BUMA RCDs are well proven in India and 85 per cent of the RCD rigs working in India are from BUMA.

Surajit Mukherjee, Managing Director, Suretech Infrastructure Pvt Ltd.

Mumbai based Suretech Infrastructure Pvt Ltd is the authorised dealers of BUMA CE CO. Ltd of Korea for its Reverse Circulation Drilling (RCD) rigs in India. BUMA CE specialises in manufacturing and supplying RCD rigs, which are used for drilling large diameter piles in hard rock.

RCD, also known as air-lift system, compressed air is injected into the drill pipe below water level just above the drill bit. This reduces the density of the internal water column and starts the circulation. The mixture of water, air and cuttings are then flushed out through the drill pipe into settling tanks.

“RCD machine is essential for the foundation drilling of large diameter (1,000 – 4,000 mm) pile. This equipment is used for drilling a borehole through soft and hard rock layers for the construction of foundation,” informs Surajit Mukherjee, Managing Director, Suretech Infrastructure Pvt Ltd.

There are two types of drill string (drill pipe), according to the internal pipe diameters, NW200 (200 mm) and NW300 (300 mm). NW200 drill pipe can be used upto RCD R1820 because of handling torque limit, mainly upto drilling diameter of 1.5 metres, NW200 drill pipe is recommended.

Basic Drill String
In order to prevent buckling in the bottom part of casing and for better verticality, basic drill string is required. The basic drill string is composed of drum stabiliser, heavy duty space pipe, heavy duty stabiliser and reducing pipe.