NQ3 HQ3 PQ3 Split Tube Core Barrel Half-Open Inner Tube

The rope core semi-union pipe is also known as the open-close type core semi-union pipe or the split-type inner pipe. It belongs to the core accessory of the geological drilling rope core assembly, and is suitable for the BQ/NQ/HQ/HRQ/PQ series of rope core drill pipes. It can be used in combination with the inner pipe assembly, locking pins, fishing spear, plug head and other accessories. 

The rope core semi-union pipe is also known as the open-close type core semi-union pipe or the split-type inner tube. It belongs to the core accessory of the total assembly of rope core core retrieval tools in geological drilling. It is compatible with the entire series of rope core drill pipes such as BQ/NQ/HQ/HRQ/PQ, and can be used in combination with the inner tube assembly, locking clips, retrieval spear, plug, etc., as a complete set of equipment.
The product adopts a longitudinal semi-open and integrated structure. It differs from the traditional seamless inner tube as a whole. It is specially developed for fractured strata, loose rock layers, weathered rock layers, and weak mineral layers. It is a necessary core retrieval accessory for mine exploration, deep geological drilling, geotechnical engineering investigation, and scientific deep drilling, perfectly adapting to the deep hole and high-load drilling conditions of HRQ double-ended quenched rope core drill pipes.
Overall structure: Two symmetrical semi-circular tube bodies + positioning locking clips + upper and lower connection joints. The opening and closing are smooth, the alignment is precise, the assembly and disassembly have no jamming, the coaxiality is high, and there is no jamming or uneven wear after being lowered into the drill pipe.
Material selection: High-strength alloy seamless steel pipe is used, with overall quenching and heat treatment, ensuring balanced hardness; the pipe wall is uniformly thickened, resistant to compression and deformation, suitable for deep hole high-pressure mud, and complex stratum construction.
Standard specifications: Compatible with industry standards BQ, NQ, HQ, HRQ, PQ of all models; the regular length is 1.5m and 3m, and non-standard customization is supported. Seamless and compatible with the regular inner tube and HRQ high-strength drill pipe complete system.

1.The integrity of the core samples is at its highest level, and the core extraction rate has significantly increased.
The open-and-closed modular design allows for the core samples to be directly separated and half-closed after extraction, without the need for hammering, squeezing, or water flushing of the core samples. This completely avoids problems such as broken core samples, soft soil layers, and loose collapse of weathered rock layers. The rate of core samples for complex strata can reach over 98%, preserving the original structure, bedding, and vein structure of the rock layers. The geological sampling data is precise.
2. It is compatible with HRQ deep-hole drill pipes， with strong adaptability for deep-hole working conditions.
The pipe body has strong toughness， resistance to confining pressure， and resistance to crushing damage. It is suitable for HRQ end quenched high-strength drill pipes with a length of 2000-2500 meters for ultra-deep hole， inclined hole， and high-torque drilling construction. It can resist compression and not deform in the hole， fitting well with deep-hole high-pressure and complex stress construction environments， and suitable for heavy-load drilling operations in deep wells.
3. Wear-resistant and durable， with a longer service life.
Overall quenching treatment is carried out， making the pipe wall wear-resistant， resistant to mud corrosion， and resistant to frictional loss of rock layers. The joint positioning is precise， and during the insertion and extraction process， it does not scrape the inner wall of the drill pipe， does not wear the HRQ or HQ rope core extraction drill pipe， reducing the wear of the entire drilling tool and the frequency of accessory replacement.
4. Efficient disassembly and assembly， significantly saving construction time.
It comes with a positioning lock， which locks firmly after closing. It does not crack by itself during drilling. On the ground， the sample can be quickly opened and closed without professional tools. The core extraction speed is much faster than that of ordinary overall inner tubes， shortening the auxiliary period for raising the drill pipe and extracting the core， and improving the overall drilling construction efficiency.
5. Strong versatility， with high compatibility of the entire set.
Standard national dimensions are used， which can be matched with all brands of rope core extraction inner tubes， snap rings， sand tubes， HRQ high-strength drill pipes， and thin-walled rope core extraction drill pipes. No need for modification， direct replacement is possible， and the compatibility of accessories is maximized.
6. Anti-clogging and low loss.
The pipe body has high straightness and a smooth outer wall. Combined with the large-diameter structure of thin-walled/HRQ rope core extraction drill pipes， the resistance during lowering and recovery in the hole is small， avoiding deep-hole clogging， pump blockage， and inner tube jamming faults， and reducing the rate of downhole drilling accidents.

* Crushed rock strata, rock strata with joint development, loose sand strata, strongly weathered and weak strata
* Deep exploration in metal and non-metal mines, core sampling operations in multi-crushed ore layers
* Ultra-deep holes ranging from 1500 to 2500 meters, inclined holes, cluster holes (suitable for HRQ quenched and tempered drill pipes)
* Geotechnical investigations for highways, railways, and water conservancy projects, geothermal drilling, geological scientific drilling projects