Sandvik ... producing quality aggregates.

Having supplied armour rock for Palm Jumeirah and Palm Jebel Ali, Gibca, a leading supplier of quality aggregates and rock armour in the region, is currently supply its product for the giant Palm Deira, under a contract that is expected to last for another three years.

The largest of the three Palms, the Palm Deira will extend seawards for a distance of nine miles and includes a 13-mile-long outer crescent seawall. When completed in 2009, it will provide 7,000 residential homes and a marina.
Gibca Crushing and Quarry Operations’s customers include Al Nakheel, SS Lootha, Emirates Stone, Dafco, Keir Dubai and Barada Transport.

Construction boom
As the construction boom continues in Dubai, contractors are increasingly seeking quality aggregates from local quarries, particularly for asphalt and concrete production from gabbro – considered to be the region’s toughest rock. Featuring a density up to 2.9 tonnes/cu m and an aggregate crushing value of 13, the rock – found exclusively around Fujairah and Kadra – is highly abrasive and has up to 50 per cent silica (SiO2) content.
In addition to supplying large quantities of armour rock for the Palm projects, Gibca Crushing and Quarry Operations is also supplying aggregate and sand for Dubai’s asphalt road projects, readymix concrete companies and block factories.

Quarry operation
Its quarry 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 sq km area.
As the riverbed source finished and demand for the gabbro increased, Gibca opened the first of two quarries in 1989 placing an order for its first Tamrock hydraulic drill, a CHA550. With the continuing demand for increased production, Gibca took further deliveries of Tamrock rigs with a CHA660 in 2001 and a CHA700 late last year.
Today, with all three rigs actively drilling, the high-production CHA700 is handking the lion’s share with its larger 89 mm diameter holes.

Tamrock CHA700
The CHA700 is a hydraulic top hammer crawler drill designed for 64 to 102-mm diameter blast holes in construction and quarry applications using T38, T45 and T51 (11/2”, 13/4” and 2”) extension drill steels.
“Its robust build makes it eminently suited for the demanding terrain of the Kadrah quarry,” says a spokesman for the Finland-based Sandvik Tamrock. “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 and longer service life than conventional diesel engines.
“The drill is fitted with a complete safety and monitoring system for easy operation and fast maintenance.”
All three Sandvik Tamrock 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 the 64 mm diameter retrac bits and T38 MF-extension rods.
The quarry operates four benches with heights varying between 10 m and 12 m. On average, Gibca blasts twice a week over two areas of the quarry and produces 4 million tonnes per year (tpy) of different types of armour rocks and aggregates. Gibca is also planning to increase its production up to 5 million tpy in the near future,” says recently-appointed general manager, Engineer Ayman Al Hadidi.
According to quarry manager, Gulam Mohammed, the Tamrock 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 grinding 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 says. Gibca undertakes its own grinding on-site on a weekly basis, at least two times on each bit and according to Gulam Mohammed, generally three times.
He says, “We hope to get between 700 and 800 drill m/bit but it is all dependent on the hardness of the rock.”
Additional after-care back-up is also provided by the local dealer, Dynatrade.
Gibca was formed in 1975 and included a quarry and crushing division. Today, it has than 30 companies in the Gibca Group, including hotels, resorts, banks, Alico aluminium products, casting industry, Arabian Profiles, Tekab, glass products and air conditioning division. The quarry and crushing operation also remains one of the most active divisions among the group.