Qatar National Cement Company (QNCC) has decided to use Sandvik DX700 top-hammer crawler drill rig for its latest limestone quarry
The drill rig operating at Qatar's largest limestone quarry, near to Doha, is equipped with Sandvik drill bits, rods and shank adapters to bore to depths of 75ft (22 m).
"Our total output is 5 million tonnes per year, and following a downturn in Qatar's construction sector we are now looking at a lengthy period of high demand with many new projects underway and upcoming, so we need a high-productivity machine that is also reliable," said Mr Ahmed El-Khazien.
The rig, drill bits and other equipment have been supplied by Sandvik's distributor in Qatar, Q-Fab, which has a maintenance contract with QNCC. Sandvik's service agreement covers both 250-hour servicing and breakdown and repair services, both of which are carried out by Q-Fab. QNCC staff carry out routine maintenance.
Training has been provided for Q-Fab's service engineers, and three employees of QNCC who operate the rig in shifts.
"We are using the Sandvik rig to drill 3.5-inch holes down to the depth of the quarry floor, which is between 72 and 75 ft (22 m) below the surface," El-Khazien said.
The DX700 is a hydraulic, self-propelled, self-contained and crawler-based surface rig that has a standard drilling coverage of 17.6 m2 and which uses a Rock Pilot drilling control system that ensures maximum penetration and rock tools service life as well as straight holes.
At the QNCC quarry, the DX700 is using Sandvik 89 mm RT300 Uniface Retrac drill bits - a newly launched range of threaded button bits that use one super grade of cemented carbide throughout and a universal face design.
"In nine months of working we have had no breakdowns, and the DX700 is proving to be very reliable and productive," concluded El-Khazien.