly seen in the wireless internet connections seen today, eg. WiFi.
Outline the role of an Engineer as a project manager.
Modulation is the process by whith a digital signal is broken down, and sent over a carrier signal to another receptor. An example of this can be seen in fiber-optic cables, where the digital signal is the frequency by which the light flashes, and the carrier signal is the light itself.
Signals sent down a fiber optic cable are in binary notation, ie. ones and zeros. The type of light that is used is very important for maintaining the quality signal, and most efficient bandwidth. Red light is used predominately, because it is of a low frequency, and is simple to produce in a fiber-optic situation.
The term 'Modem' is used in a Telecomunication scenario, and refers to the modulation and demodulation at either end of a cordless connection. This can be clearly seen in the wireless internet connections seen today, eg. WiFi.
Outline the role of an Engineer as a project manager.
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tashisthebest
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Outline the role of an Engineer as a project manager.[/quote]
An engineer as a project manager need to ensure the safety of the workers while in construction. He needs to keep the project under or on budget requirement while keeping the project structurally sound. He also need to keep the project within the time restrains. .... Stuff like tha.
Question : A car of mass 1.5 kg uses 115kw of power to accelrate up to 100km/hr in 10 seconds on a level surface
Calculate the power required by the brakes to stop the car in 4 seconds.
Answer is 144.68kN
An engineer as a project manager need to ensure the safety of the workers while in construction. He needs to keep the project under or on budget requirement while keeping the project structurally sound. He also need to keep the project within the time restrains. .... Stuff like tha.
Question : A car of mass 1.5 kg uses 115kw of power to accelrate up to 100km/hr in 10 seconds on a level surface
Calculate the power required by the brakes to stop the car in 4 seconds.
Answer is 144.68kN
mahdi
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lol a 1.5 kg car. Anyways...
the part about it taking 10 seconds to acelerate to that speed is irellevant.
Power = Work / Time
Work = change in PE + change in KE
since there is no change in PE
Work = 1/2 x 1.5 x 27.7squared (to convert km/hr to m/s multiply by 0.277)
so now Power = 578.703.. / 4
Power = 144.68.. Watts
the part about it taking 10 seconds to acelerate to that speed is irellevant.
Power = Work / Time
Work = change in PE + change in KE
since there is no change in PE
Work = 1/2 x 1.5 x 27.7squared (to convert km/hr to m/s multiply by 0.277)
so now Power = 578.703.. / 4
Power = 144.68.. Watts
Answer: yes
Question: In the following diagram; determine force and nature of force in member AB (HINT: determine reactions first)
I thought what you have described as normalising was full annealing?
This is how I understand it:
Process Annealing - heat to austenite (above recrystallisation temp of 723deg C), soak, cool in still air
Full Annealing - as process anneal, but cool in furnace
Normailising - heat to about 950deg C, cool in still air [edit: or maybe this is also furnace cooled as you described? any1 else to clarify??]
Quench Hardening - heat to 800 - 900 deg C, forms BCC? , quench in water or prefferably warm oil
Tempering - after hardening, heat to about 450 deg C (below recrystallisation temp), cool in air
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I got Rb = 90kN (up)
Ra = 61kN (80 degrees down to the left - hard to explain without diagram)
Dunno how to get force in AB tho. anyone help?
Edit: This is wrong! I misread 30kN force as 20kN
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tashisthebest
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Umm using your reactions at Rb 90 kn
i got force in member AB = 92kn
Arman is that the right answer? im not 2 confident with it tho
I don't think they are the correct reactions
[edit: I had this question uncompleted in my workbook from ages ago, and have done reactions twice, both times i got answers: Ra=100 (Rah=10kN and Rav= 100kN) Rb= 130kN
Last edited:
tashisthebest
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now that i do try 2 work it out insted of jut using thaa other guys answers. i did get Rb=130kn
now im getting my force in member AB = 132.90 Kn
Is tha right tho?
now im getting my force in member AB = 132.90 Kn
Is tha right tho?
idk, thats why i posted this question, but i got ABv = 120kN, did u get that?
i will post my working so far