φ50 Threaded Type Sonic Logging Pipe (50mm Screw-On CSL Pipe)

The φ50 (50mm OD) Threaded Type CSL Pipe is a premium, high-strength solution engineered for cross-hole sonic logging in deep foundation piles. This pipe utilizes precision-machined male and female threads with a heavy-duty rubber O-ring seal, ensuring a straight, rigid, and completely watertight joint. It is designed to withstand structural vibrations and axial loads during cage lowering, completely eliminating the need for on-site welding or hydraulic tools.

Key Features & Advantages

Self-Locking Thread Joint: Precision-engineered coarse threads provide a secure mechanical lock that resists high tensile forces and vibrations during reinforcement cage lowering.

High-Pressure Dual Sealing: Equipped with a high-durability rubber gasket in a specialized groove at the base of the thread, ensuring zero slurry penetration under deep subterranean hydrostatic pressures.

Fast Tool-Free Assembly: Connections can be easily engaged by hand and tightened with standard pipe wrenches directly on the platform, saving significant field labor costs.

Optimal Internal Verticality: Compared to socket or press-fit joints, the threaded coupling delivers superior structural alignment, keeping the 50mm testing channel straight for standard 25mm ultrasonic probes.

Technical Specifications

Our φ50 screw-on sonic logging tubes are manufactured from high-grade carbon steel to meet precise geotechnical standards:

Parameter	Specification Details
Outer Diameter (OD)	50 mm
Wall Thickness (WT)	1.0 mm to 3.5 mm
Material Grade	High-Grade Carbon Steel (ST37 / Q235 / Q345)
Thread Type	Specially engineered coarse thread for rapid field engagement
Standard Length	6 m, 9 m, 12 m (Customizable)
Surface Treatment	Bare (uncoated) / Anti-corrosion Oiled

Quality Assurance & Performance Testing

Each batch of φ50 Threaded CSL Pipes undergoes strict factory inspections before shipment:

Thread Compatibility Testing

Every production batch undergoes manual thread engagement tests to ensure that the male and female couplings screw together smoothly without cross-threading on-site.

High-Pressure Hydrostatic Leak Testing

Our threaded connections are verified under controlled pressure conditions to withstand the intense internal and external concrete pouring pressures found in deep boreholes.

Installation Instructions

Prep: Remove the protective plastic thread caps from both ends and inspect the threads and rubber seals.

Align: Position the upper φ50 pipe vertically and align the male and female threads.

Tighten: Hand-thread the joint tightly, then use a standard pipe wrench to apply final torque. This ensures the integrated rubber gasket is fully compressed for a watertight barrier.

Frequently Asked Questions (FAQ)

Q: What is a φ50 Threaded (Screw-on) sonic logging pipe, and when should I choose it over the press-fit type?

A: A φ50 Threaded sonic logging pipe utilizes high-precision male and female screw threads at the pipe ends, equipped with a heavy-duty rubber O-ring gasket. You should choose the threaded type for deep foundation piles (typically exceeding 30 to 50 meters) or heavy rebar cages. While press-fit types are great for speed in shallow-to-medium piles, threaded joints provide significantly higher tensile and torsional strength, ensuring the pipe string won’t break, cross-thread, or decouple when lowering heavy steel cages into deep boreholes.

Q: How do φ50 threaded joints guarantee zero slurry leakage under high hydrostatic pressure in deep piles?

A: Deep piling exposes the tube to intense subterranean water and concrete pressure. Our φ50 threaded sonic logging tubes feature an engineered tapered or straight thread coupling system with an integrated rubber sealing ring. As the male and female ends are screwed tightly together, the rubber ring is mechanically compressed inside a specialized groove, forming a gas-tight, liquid-tight barrier. It easily withstands deep hydraulic pressures, preventing any slurry from entering and blocking the ultrasonic testing channel.

Q: Do I need any special welding certification or heavy machinery to install φ50 threaded sonic tubes on-site?

A: Not at all. One of the primary advantages of our screw-on sonic tubes is 100% weld-free on-site installation. No expensive welding machines or certified welders are required. The pipes can be hand-threaded initially and then easily torqued to a secure lock using standard pipe wrenches (pipe tongs) directly on the rebar cage platform, saving substantial project time and cutting labor costs.

Q: What steel grades and dimensional specs are available for your φ50 threaded sonic logging tubes?

A: We supply premium cold-drawn carbon steel tubes complying with ASTM A53, EN 10219, and global non-destructive testing (NDT) guidelines. Standard Outer Diameter is 50mm, with wall thicknesses optimized from 1.5mm up to 3.5mm for heavy-duty deep-well resistance. Our precise dimensional tolerance ensures uniform wall thickness, preventing ultrasonic wave refraction and ensuring highly accurate Crosshole Sonic Logging (CSL) test results.

Q: Do the φ50 threaded sonic tubes come with bottom caps, top plugs, and necessary installation accessories?

A: Yes, we supply a fully integrated system. Each set can be ordered with pre-welded watertight steel bottom caps (to seal the base of the pipe string) and removable plastic or steel top plugs to prevent mud, concrete splashes, or debris from falling into the tube during the construction phase before testing begins.