Fracking involves injecting water, sand and chemicals deep underground to break apart rock and access deposits of shale oil and gas. The fracking boom has led to jobs, and billions in royalties and profits, but critics say the process can contaminate water supplies.

Petro-king chairman Wang Jinlong says the buyout of Sheraton will boost the services provider's profit margin. Photo: Edward Wong

Petro-king plans HK$381m upgrade

Termbray Petro-King Oilfield Services, which recently agreed to take over its tool- and equipment-making subsidiary in Singapore, plans to spend 300 million yuan (HK$379 million) in the next two years to quintuple its annual capacity in tools for fracturing rock formations to enhance oil and gas production.