Mining giant BHP Billiton has trimmed its full-year iron ore production guidance after being forced into unexpected dumper car maintenance.
The company now expects to produce between 272 million tonnes and 274 million tonnes for the 2018 financial year, compared to previous guidance of between 275 million and 280 million tonnes.
Third-quarter iron ore production was 57.7 million tonnes - up eight per cent on the prior corresponding period - bringing the total for the nine months to March to a record 175 million tonnes.
But third-quarter production slipped six per cent form the previous quarter because of the unreliable dumper cars needing maintenance to improve availability and performance.
That remedial work on the dumper cars should help the company increase annual production at its Port Hedland operations to the 290 million tonnes for which it already has regulatory approval.
Third-quarter copper production doubled from the prior corresponding period, and increased six per cent from the December quarter, thanks to the start up of the Los Colorados Extension project in September.
BHP shares rose 93 cents, or 3.1 per cent, to $31.00 by 1031 AEST on Thursday, supported by surging commodity prices.
RBC Capital Markets analyst Paul Hissey said he rated BHP at fair value, on par with rival Rio Tinto.
"The 2018 March quarterly result was softer than our estimates across the board, with the exception of the copper group," he said.
