Apparatus
Le chatelier mould
The mould comprises of a very minute split cylinder made out of spring brass or some other compatible metal of 0.5mm density creating of a mould 30mm interior diameter and 30mm height. On both sides of the split, they are joined to the indicators with pointed ends A-A- the space from these ends to the focal point of cylinder being 165mm. The mould has to be maintained in favorable condition with the jaws not exceeding 0.5mmapart.
Procedure
(i) Create a cement paste like in the consistency test with 0. 78 times the liquid necessary to create a paste of average constancy.
(ii) Now put the prepared cement paste in the Le- chatelier mould with very delicate care in order to put the edges of the mould mildly connected in the process of operation.
(iii) In the third process, keep the mould with another piece of glass plate and then apply a small weight on the top of the cover plate.
(iv) Partially immerse the entire assembly straightaway in water at approximate temperature of 27o+-2oC and let it be submerged for a whole day.
(v) Now take out the assembly once again in water at 27+/- 2 deg C.
(vi) Repeat the process of submerging it again in water at 27 +/- 2 deg C
(vii) Heat the water to boiling for around 30 minutes and let it be boiled for another 3 hours. The assembly has to be completely immersed in water in the midst of this procedure.
(viii) Now detach the mould from water and leave it for cooling at the temperature of 27 +/- 2 deg C
(ix) Calculate the space amongst the indicator points (B)
Calculation
Expansion = B-A =
Result
Expansion=
IS specification
Interference
