Controlled expansion of rock bolt

1. A method for manual installation of expandable rock bolts by pressurisation, including manual connection of a pressure source to a rock bolt to be expanded, characterised in that the method comprises the steps of:

an operator starting a sequence whereby the rock bolt is pressurised to a predetermined pressure, and

ensuring by means of said sequence, and by an apparatus comprising a control system comprising means for ensuring that said predetermined pressure is held during a predetermined period of time, that the predetermined pressure is kept for a predetermined period of time.

2. Method as claimed in claim 1 , wherein a signal is given off when the sequence is successfully performed.

3. Method as claimed in claim 2 , wherein a signal is given off when the sequence has not been successfully performed.

4. Method as claimed in claim 2 , wherein an error message is given off when the sequence has not been successfully performed.

5. Method as claimed in claim 2 , wherein a timer is cleared if the predetermined pressure during the predetermined period of time falls below a prescribed pressure level, and is further restarted when the prescribing pressure level is reached again.

6. Method as claimed in claim 1 , wherein a signal is given off when the sequence has not been successfully performed.

7. Method as claimed in claim 6 , wherein an error message is given off when the sequence has not been successfully performed.

8. Method as claimed in claim 1 , wherein an error message is given off when the sequence has not been successfully performed.

9. Method as claimed in claim 1 , wherein a timer is cleared if the predetermined pressure during the predetermined period of time falls below a prescribed pressure level, and is further restarted when the prescribing pressure level is reached again.

10. Method as claimed in claim 1 , wherein a chuck is used for installation does not release its grip of a rock bolt before the predetermined period of time has elapsed.

11. Method as claimed in claim 1 , wherein the starting of the installation requires action from an operator during a certain determined period of time before the sequence is started.

12. A control system for connection to a pressure source for manual installation of expandable rock bolts by pressurisation, characterized in that the control system ( 7 ) comprises:

means for ensuring that a rock bolt is pressurized to a predetermined pressure, and

means for ensuring that said pressure is held during a predetermined period of time.

13. Control system as claimed in claim 12 , wherein said means for ensuring a pressure comprises a timer arranged to determine the duration of the predetermined pressure.

14. Control system as claimed in claim 13 , wherein the timer is arranged to be cleared if the desired pressure during a predetermined period of time falls below a given pressure level, and further arranged to be restarted when the given pressure level is again reached.

15. Control system as claimed in claim 12 , wherein the the control system ( 7 ) comprises a reset button for enabling interruption of the installation.

16. Control system as claimed in claim 12 , wherein the control system ( 7 ) comprises a counter counting the number of correctly installed rock bolts.

17. Control system as claimed in claim 12 , wherein the control system ( 7 ) comprises means arranged to give of f a signal when the installation has succeeded.

18. Control system as claimed in claim 12 , wherein the control system ( 7 ) comprises means arranged to give off a signal when the installation has not succeeded.

19. Control system as claimed in claim 12 , wherein an error message is given when the sequence has not been performed successfully.

20. An apparatus for installing an expandable rock bolt by pressurization, said apparatus comprising a pressure source and means for manual coupling to an expandable rock bolt, characterized in that the apparatus comprises a control system ( 7 ) as claimed in claim 12 .