In the demanding world of oil and gas exploration, where drilling operations push equipment to their limits, the S135 drilling pipe stands as a pinnacle of strength and reliability. Designed to withstand ultra-deep wells, high-torque environments, and corrosive conditions, S135-grade drill pipes are critical to operational success.
Precision Manufacturing Of S135 Drilling Pipes
Our S135 drilling pipes are crafted through a rigorous, multi-stage production process to ensure structural integrity and longevity:
Premium Material Selection
High-strength alloy steel (AISI 4145H or equivalent) is sourced to meet strict API 5DP chemical composition requirements (C: 0.28–0.33%, Cr: 0.8–1.2%, Mo: 0.15–0.25%).
Traceability is ensured from raw material batches, with certified mill test reports (MTRs) validating compliance.
Seamless Tube Formation
Rotary piercing and hot-rolling processes create seamless tubes with uniform wall thickness (±5% tolerance), eliminating weak points inherent in welded alternatives.
Quenching & Tempering (Q&T) Heat Treatment
Advanced induction hardening followed by controlled tempering achieves a minimum yield strength of 135,000 psi (930 MPa) and optimal toughness for shock load resistance.
Microstructure refinement ensures resistance to sulfide stress cracking (SSC) in H2S-rich environments.
High-Precision Thread Machining
CNC-controlled threading machines produce API-registered connections (e.g., NC50, FH), with thread pitch accuracy within ±0.025 mm.
Phosphate coating or copper plating is applied to enhance galling resistance and extend thread life.
Non-Destructive Testing (NDT)
100% ultrasonic testing (UT) and magnetic particle inspection (MPI) detect subsurface flaws, while hydrostatic testing at 1.5× working pressure guarantees leak-proof performance.
Heat Treatment: BK, BKS, BKW, GBK, NBK
Process: perforation/pickling/phosphating/cold drawn/cold rolling/annealing/anaerobic annealing
Protection: Anti-rust oil on inside and outside surface, plastic caps in both ends.
Packing: Bundle with steel strip and PE sheet or wooden case
