UAE’s Technical Drilling and Blasting Co standardise on special new rock tools
Drill and blast contractor Technical Drilling and Blasting Co standardises on Sandvik rock tools for its fleet of drill rigs operating across Fujeirah; providing quality gabbro aggregates.
The Emirate of Fujairah continues to be the regions ‘bread basket’ for construction projects in Dubai and Abu Dhabi. And, with many neighbouring Gulf countries banning quarry operations, its gabbro – based aggregates and rock armour for breakwaters are equally in high demand.
Rocks
Recognised as one of the worlds hardest rocks, gabbro with a typical density in excess of 3 t/m3. a crushing factor of 10 and a 61% silica content, demand is still high for this type of rock as it is used for both aggregates and offshore building projects.
Every hour of each day, a continuous team of trucks make the journey from the dozens of quarries in the Hajjar Mountains to the projects across the UAE.
With blasting strictly regulated across the Emirate, five companies specialise in drill and blast contracting in varying degrees for the quarrying sector.
Market leader Technical Drilling and Blasting, specialising virtually 100% in quarry activities, handles contracts for around 24 quarries in Fujairah.
The company’s Technical Manager; ‘Bill’ Armstrong confirmed that Technical Drilling and Blasting has a fleet of 16 surface top hammer drills and two down the hole drill rigs including nine Sandvik rigs which are proving ideal in development and difficult access areas of the quarries.
According to Project Manager, Alok Ojha, the key to much of the companies’ success has been the operational life and productivity of its Sandvik rock tools; all ordered through local distributor Dynatrade.
“Initially we used rock tools from the respective rig manufacturer but trials soon found that the Sandvik rock bits and rods were providing 100% longer operational life”.
He continued, “for example, we were using 60 rods which were continually ‘snapping’ compared with 30 Sandvik rods in the same conditions.”
And, for the drill bits, the life expectancy was even greater, as much as three times with Sandvik Retrac bits.
According to Bill Armstrong, generally in the hard rock conditions we are getting 700-800 drill metres/bit and upto 2000 in softer conditions.
Technical Blasting and Drilling carry out on-site regrinding after the first 400m with a second regrind after another 200 m.
Blasting
Each blast site is thoroughly surveyed with extensive details of each drill hole recorded. Blasts are planned weeks in advance and the explosives ordered.
UAE police and security witness all blasting operations and carefully monitor the explosives used.
The growth in demand over recent years put extra strain on the police forces resources and Technical Drilling and Blasting has been negotiating with the local authorities that a change in restrictions would help.
Until recently only 2 blasts at a maximum of 3t each day on a single site could be undertaken. Technical Drilling and Blasting was able to demonstrate that a single blast of 10t made everyone’s life easier and allowed the police and other authorities to visit more sites without taking any extra time.
Today, Bill is actively trying to increase the 10t limit to streamline the process even further.
In a typical quarry development, Technical Blasting and Drilling use a combination of the Sandvik rig and tools to supply around 65,000m3/month.
“It should be more but many of the quarry managements are poor at planning” said Bill, but confirming that in the better months upto 80,000m3 is supplied.
“This” he elaborated, “is achieved working 10 hour shift over six working days with a 4 inch holes in hard rock.”