Bien Hoa Building Materials Production and Construction Company (BBCC) have received a two-year extension for their granite quarry in Bien Hoa, some 32km east of Ho Chi Minh City.
The quarry, which covers an area of 20ha and produces around 8 million m3 of aggregates per annum, was reopened in 2007 and scheduled to close in 2010, but because of the quality of its rock and its importance in meeting local demand for construction and road aggregates, this has now been extended to 2012.
Playing a key role in extracting the high-quality granite, which has a compressive strength of 1,500–1,700kg/cm2, are two Sandvik drill rigs and three Sandvik breakers.
For oversize boulders, BBCC rely on a Sandvik BR4510 breaker fitted to a 35-tonne Cat 375 ME excavator. Weighing almost four tonnes, the BR4510 produces 9,000J and has an impact rate of 350-550 blows/min.
The other two breakers (older BR4510 units) are used on a rotational basis during maintenance periods.
According to Mr Ho Thanh Thuy, BBCC’s site technical supervisor, the BR 4510 makes light work of even the largest granite boulders at the site.