Product Overview
The Coiled Tubing Weight Bar, also known as Downhole Sinker Bar, is an essential passive weighted accessory designed for full-series coiled tubing well intervention operations. It is conventionally installed at the upper section of downhole tool strings, including hydraulic setting tools, bridge plug assemblies, jetting tools and other coiled tubing downhole equipment.
The core working principle of the weight bar is to increase the overall dead weight of the entire tool string. It effectively overcomes the inherent flexibility of continuous coiled tubing, reduces wellbore wall friction and buoyancy in horizontal, highly deviated and deep vertical wells, and provides stable downward running force to ensure smooth and accurate tool string delivery to the target downhole depth. This solves the common industry problem of insufficient downward pushing force, tool suspension and shallow running depth during coiled tubing intervention.
This weight bar adopts a solid one-piece integral forging structure with high mechanical rigidity, effectively avoiding bending, deformation and structural failure under downhole tensile and compressive loads. The product lineup covers complete outer diameter specifications from 1-1/2" to 3-1/2", supporting two independent working condition material grades: STD standard carbon steel for conventional low-corrosion well environments, and H₂S sour service anti-sulfide stress corrosion alloy fully compliant with NACE MR0175 standards for high-hydrogen-sulfide corrosive oil and gas wells.
All models are equipped with industry-standard connection threads, including 1" AMMT, 1-1/2" AMMT, 2-3/8" PAC and NC26 threads, realizing seamless matching with mainstream coiled tubing tool strings and downhole service tools. With standardized overall length and unified structural design, the weight bar features simple on-site assembly, zero complex internal moving parts and ultra-low daily maintenance requirements, becoming a universal standard accessory for global oilfield coiled tubing well intervention projects.
Complete Technical Specification Table
| PN Part Number | Outer Diameter OD | Internal Through Bore ID | Overall Make-Up Length | Working Condition Grade | Connection Thread |
|---|---|---|---|---|---|
| L4011500120 | 1-1/2" | 0.5" | 37.5" | STD Standard Carbon Steel | 1" AMMT |
| L4011690120 | 1-11/16" | 0.55" | 37.5" | STD Standard Carbon Steel | 1" AMMT |
| L4011750120 | 1-3/4" | 0.55" | 37.5" | STD Standard Carbon Steel | 1" AMMT |
| L4012125120 | 2-1/8" | 0.7" | 38" | STD Standard Carbon Steel | 1-1/2" AMMT |
| L4012250120 | 2-1/4" | 0.7" | 38" | STD Standard Carbon Steel | 1-1/2" AMMT |
| L4012500120 | 2-1/2" | 0.78" | 38" | STD Standard Carbon Steel | 1-1/2" AMMT |
| L4012875120 | 2-7/8" | 0.78" | 38" | STD Standard Carbon Steel | 2-3/8" PAC |
| L4013500120 | 3-1/2" | 1.5" | 38" | STD Standard Carbon Steel | NC26 |
| L4011500320 | 1-1/2" | 0.5" | 37.5" | H₂S Sour Service Anti-Sulfide Corrosion Alloy | 1" AMMT |
| L4011690320 | 1-11/16" | 0.55" | 37.5" | H₂S Sour Service Anti-Sulfide Corrosion Alloy | 1" AMMT |
| L4011750320 | 1-3/4" | 0.55" | 37.5" | H₂S Sour Service Anti-Sulfide Corrosion Alloy | 1" AMMT |
| L4012125320 | 2-1/8" | 0.7" | 38" | H₂S Sour Service Anti-Sulfide Corrosion Alloy | 1-1/2" AMMT |
| L4012250320 | 2-1/4" | 0.7" | 38" | H₂S Sour Service Anti-Sulfide Corrosion Alloy | 1-1/2" AMMT |
| L4012500320 | 2-1/2" | 0.78" | 38" | H₂S Sour Service Anti-Sulfide Corrosion Alloy | 1-1/2" AMMT |
| L4012875320 | 2-7/8" | 0.78" | 38" | H₂S Sour Service Anti-Sulfide Corrosion Alloy | 2-3/8" PAC |
| L4013500320 | 3-1/2" | 1.5" | 38" | H₂S Sour Service Anti-Sulfide Corrosion Alloy | NC26 |
Note: Custom outer diameter size, internal bore size, overall length and special thread specifications are available upon engineering consultation. All standard models support STD conventional and H₂S sour service dual working conditions, fully matching global mainstream coiled tubing tool string assembly standards.
Core Features & Advantages
Solid One-Piece Integral Forging Structure, High Structural Rigidity
Adopts one-piece solid forging molding process without segmented splicing or welding structure. The overall mechanical strength and structural stability are excellent, effectively resisting downhole tension, compression and torsion loads. It avoids bending, distortion and structural damage during long-distance tripping in high-friction wellbores, ensuring long-term stable downhole service performance.
Dual Grade Material Design for Full Well Condition Coverage
Provides two independent material versions to adapt to different downhole fluid environments. The STD standard carbon steel version is cost-effective and suitable for conventional low-sulfur, low-corrosion onshore and offshore oil and gas wells. The H₂S sour service alloy version complies with NACE MR0175 international anti-sulfur standards, effectively preventing sulfide stress cracking (SSC) and corrosion failure, perfectly adapting to high-H₂S sour gas wells and acidizing corrosive working conditions.
Full-Size Standard Thread Matching System
Fully configured with oilfield mainstream standard threads: small OD models match 1" AMMT threads, medium OD models adopt 1-1/2" AMMT threads, large-size models support 2-3/8" PAC and NC26 drill pipe threads. All thread specifications are strictly standardized, realizing direct plug-and-play assembly with coiled tubing strings, hydraulic setting tools and bridge plug tool strings without secondary modification or adapter conversion.
Excellent Downhole Auxiliary Running Performance
Increases total tool string weight significantly to offset coiled tubing flexibility and wellbore buoyancy. It solves the technical difficulties of difficult running, tool hovering and insufficient penetration in horizontal wells, large-angle deviated wells and deep vertical wells, greatly improving the success rate and construction efficiency of coiled tubing intervention operations.
Complete Standard Size Series, Wide Compatibility
Covers full outer diameter specifications from 1-1/2" to 3-1/2", with unified standardized length design for small and large sizes. The complete product portfolio can match slim coiled tubing strings, conventional tool strings and heavy-duty large-size downhole tool assemblies, realizing full-scene coverage of coiled tubing well intervention operations.
Ultra-Low Maintenance & Simplified On-Site Operation
No internal moving parts, no spring components or sealing vulnerable parts. The whole structure is simple and durable. On-site installation only requires standard threaded connection, which greatly shortens tool string assembly time. After well service, only regular surface cleaning and appearance inspection are needed, reducing after-sales maintenance costs and spare parts inventory pressure.
Application Scenarios
1. Conventional oil and gas well coiled tubing intervention operations, including bridge plug setting, sand jet perforation, wellbore cleaning and reservoir stimulation construction.
2. Horizontal wells and high-angle deviated well intervention projects, solving tool string floating, friction resistance and difficult running problems.
3. Deep vertical well coiled tubing construction, providing stable downward weight assistance to ensure tool string reaching target reservoir depth.
4. High-sulfur sour oil and gas well intervention operations, adopting NACE-compliant H₂S anti-corrosion grade to adapt to severe corrosive downhole fluid environments.
5. Onshore and offshore oilfield routine well maintenance, well plugging, abandonment and secondary reservoir reconstruction intervention operations.
6. Supporting tool string assembly with hydraulic setting tools, indexing tools and jetting subs to form a complete standardized coiled tubing service tool combination.
Standard Delivery Package
Complete pre-assembled integral weight bar unit with standard factory thread finishing and surface anti-rust treatment.
Professional thread protective buckle and anti-collision packaging accessories for transportation and storage protection.
Factory dimension inspection report, material chemical composition and mechanical property test certificate.
Official product installation guidance and tool string matching operation manual.
Optional customized thread inspection report and third-party material certification for overseas project bidding requirements.
Quality Warranty & After-Sales Service
Warranty Coverage: 12 months after factory shipment or 500 times cumulative downhole tripping cycles, whichever comes first.
Full factory inspection: All weight bars pass dimensional tolerance detection, thread precision inspection, tensile strength test and surface defect detection before delivery.
Free technical support: Professional tool string matching consultation, size selection guidance and working condition grade recommendation for global clients.
Long-term spare parts supply: Complete size series inventory supports bulk wholesale and fast global delivery.
Custom service: Support non-standard outer diameter, length, thread type and special anti-corrosion material customization according to client drawings and well conditions.
FAQ
Q1: What is the main function of a coiled tubing weight bar?
A1: The weight bar is a core weighted auxiliary tool for coiled tubing well intervention. It is installed on the upper tool string to increase overall assembly weight, effectively overcome coiled tubing flexibility, wellbore friction and downhole buoyancy. It ensures smooth downward running of tools in horizontal, deviated and deep wells, supporting bridge plug setting, perforation and wellbore cleaning operations.
Q2: What is the difference between STD and H₂S sour service weight bar?
A2: The STD grade adopts standard carbon steel, cost-effective for conventional low-sulfur, low-corrosion oil and gas wells. The H₂S sour service version adopts NACE MR0175 certified anti-sulfide alloy material, resisting sulfide stress cracking and fluid corrosion, specially designed for high-sulfur sour gas wells and acidized corrosive downhole environments.
Q3: What thread types are available for this weight bar?
A3: Our full-series weight bars are equipped with industry-standard threads including 1" AMMT, 1-1/2" AMMT, 2-3/8" PAC and NC26 threads. Different outer diameter models correspond to fixed standard threads, realizing direct matching with hydraulic setting tools, coiled tubing strings and other downhole intervention tools without adapters.
Q4: Why use solid one-piece weight bar for coiled tubing intervention?
A4: The integral solid forging structure eliminates welding seams and structural weak points. It provides higher rigidity and tensile strength during long-distance tripping, effectively prevents bending and deformation under high wellbore friction, ensuring stable tool string running accuracy and high construction success rate.
Q5: Do you support customized weight bar specifications?
A5: Yes. We provide custom outer diameter, inner bore size, overall length, special thread and special anti-corrosion material solutions. All custom products can be manufactured according to client technical drawings and actual downhole working conditions.
Get Custom Datasheet & Factory Quote
We are a professional OEM & ODM manufacturer focused on full series oilfield coiled tubing well intervention tools, providing high-reliability downhole weight bars, hydraulic setting tools, bridge plugs and supporting downhole service tools for global oil and gas fields. All products adopt standardized forging process and strict factory testing, stable performance and high cost performance. Whether you need standard-size STD/H₂S grade weight bars or non-standard customized specifications, please feel free to contact our engineering team. We will provide professional tool string matching solutions, detailed technical datasheets and competitive factory wholesale quotations within 24 hours.
