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

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

Capital budgeting decisions, Capital Budgeting Decisions The most important...

Capital Budgeting Decisions The most important function of a finance manager is the efficient allocation of its capital. The investment decision of a firm is termed as capital budg

Aerofoil theory and the axial flow compressor, Aerofoil theory and the axia...

Aerofoil theory and the axial flow compressor  The blades of the axial flow compressor are aerofoils and as such behave in a similar way to aircraft mainplanes and propeller bl

Cash Conversion Cycle, The need for working capital to run the day-to-day b...

The need for working capital to run the day-to-day business activities cannot be overemphasized. We will hardly find a business firm which does not require any amount of working ca

Modified accelerated cost recovery system , Modified Accelerated Cost Recov...

Modified Accelerated Cost Recovery System (MACRS) Although SLN is the most commonly used depreciation method in the U.S. for purpose of financial reporting, MACRS is the only

Continuous casting, Continuous Casting : In essential, the process consist...

Continuous Casting : In essential, the process consists of pouring molten metal into a short vertical metal die or mould (at a controlled rate), which is open at both ends, coolin

Structural engineering, The closed form solutions for ?max and Mmax are giv...

The closed form solutions for ?max and Mmax are given on page 16.1-276 for several axial loads. Figure C-C2.2 summarizes the results for the first benchmark problem and Figure C-C2

Diffusion, distingush between short range and long range diffusion

distingush between short range and long range diffusion

Means of escape - place of safety, Means of escape - place of safety: ...

Means of escape - place of safety: The means of escape in a building are often supplemented by a fire warning system that may or may not include automatic detection, depending

Grid generator, Grid Generator The grid generator of FP sets up a compu...

Grid Generator The grid generator of FP sets up a computing grid in a transform space that consists of the interior of a unit length circular cylinder of unit radius, and compu

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