Abstract: A method for controlling propulsion of a drilling rig. The drilling rig includes a right propulsion unit and a left propulsion unit and mutually independent speed control and a transmission for driving the right propulsion unit and the left propulsion unit. The transmission provides at least two gear states of a gear box. A propulsion speed is request for the right propulsion unit and for the left propulsion unit. A difference is determined between a requested propulsion speed of the right propulsion unit and the left propulsion unit. A suitable gear state is determined based on the determined difference. Also a computer program product including program code for a computer for implementing the method. A system and a drilling rig equipped with the system.

Abstract: A method for controlling propulsion of a drilling rig. The drilling rig includes a right propulsion unit and a left propulsion unit and mutually independent speed control and a transmission for driving the right propulsion unit and the left propulsion unit. The transmission provides at least two gear states of a gear box. A propulsion speed is request for the right propulsion unit and for the left propulsion unit. A difference is determined between a requested propulsion speed of the right propulsion unit and the left propulsion unit. A suitable gear state is determined based on the determined difference. Also a computer program product including program code for a computer for implementing the method. A system and a drilling rig equipped with the system.

Abstract: The present invention relates to a method for determining a variation of a flushing medium flow at a rock drilling apparatus, where a compressor (8;301) discharges a flow of pressurized gas, where said gas flow at least partially is used as flushing medium during drilling with a tool (3), wherein, during drilling, said flushing medium is led to said tool (3) for flushing away drilling remnants. The method includes to determine a rate of a pressure variation of said flushing medium, and generating a signal when said determined rate exceeds a first value. The invention also relates to a system and a rock drilling apparatus.

Abstract: The present invention relates to a control of a compressor (8) at a rock drilling apparatus, said rock drilling apparatus including a power source for driving a compressor (8) at a rock drilling process, said compressor (8) being arranged to operate according to a first mode and according to a second mode, wherein, in said first mode, the work produced by the compressor (8) is arranged to be controlled by controlling the rotation speed of said compressor (8), and wherein, in said second mode, the work produced by the compressor (8) is arranged to be controlled by controlling the air flow at the compressor inlet.

Abstract: The present invention relates to a method for controlling a power source (9) at a rock drilling apparatus, said power source (9) being arranged to drive at least a first load (8, 10, 15) at the rock drilling apparatus, wherein said first load (8, 10, 15), in operation, provides power to a first consumer (11, 21), and where the power that can be delivered by- said first load (8, 10, 15) depends on the rotation speed of the power source. The method includes, by means of a representation of said first consumer (11, 21), determining a power demand of said first consumer (11, 21), and based on said determined power demand, determine a rotation speed demand of said first load (8, 10, 15). The rotation speed of said power source is then controlled based at least on said determined rotation speed demand of said first load (8, 10, 15 ). The invention also relates to a system and a rock drilling apparatus.

Abstract: The present invention relates to a method for determining a variation of a flushing medium flow at a rock drilling apparatus, where a compressor (8;301) discharges a flow of pressurized gas, where said gas flow at least partially is used as flushing medium during drilling with a tool (3), wherein, during drilling, said flushing medium is led to said tool (3) for flushing away drilling remnants. The method includes to determine a rate of a pressure variation of said flushing medium, and generating a signal when said determined rate exceeds a first value. The invention also relates to a system and a rock drilling apparatus.

Abstract: The present invention relates to a method for controlling a power source (9) at a rock drilling apparatus, said power source (9) being arranged to drive at least a first load (8,10,15) at the rock drilling apparatus, wherein said first load (8,10,15), in operation, provides power to a first consumer (11,21), and where the power that can be delivered by- said first load (8,10,15) depends on the rotation speed of the power source. The method includes, by means of a representation of said first consumer (11,21), determining a power demand of said first consumer (11,21), and based on said determined power demand, determine a rotation speed demand of said first load (8,10,15). The rotation speed of said power source is then controlled based at least on said determined rotation speed demand of said first load (8, 10, 15 ). The invention also relates to a system and a rock drilling apparatus.

Abstract: The present invention relates to a control of a compressor (8) at a rock drilling apparatus, said rock drilling apparatus including a power source for driving a compressor (8) at a rock drilling process, said compressor (8) being arranged to operate according to a first mode and according to a second mode, wherein, in said first mode, the work produced by the compressor (8) is arranged to be controlled by controlling the rotation speed of said compressor (8), and wherein, in said second mode, the work produced by the compressor (8) is arranged to be controlled by controlling the air flow at the compressor inlet.