Tool Preparation and Cleaning
Just as you wash and prep ingredients before cooking, you need to get your "gear" ready before connecting the joints:
Specialized Wrench: Select a hydraulic wrench that matches the joint size to prevent slipping.
Wire Brush: Thoroughly remove grit, dirt, and old sealant from the thread surfaces.
Sealant: Use a high-pressure-resistant thread lubricant; applying enough to cover 80% of the threads is sufficient.
Thread Alignment Techniques
This step is a test of visual precision, much like aligning a bolt with a nut:
Initial Alignment: Support both ends of the drill pipe levelly with both hands, ensuring the axes are perfectly aligned.
Slow Rotation: Rotate counter-clockwise (backwards) for two full turns until a "click" is heard, confirming the thread's starting point.
Manual Threading: Screw in clockwise by hand for 3–5 turns; ensure there is no binding or resistance before using tools.
Precise Torque Control
The final step is like inserting a wine cork-applying too much force causes an overflow:
Staged Loading: Apply torque in three incremental steps, reaching 30%, 60%, and 100% of the preset value respectively.
Alignment Check: Mark an alignment line across the threads; the final offset should not exceed one thread pitch.
Back-off Test: Loosen the connection by 5° and then re-tighten it to eliminate any potential residual stress.
