The attacks are the latest in a surge in violence that security forces have failed to curb, despite carrying out major operations against militants said to have resulted in scores of arrests, including 82 yesterday.
In the deadliest attack today, a car bomb exploded in the northern province of Kirkuk, killing three police.
Bombings also killed a soldier, a Sahwa anti-Al-Qaeda fighter and two civilians in Salaheddin province, north of the capital, while gunmen shot dead a former soldier and a civilian in the northern province of Nineveh.
The attack halted exports via the pipeline, a senior official from the North Oil Company said, adding that production was still continuing, but the oil was being stored.
Repairing the pipeline, which runs from the northern Iraqi oil hub of Kirkuk to the port of Ceyhan in Turkey, is expected to take between one and three days, the official said.
The attacks came a day after bombs targeting a cafe, a football field and a market in areas north of Baghdad killed 28 people.
Authorities have repeatedly highlighted security operations -- among the largest since US forces departed in December 2011 -- which they say have led to the killing or capture of many militants.
But whatever gains the operations have made, they have failed to stop the bloodshed.
Violence in Iraq has increased markedly this year, with analysts saying the upsurge is driven by anger among the Sunni Arab minority that the Shiite-led government has failed to address, despite months of protests.