Plaster molds, Other Engineering

Assignment Help:

           Plastic molds are made of plaster of Paris (gypsum) or calcium sulphate, talc and silica flour is added in the plaster of Paris to improve strength and to control the time required for the plaster to set. These ingredients are mixed with water and the resulting slurry is poured over the pattern.

           The plaster sets within 15 minutes usually. After the plaster sets, the pattern is removed and the mould is dried at 120°C -260°C to remove the moisture. The mould halves are assembled to form the mould cavity and are preheated to about 120°C. The molten metal is then poured into the mould.

           Patterns for plaster moulding are generally made of Aluminum, thermosetting plastics, brass or zinc alloys. Wood patterns are not appropriate for producing a large number of mould because they are repeatedly in contact with the water based plaster slurry.


Related Discussions:- Plaster molds

Case study, I need to get this case study done. Here is a link to the case...

I need to get this case study done. Here is a link to the case: Disregard">http://ss-edu.info/df/cases/Case%2094.pdf Disregard question 10.

Cash flow diagrams, Cash Flow Diagrams We will use a cash flow approac...

Cash Flow Diagrams We will use a cash flow approach to analyze the flow of money through out a planning horizon. A cash flow occurs when money actually change hands. We will u

Model independent option valuation , Derive the functional relationship bet...

Derive the functional relationship between the no-arbitrage values of the two vertical spreads, C (K1)-C (K2) and C (K2)-C (K3).

#title.electronic devices., Advantages and dis advantages of a diode in ser...

Advantages and dis advantages of a diode in series /shunt

Propeller balance, PROPELLER BALANCE There are two types of balance of ...

PROPELLER BALANCE There are two types of balance of importance when working with propellers: • Static Balance • Dynamic Balance Static balance is checked and corrected

Principles of fire alarm systems, Principles of Fire Alarm Systems: Fi...

Principles of Fire Alarm Systems: Fire alarm systems usually perform two primary functions.   Firstly, they provide a means for warning people throughout the building that the

Engine torque, ENGINE TORQUE It is the force of rotating action about t...

ENGINE TORQUE It is the force of rotating action about the crankshaft axis at any given instant of time. It is given by,

Skin-core debonding in sandwich structures, If the skins are peeled from th...

If the skins are peeled from the core, a sandwich structure loses its strength and stiffness. This can occur under - wave-slamming in fast ferries - rapid depressurisati

LIBS, Laser induced breakdown spectroscopy

Laser induced breakdown spectroscopy

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