That's a great question and I'll do my best to answer it by covering the differences between the two.
The wet method uses water to cool the diamond abrasives. The water reduces friction and acts as a lubricant, eliminating any grinding dust.
The resin bonded grinding disks can melt at high temperatures. The water keeps them cool and increases their life span.
The wet process of polishing concrete creates a slurry on the surface which is a mixture of the grinding dust and the water.
The downside to this is it has to be cleaned up and disposed of as your grinding and polishing. This can slow productivity and create a mess inside finished homes and retail stores.
The upside to this is it keeps harmful silica dust out of the air (and your lungs) and the slurry can be recycled to used for other things like road mix.
Dry polishing doesn't use any water. New technologies in resin bonded grinding disks now allow them to withstand the heat and friction of the dry polishing process.
The polishing machine is equipped with a dust containment system (vacuum) that virtually eliminates all the dust and the mess.
This increases productivity and allows for concrete floors to be polished inside buildings without having to cover and clean everything when your done.
The downside is no vacuum system can capture 100% of all the dust created. Some harmful silica dust may be left on the floor. As people walk on it, and vacuum hoses or extension cords are dragged across it, the dust will get in the air.
Although both methods have their advantages and disadvantages, one method may not necessarily be better than the other. You'll have to decide which method will work best for your sutuation.
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