Hi Manu, It is Direct Mud Circulation pile where water jet is let through the piling chiesel which comes out from bottom with Mud.
In DMC Pile Foundation the bentonite suspension is pumped into the bottom of the hole through the drill rods and it overflows at the top of the casing. The mud pump should have the capacity to maintain a velocity of 0.41 to 0.76 meters per second to float the cuttings.

Hope that solves your query,
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Thanks & Best of Luck!!