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Stabilizing Tools |
Essentially they centre the BHA in the hole. The basic types are rotating and non- rotating. In soft rock it can gauge the hole. The rotating type has blades that are spiraled around the body. The blades can be integral, namely molded onto the body, welded to the body or fastened to the body by pins or some mechanism.
There are sleeve type stabilizers that can be screwed onto the body. Short stabilizers can pivot and allow bending motion. This would facilitate their use in a directional assembly. Longer stabilizers or stacked short ones prevent bending moments from developing. Such an assembly would be locked up.
(Mitchell 1995)
Three basin types:
- Rotating blade
- Non-rotating blade
- Rolling cutter reamer
Rotating Blade – can be either straight or spiral. They ma be shop or rig repairable.
Shop repairable – they are integral welded or shrunken sleeve. These tools are recommended for soft formation especially in the case of the welded bladed stabilizer.
Rig repairable – they have a replaceable sleeve mechanism or replaceable wear pads. They have a fairly good reaming ability.
Rig replaceable non-rotating – this is the safest tool to run from a wash over sticking stand point. Good for hard formations has no reaming ability and the sleeve life is short in rough wellbores. (Smith International 1977)
Bibliography
Mitchell, Bill. Advanced Oilwell Driling Engineering. Richardson, Texas: Society of Petroleum Engineers of the AIME, 1995.
Smith International. Drillco Drilling Assembly Handbook. Houston, 1977.
