Gabbro demand met by Gibca and Sandvik

Gibca Crushing and Quarry Operations is supplying large quantities of armour rock for Dubai’s Palm Island projects. Gibca Crushing at Kadrah, some 25 km east of Dhaid, is the biggest among a number of quarries in the region to recognise the performance provided by its Sandvik Tamrock hydraulic crawler drills and Sandvik rock tools working in this highly abrasive rock. Gibca received its first licence to excavate gabbro from the local municipality 30 years ago in a riverbed retrieval application of the wadi over a 4 km2 area.

As the riverbed source dried up and demand for gabbro increased, Gibca opened the first of two quarries in 1989 placing an order for its first Tamrock hydraulic drill, a CHA550. With continuing demand, Gibca took further deliveries of Tamrock rigs with a CHA660 in 2001 and a CHA700 late last year. Today with all three Sandvik Tamrock rigs working, the high production CHA700 is taking the lion’s share with its larger 89 mm diameter holes.

The CHA700 is a hydraulic top hammer crawler drill designed for 64–102 mm diameter blastholes using T38, T45 and T51 extension drill steels. Its robust build is well suited to the demanding terrain of the Kadrah quarry. It is equipped with an HL710 hydraulic rock drill, chain feed, rod handling system, telescopic boom and powerpack, all mounted on an oscillating FL6 type undercarriage.

The crosswise mounted powerpack – engine, air compressor and hydraulic pumps – is mounted at the rear of the rig to balance the weight of the boom, feed and rock drill.  This keeps the body of the drill short and guarantees good stability. The CHA700 is powered by a Caterpillar 3056E diesel engine, which meets TIER II and STAGE II emission requirements and offers lower fuel consumption.

All three rigs are fitted with Sandvik extension drilling tools.  The CHA700 is using 89 mm diameter retrac button bits and T51 MF-extension rods. The two older rigs are also using Sandvik rock tools including 64-mm retrac bits and T38 MF-extension rods.


According to Quarry Manager, Gulam Mohammed, the hydraulic drills and Sandvik drill steels are proving to be a winning combination, providing exceptional service in difficult conditions. “The secret is,” he adds, “we take very good care of our equipment, maintaining it correctly and regularly.” This includes regrinding the Sandvik bits. “From day one we recognised the importance of grinding to at least double the life of the bits and extend the life of the rods,” he added. Gibca undertakes its own grinding on-site on a weekly basis, minimally two times on each bit and according to Gulam Mohammed, generally three times. He says, “We hope to get between 700 – 800 drill m/bit but it is all dependent on the hardness of the rock.”