Drill rig and method for controlling a fan therein

1. A method for controlling regulation of cooling demand of a drill rig ( 1 ) having an engine house ( 5 ) including an engine ( 9 ), at least two cooling elements ( 12 ), at least one fan ( 13 ), a control unit ( 15 ) to control i) the fan ( 13 ) and ii) the cooling demand in the cooling elements ( 12 ), the method comprising the steps of:

determining the cooling demand of each cooling element ( 12 ), wherein at least one cooling element ( 12 ) is equipped with a safety thermostat ( 21 ) located at one end of the cooling element ( 12 );

weighting together the determined cooling demand;

by using the control unit, controlling a rotation speed of the fan ( 13 ) based on said weighting together the determined cooling demand; and

operating the safety thermostat to prevent overcooling by not allowing fluid to circulate in said at least one cooling element.

2. The method according to claim 1 , wherein the at least one fan ( 13 ) is controlled based on the cooling demand of the cooling element ( 12 ) that has the greatest cooling demand.

3. The method according to claim 2 , wherein the rotation speed of the fan ( 13 ) is controlled based on the cooling demand of the cooling element ( 12 ) that has the greatest cooling demand.

4. The method according to claim 1 , wherein the rotation speed of the fan ( 13 ) is controlled based on the cooling demand of the cooling element ( 12 ) that has the greatest cooling demand.

5. The method according to claim 1 , wherein an ambient temperature is measured in order to determine the cooling demand in each one of the cooling elements ( 12 ).

6. A method for controlling regulation of cooling demand in a drill rig ( 1 ), comprising the steps of:

adapting at least one cooling element ( 12 ) to regulate the cooling demand of the drill rig ( 1 ) by using at least one fan ( 13 );

determining the cooling demand by measuring an ambient temperature of said at least one cooling element ( 12 ) associated with a safety thermostat ( 21 ) arranged at one end of the cooling element ( 12 );

comparing the determined cooling demand from each cooling element ( 12 ) to control a rotation speed of said at least one fan ( 13 ); and

operating the safety thermostat ( 21 ) to prevent overcooling by not allowing fluid to circulate in said at least one cooling element ( 12 ).

7. A method for controlling regulation of cooling demand in a drill rig ( 1 ) using at least one fan ( 13 ), comprising the steps of:

determining the cooling demand of each cooling element ( 12 ); and

comparing the cooling demand of each cooling element ( 12 ) together to control a rotation speed of each fan ( 13 );

wherein at least one cooling element is equipped with a safety thermostat ( 21 ) located at one end of the cooling element ( 12 ) to prevent overcooling by not allowing fluid to circulate in the cooling element,

wherein said at least one fan ( 13 ) is arranged to co-operate with each cooling element ( 12 ), and each fan ( 13 ) is controlled based on weighting together the cooling demand of each cooling element ( 12 ).

8. A control arrangement for cooling demand in a drill rig, comprising:

a control unit ( 15 ) arranged to control a rotation speed of at least one fan ( 13 ) based on the cooling demand;

a cooling element ( 12 ) arranged for fluid to circulate between the cooling element ( 12 ),

wherein an ambient temperature of the cooling element ( 12 ) is measured for the cooling demand,

wherein said at least one fan ( 13 ), in operation, creates an air flow through the cooling element ( 12 ) when the cooling demand is determined in the drill rig; and

a safety thermostat ( 21 ) arranged to prevent overcooling by not allowing circulation of the fluid in each cooling element ( 12 ), wherein at least one of the cooling element ( 12 ) is associated with the safety thermostat ( 21 ) located at an output of the cooling element ( 12 ).

9. The control arrangement according to claim 8 , wherein the cooling demand of the cooling element ( 12 ) has the greatest cooling demand.

10. The control arrangement according to claim 9 , the drill rig comprises at least four cooling elements ( 12 ).

11. The control arrangement according to claim 9 , wherein the cooling element ( 12 ) includes a engine water cooler, a charge-air cooler, a hydraulic-oil cooler and a compressor-oil cooler.

12. The control arrangement according to claim 9 , the drill rig is operated by an internal combustion engine which comprises a compressor ( 10 ) and a hydraulic-oil pump ( 11 ).

13. The control arrangement according to claim 8 , the drill rig comprises at least four cooling elements ( 12 ).

14. The control arrangement according to claim 8 , wherein the cooling element ( 12 ) includes a engine water cooler, a charge-air cooler, a hydraulic-oil cooler and a compressor-oil cooler.

15. The control arrangement according to claim 14 , wherein said at least one fan ( 13 ) is arranged to co-operate with each cooling element ( 12 ).

16. The control arrangement according to claim 15 , wherein the hydraulic-oil cooler and the compressor-oil cooler constitute a first group cooling element ( 12 ), and the engine water cooler and the charge-air cooler constitute a second group cooling element ( 12 ).

17. The control arrangement according to claim 15 , wherein said at least one fan ( 13 ) is associated with one of the first and second group cooling elements ( 12 ) based on weighting together of the cooling demand of each group cooling element ( 12 ).

18. The control arrangement according to claim 8 , wherein the drill rig is operated by an internal combustion engine which comprises a compressor ( 10 ) and a hydraulic-oil pump ( 11 ).

19. The control arrangement according to claim 8 , wherein the drill rig comprises sensors ( 16 - 20 ) in order to measure the ambient temperature corresponding the cooling demand of each one of the cooling elements ( 12 ).