SANTIAGO, May 23 (Reuters) - Chile president Sebastian Pinera has tapped Gerardo Jofre to stay on as state miner Codelco's chairman until May 2017, the world No.1 copper producer said in a statement on Thursday. Conservative Pinera has also named civil engineer Blas Tomic Errazuriz to Codelco's nine-man board. He replaces Jorge Bande, Codelco added. Codelco, which produces roughly 11 percent of the world's red metal, is battling slumping ore grades in its tired deposits, soaring costs and an uptick in labor unrest as it fights to meet ambitious expansion targets. The miner plans to propel production to a record this year, boosted by its new slice of the coveted Los Bronces deposit and the launch of its Ministro Hales mine. Its previous record was the 1.796 million tonnes of red metal it mined in 2011.