Special Spiral Drilling Collar (Drill Pipe, Drilling Rob)

Oil-Field Special Drilling Spiral Drill Collar

Z02 

Sprial Grooving
Sprial grooving in order to avoid differential pressure sticking in the hole.

Spiral Grooved Drill Collars:Usual Sizes

Note 1-loss of weight is approximatively 4%, compared to slick drill collars.
Note 2-length of spiraled section allows reconditionning of connections.

Stress Relief Groove & Bore Back Box

• Stress relief grooves improve bending strength of pin and box connections and, therefore, durability. Stress relief grooves for box and pin are defined by API.
• Bore back box is nothing but gradual reduction of internal diameter by gradually increasing material cross sectional area at critical section. 
• This will ultimately reduce drastically stress concentration during static/dynamic loading and prevents box connections from failure.

Hardbanding

• We provide several hardbanding materials for customer's choice: Arnco-100XT, Arnco-300XT, TCS-800.

Slip and Elevator Recess

• Slip and elevator recesses improve downhole handing efficiency and safety. Slip and elevator recesses are machined in accordance with API 7-1.

Recommended Hardbanding Location

• -Drill collars with slip and elevator recesses(ZIP)
• 4" long wear pad above elevator recess
• 1" long wear pad above slip recess.
• 10" long wear pad under slip recess.
• -Drill collars with slip recess:
• 10" long wear pad under slip recess,
• 4"long wear pad above slip recess.
• -Drill collars without slip and elevator recesses:
• 10" long wear pad at 30" from pin shoulder.

Drill Collars

In our factory, we can produce special-use machine tools for oil-field, Including CNC or Non-CNC Oil Country Lathe(Pipe Thread Lathe), CNC or Non-CNC Deep Hole Boring and Drilling Machine, CNC Deep Hole Honing Machine, etc.

Oil Pipe Thread Lathe

Deep Hole Machine