Top drive drilling apparatus

1. A top drive well drilling apparatus designed to be suspended from a travelling block in a drawworks and laterally supported by a dolly running together with the well drilling apparatus along tracks or rails attached to a derrick, said drilling apparatus comprising:

at least one driving motor, one power transmission powered by the at least one driving motor, a drive shaft driven from the power transmission and designed to be connected to a drill string, load transferring means, and a torque arresting device attached to and depending from the power transmission, wherein

the load transferring means are in the form of a load frame that load relieves the drive shaft and the power transmission at the same time as it forms a central component which the other components are constructed around, and

the torque arresting device comprises a clamping device that is able to retain a stub shaft which includes one or more valves, which shaft stub, while it is held stationary by the clamping device, is pivotal about a horizontal axis through the clamping device for laying down towards a horizontal position by means of a hydraulic cylinder.

2. A top drive well drilling apparatus according to claim 1 , wherein the load frame is in the form of a structural element omitting any moving parts.

3. A top drive well drilling apparatus according to claim 1 , wherein the load frame carries the power transmission where the power transmission constitutes a component which is releasable from the load frame by means of releasable connecting means.

4. A top drive well drilling apparatus according to claim 1 , wherein the power transmission carries the at least one driving motor where each driving motor constitutes another component which is releasable from both the power transmission and the load frame by means of releasable connecting means.

5. A top drive well drilling apparatus according to claim 1 , wherein the power transmission carries the torque arresting device that constitutes another component which is releasable from the transmission by means of releasable connecting means.

6. A top drive well drilling apparatus according to claim 1 , wherein the connecting means are hydraulically operated bolts and nuts.

7. A top drive well drilling apparatus according to claim 1 , wherein the connecting means are manually operated bolts and nuts.

8. A top drive well drilling apparatus according to claim 1 , wherein the apparatus includes a swivel for transfer of mud or liquid from a stationary place to the rotating drill string, the swivel being connected to the drive shaft and forms together a swivel module that is releasable from the load frame by means of releasable connecting means.

9. A top drive well drilling apparatus according to claims 8 , wherein the swivel is further connected to and in fluid communication with the drill string via the stub shaft, the stub shaft having at least one internal safety valve and also at least one redundant valve.

10. A top drive well drilling apparatus according to claim 1 , wherein the apparatus includes a converting module for converting signals from analogue to digital format.

11. A top drive well drilling apparatus according to claim 1 , wherein the apparatus includes an elevator mechanism having an elevator for manipulation of drill pipes/pipe string.

12. A top drive well drilling apparatus according to claim 1 , wherein at least some of the components of the well drilling apparatus are designed, constructed and arranged as component modules, which by means of quick releasable connecting means connect the individual components/modules together.

13. A top drive well drilling apparatus according to claim 1 , in combination with said dolly laterally supporting said dolly including horizontally and vertically adjustable wheel sets.

14. A top drive well drilling apparatus according to claim 13 , wherein each adjustable wheel set is provided on a bracket having a mounting surface that is to be laid against an inclined surface on the frame of the dolly for adjustable fixation of the bracket to the frame.

15. A top drive well drilling apparatus according to claim 1 , wherein the torque arresting device further comprises activating mechanisms for operation of said valves within the stub shaft.