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

Fire safety management for clubs, Fire safety management for clubs: In...

Fire safety management for clubs: In clubs and other places where there is music being played, or other entertainment, it is important that the music (or other entertainment)

Railway inspections - fire safety management, Railway Inspections - fire sa...

Railway Inspections - fire safety management: Railway premises can be anything from small open air stations to large underground complexes and the fire safety measures that ar

Thermo electric thermometer, how thermoelecteric thermometer is contructed ...

how thermoelecteric thermometer is contructed and how it working

sweep effects, In the previous discussion, we investigated the static aero...

In the previous discussion, we investigated the static aeroelastic behaviour of straight (unswept) wings. These wings are characterised by an effective decoupling of wing bending a

Engine fuel control systems - aircraft engine, Engine fuel control systems:...

Engine fuel control systems: The thrust of a turbo jet is controlled by varying the amount of fuel that is burnt in the combustion system and in order to operate the safe tempe

Cell arrays matlab, Expertsmind.com offers  Cell Arrays matlab assignment ...

Expertsmind.com offers  Cell Arrays matlab assignment help In matlab, Cell arrays are just like frequent arrays in that they are "indexed" details of information, with an out

Operation research, what is the difference between stepping stone method an...

what is the difference between stepping stone method and the MODI

Offsets, functions of offset

functions of offset

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