It is the process to clean the surface to be painted by applying forced fine aggregate.
Acompressor will be used to develop the pressure 4 to 6 kg/cm2.
Ahopper will be filled by sand and to be connected with gun and hose nozzle assembly.
Askilled operator & gun man have to use this process.
The fine aggregates (sand) will be loaded in a special hopper and keep in closed condition
Ahose from compressor can carry 6kg/cm2 pressure of air will be connected at the bottom of hopper
Agun and hose assembly also connected in exit of hopper.Which will be sufficient length, so that it can reach where the area will be sand blasted?
The compressed air having 4 to 6 kg/cm2 pressure will carry the sand particle and forcedly apply the surface so that the rust foreign particle will be removed from the surface to be painted.
The gun will be handled safely and apply over the surface uniformly.
So, that the rust and all dust are removes by this process.
The humidity will be checked and the sand blasted will be done in sunny whether probably.
Within one hour the painting process will be started on the sand blasting area.
After sand blasting the surface of the pipe will be cleaned by pure air i.e without sand so that the dust everything will be removed properly.
The surface now will be free of dust and rust as well as the dry weather will the painting will carry out.
The painting will be done over the surface of pipe both inside and outside to avoid corrosion as well as erosion of bare pipes.
It will prevent rust formation from atmospheric contaminations
It looks very nice, so the color of paint will be chosen as good as possible.
ThePainting will be applied in dry season the humidity will be checked during painting.
There will be 3 coats normally recommended for the painting
1st Coat Zinc rich primer 100-150 microns, 2nd coat coal tar Epoxy 150-200 microns, 3rd coat coal tar Epoxy 150-200 microns.
For every coat we have to allow curing time at least 4 hours, So that the paint may set over the surface and bonding will be effectively
The selection of brand of paint will be chosen good brand as per its adhesive and cohesive properties.
In this method painting brush will be used to apply the painting, after painting the brush will be washed and kept for reuse.
In this method painting sponge roller will be used to apply the painting in this method the wastage may be related comparing brush painting.TheDFTwill be maintained after applying the paint by sample method.
In this method a compressor, hose and nozzle will be used to apply the paint.
The pressure will be 1.0 to 2.0 kg may be used.is is air less method i.e. the compressed air does not Th conduct with the paint sump during the spray.
The spray may applied uniformly and the thickness of paint will be maintained
This coating finish will be achieved depends of the operator skill and nozzle tip.
After dry of every coat the thickness will be checked by“ELCOmete”or“electronic coat meter”
This is the method same as inling of pipeICML(Inside cement mortar lining).
TheQty of paint as per the surface will be calculated and poured inside pipe during when it is rotating.
After poring paint, two operators may do the brush finish for both side of pipe when it is rotating.
After brush finished the pipe will be allowed to rotate at least 20 min. in speed condition.
For every coat of paint the pipe will be rotated independently. i.e. 1st coat 1 time spinning &IInd &IIIrd coat another time spinning. so we have to achieve the thickness of painting accordingly.
After drying i.e. setting or curing of paint we have to check the thickness byELCOmeter.
We can understand the qty of paint per coat by making of few trail runs.
The finishing will be achieved by time and speed of pipe spinning on the machine.
After spinning the pipes or to be kept for curing.
In this method we have to do the painting at inside first and out side next.The uniform deposition will be achieved by skill of operator and quality of paint.
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