Engineered for rotary drilling & piling foundation projects — high-rigidity, collapse-resistant, custom-built for unstable strata.
Heavy Duty Double Wall Steel Borehole Casing Pipe is specially manufactured for rotary drilling and piling foundation projects. Its unique double-wall structure delivers exceptional rigidity and compressive strength — critical for maintaining borehole integrity in loose, gravelly, or highly unstable strata where conventional casings risk collapse.
Made from high-tensile structural steel with precise wall thickness control, the casing resists bending under lateral earth pressure and dynamic drilling loads. It serves dual functions: protecting the borehole wall during drilling *and* acting as permanent structural reinforcement during concrete placement — eliminating the need for temporary withdrawal and reducing construction time and risk.
Double-wall geometry increases moment of inertia by up to 3.2× vs. single-wall pipe — proven effective in sandy, gravel, and water-bearing formations where hole sloughing is common.
Designed for direct embedment into reinforced concrete piles — no retrieval required. Seamlessly transitions from temporary support to permanent load-bearing element.
Full dimensional customization: OD from 325mm to 1200mm, wall thickness 12–32mm, lengths up to 18m. Optional flange connections, internal coatings, and ultrasonic testing certification.
High-rise basements, metro stations, bridge abutments in densely built areas with limited access and strict vibration control.
Riverbank stabilization, port infrastructure, and coastal reclamation on alluvial silt, clay, or quicksand layers.
Casing advancement through fractured bedrock or boulder zones using oscillator-assisted installation.
| Parameter | Standard Range | Notes |
|---|---|---|
| Outer Diameter (OD) | 325 mm – 1200 mm | Tolerances per ISO 11960 |
| Wall Thickness (per layer) | 12 mm – 32 mm | Total wall = 2 × nominal thickness |
| Length | 6 m – 18 m (standard 12 m) | Cut-to-length available |
| Material Grade | Q345B / S355JO / ASTM A106 Gr.B | Certified mill test reports provided |
| Connection Type | Welded butt joint / Threaded API 5CT | Flanged options for rapid assembly |
| Surface Treatment | Black painted / Zinc-coated (optional) | For corrosion resistance in saline environments |
A: Seamless or welded outer and inner tubes are concentrically assembled and longitudinally welded at both ends — creating a rigid annular cavity that enhances buckling resistance without adding excessive weight.
A: Yes — specifically designed for compatibility with full-casing oscillators and hydraulic drive systems. Standard thread pitch and torque ratings align with major OEM equipment interfaces.
A: Mill Test Report (MTR), Dimensional Inspection Report, Welding Procedure Qualification Record (WPQR), and Video outgoing-inspection report — all provided digitally and upon request in hard copy.
A: Yes — we offer OEM engineering support including finite element analysis (FEA) validation, custom flange design, internal epoxy lining (NSF/ANSI 61 certified), and laser-etched traceability marking.
Share your borehole depth, soil profile, and equipment specs — we’ll deliver a tailored casing solution with technical drawings and lead time within 48 hours.
Contact Our Engineering TeamZZST • Hunan, China | ISO 9001 Certified Manufacturer Since 2008
