EN
Casing Cutter | Hydraulic Internal Pipe Cutter BQ NQ HQ PQ Wireline Core Drilling Fishing Tool
Casing Cutter is a special downhole accident handling auxiliary tool for wireline core drilling. As a DCDMA-standard hydraulic internal pipe cutter, it is manufactured in four sizes: BQ, NQ, HQ and PQ, compatible with all series of standard drill rods and casings.
Description
The pipe cutter is a special downhole accident handling auxiliary tool for wireline core drilling. As a DCDMA-standard hydraulic internal pipe cutter, it is manufactured in four sizes: BQ, NQ, HQ and PQ, compatible with all series of standard drill rods and casings.
When encountering stuck drilling, buried drill strings, burnt drill pipes or seized pipes that cannot be pulled out during construction, lower the pipe cutter into the faulty pipe. Driven by mud hydraulic pressure from the drilling rig, the carbide cutting inserts perform radial cutting to accurately sever drill rods or casings. Segmented fishing can then be carried out to prevent borehole abandonment and total loss of pipes. It is widely adopted in drilling projects including mineral exploration, deep geothermal well drilling and geotechnical investigation.
Working Principle
Connect the cutter with smaller guide drill rod and run to target cutting depth. Activate mud pump to push internal piston and expand two carbide cutting blades against pipe inner wall. Rotate drill string slowly for complete circumferential cutting. After pump shutdown and pressure relief, built-in spring retracts blades automatically for smooth tripping out of borehole.
Size Matching Specification
* BQ Pipe Cutter: The smallest size, for cutting shallow-hole BQ drill rods and thin-wall casings.
* NQ Pipe Cutter: Universal small-medium size, for general geological surveys and accident handling in medium & shallow boreholes.
* HQ Pipe Cutter: Mainstream medium-large size, standard salvage tool for medium-deep boreholes and shallow geothermal wells.
* PQ Pipe Cutter: Heavy-duty large size, suitable for 3000-meter ultra-deep boreholes and thick-wall PQ drill rods & casings.
Structural Composition
1. Top DCDMA Thread Connector: Fast connection with matching drill rod
2. Integral Forged Alloy Steel Body: Polished anti-rust surface, anti-extrusion & mud corrosion resistant
3. Hydraulic Piston Drive Assembly: Wear-resistant sealing for stable pressure transmission
4. Double Replaceable Tungsten Carbide Cutting Blades
5. Built-in Reset Spring: Auto retract blades to prevent pipe scratching
6. Bottom Guide Nose: Taper design for smooth entry into deformed stuck pipes
Core Advantages
1. One-piece forged steel body with anti-rust polishing, durable under ultra-deep high-pressure mud conditions.
2. Symmetrical dual carbide blades deliver smooth full-circle cut without metal debris falling into borehole.
3. Mud pump driven design, no extra hydraulic or explosive equipment required, easy field operation.
4. Automatic blade retraction spring avoids secondary borehole damage during tripping.
5. Modular replaceable cutting blades reduce long-term maintenance cost for drilling projects.
6. Non-explosive safe structure, compliant with mining site HSE construction regulations.
7. DCDMA standard dimension, universally interchangeable with all brands BQ/NQ/HQ/PQ drill pipes & casings.
