Blow hole and pin hole porosity, Other Engineering

Assignment Help:

Difference between Blow hole and pin hole porosity

         Blow hole : They appear as cavities in a casting. When they are visible on the upper surface of the castings, they are cooled open blows. These blows are normally rounded and have smooth walls.

         Pin hole porosity : This defect occurs in the castings in the form of pin hole porosity or gas porosity. These porosities are caused by the gases absorbed by the molten metal. The gases commonly absorbed and hydrogen, oxygen and nitrogen, the later two forming oxides and nitrides respectively. It is mainly hydrogen which is responsible for the pin hole porosity.


Related Discussions:- Blow hole and pin hole porosity

Variable interest rate, What is Variable Interest Rate? Interest rates whic...

What is Variable Interest Rate? Interest rates which is offered by banks or financial institutions on loans or deposits which are liable to change according to circumstances. For e

machine molding, Machine molding is suitable for the faster and uniform qu...

Machine molding is suitable for the faster and uniform quality moulds, needed for mass production of castings. For preparing the moulds, various moulding machines are used. Majorit

Torque indication - aircraft engine, Torque indication: Turboprop and t...

Torque indication: Turboprop and turboshaft engines do not provide significant thrust through their jet pipes, so EPR would not be of any use in determining the thrust being pr

Inhibit gate, Inhibit Gate Occasionally it is required to 'hold' one in...

Inhibit Gate Occasionally it is required to 'hold' one input to an AND gate at a particular logic level in order to disable the entire gate. One method of representing this sy

Matlab, 2. Write a MATLAB program to perform discounted reward value iterat...

2. Write a MATLAB program to perform discounted reward value iteration. Show me the MATLAB code and also an output from your code for solving the problem provided in the data above

What is basic function of subroutine, Question: a) Write the detailed ...

Question: a) Write the detailed operation/description of the following mnemonics: (i) MOVX @DPTR, A (ii) MOVC A, @A + PC (iii) PUSH add b) What is a subroutine and

Keplers’s three laws of planetary motion, Expertsmind.com brings you uniqu...

Expertsmind.com brings you unique solution in electrical engineering -          Ancient people kept track of time and seasons as it affected agriculture. -          Some

Corporate, Need help with a timed exam

Need help with a timed exam

Financial Ratio, The following information was extracted from the accountin...

The following information was extracted from the accounting records of De Walt Company as at 28 February 2011 (the end of their financial year): Sales (50% on credit) 1 400 000 Cos

Diffraction of light, what do you mean by diffraction of light? what is the...

what do you mean by diffraction of light? what is the diffrence between interference and diffraction of light?distinuish between Fresnel''s and Fraunhofer''s diffraction.

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd