Desander is the second phase of drilling fluids process. They are also centrifugal device but removing sand or bigger particles from drilling fluid to prevent abrasion of the pumps. They are used to separate sand from drilling fluids which is mixed with drilling muds and big articles. During drilling process mud is being poured from inlet and is getting deeper. when the vortex in the hydroclone running, the water spray from a pipe and the mud ,soil,big articles subside down the outlet. That is the recycling of mud in order to separate water from mud and get a clean water that will be used in next excavations.