Though there are a number of practices involved, Kamani Foundry follows the following systems: -
3 Part A-B-C- system: Where’s’ part is Resin, while part ‘C’ is a catalyst (or Activator) and part ‘B’ is a Hardner. The quantities Mixed very depending on the type of Pettern/Mould and the bench life needed for the same. General proper GMS followed are:
Part ‘A’: - 2% of the sand quantity.
Part‘B’: - 8% of Part ‘A’ and
Part ‘C’: - 15% to 20% of Part ‘A’:
First part ‘A’ and Part ‘C’ are mixed along with sand in the sand mixer for about 90 second to 2 minutes and then Part ‘B’ is added and further mixed for one minute. Immediately after this, sand a discharged from the mixer and put in the core box. The sand mix is rammed by way of hand rammers and leveled on the core box. After allowing the sand to harden slightly, the core is stripped from the Pettern and allowed for ageing further.
2 – Part System: In this systems Resin and activator are made in a single from and after mixing it with sand for an initial period of about 2 minutes, Hardner is added and mixed for another one minute. Then the sand mix is put in the core after allowing the sand to harden slightly, the core is stripped from the Pettern and allowed for ageing further. box.
Single Part System: Here, it is an air setting chemical is mixed with sand for a minute to 90 seconds and then mould made as a for with further procedure.
|Here the painting is done essentially in water base graphite paint prepared in the same as mentioned in A1 but left over for a longer time for drying.|
|Cores are also painted according to the type, in either water base or thinner base, paint prepared by mixing graphite ready mix paste or powder in water or thinner as the case may be and then spray paints. |
|(a)||Oil Sand Cores : |
Generally water base graphite paints are as spray-painted and the torched or heated in the oven at a temperate of 105oC for proper drying.
|(b)||CO2 Sodium Silicate Cores : |
Here the cores are essentially painted with in inner base painted prepare as mentioned in b1 and then ignited for proper drying.
|(c)||NO BAKE SYSTEM CORE : |
Here the painting can be water base or spirit base graphite prepared as mentioned in A1 or B1 and then as spay painted – torched or ignited as the case may be.
|(d)||SHELL CORE : |
These are generally painted in water base Zircon mix paints, prepared in the same way as graphite paints but is important that these cores are dried completely after painting.
|However in the all above cases, the moulds and cores are ensured for proper drying, if necessary torching before after core setting.|