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

Installation of propeller, INSTALLATION OF PROPELLER The method of inst...

INSTALLATION OF PROPELLER The method of installation will depend on the type of propeller, and all instructions detailed in the appropriate AMM should be carefully followed; th

Long term goals behind artificial intelligence, Artificial Intelligence ...

Artificial Intelligence Artificial Intelligence is a typical science to describe, because it has fuzzy borders with, psychology, computer science, mathematics, philosophy, stat

Aeroengines - fluent problems, We are interested in the supersonic flow of...

We are interested in the supersonic flow of air through a convergent-divergent nozzle having a circular cross-sectional area, A, that varies with axial distance from the throat, x,

Aircraft radio installation licence and approval, AIRCRAFT RADIO INSTALLATI...

AIRCRAFT RADIO INSTALLATION (STATION) LICENCE AND APPROVAL 1. A radio installation licence is issued by the Department of Trade and Industry Radio Communications Agency , fo

Syntax and variable matlab, Syntax and variable in matlab The MATLAB ap...

Syntax and variable in matlab The MATLAB application is designed around the MATLAB terminology. The easiest method to perform MATLAB value is to type it in the Control Screen,

High rise buildings - fire protection engineering, High rise buildings: ...

High rise buildings: High rise buildings have their own particular requirements for fire safety and for fire fighting.  Means of escape rely on most people descending the stai

Synchro resolvers for high load, Synchro resolvers for high load The re...

Synchro resolvers for high load The receiver rotor is driven by an electric motor to a null position, i.e. the receiver coil will be aligned at 90 o  to the transmitter coil. A

Material science and engineeing, cite advantages of forming metal by extrus...

cite advantages of forming metal by extrusion as opposed to rolling

Mine Drainage Task, The purpose of this project is to design a pipeline and...

The purpose of this project is to design a pipeline and pumping system to dewater a mine. The production level is 500m below surface. Ore is fed through crusher chambers to the tra

Refrigeration, can liquid reciever determine amount f refrigerant charged i...

can liquid reciever determine amount f refrigerant charged into the system

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