The Mechanical Casing Collar Locator is a dedicated mechanical downhole tool designed for oilfield wireline logging and cased-hole intervention work. Its core function is to accurately identify casing collar positions inside wellbores, supporting precise depth calibration for the full downhole tool string. This calibration effectively eliminates depth measurement deviations generated by wireline cable stretch and surface counting errors during logging and perforation construction.
This product adopts a pure mechanical contact detection structure, without radioactive isotopes, circuit boards or electronic sensors, which brings high operation safety and completely avoids radioactive pollution risks. All standard models are manufactured with STD standard carbon steel, compatible with four mainstream casing outer diameters including 4", 4-1/2", 5" and 5-1/2". Each specification is pre-machined with standard PAC and UPTBG premium tubing connection threads, enabling direct assembly with wireline logging tools and perforating gun strings without extra transition subs. Customized non-standard sizes, special connection threads and anti-corrosion alloy materials are available upon technical consultation.
All standard products adopt STD working condition carbon steel material, with four independent PN model numbers for different casing sizes:
PN L4054000120: Matches 4" casing OD, tool OD 2-7/8", tool inner bore 0.8", make-up length 15.9", connection thread 2-3/8" PAC
PN L4054500120: Matches 4-1/2" casing OD, tool OD 3-1/4", tool inner bore 0.98", make-up length 15.9", connection thread 2-3/8" UPTBG
PN L4055000120: Matches 5" casing OD, tool OD 3-5/8", tool inner bore 1.18", make-up length 17.5", connection thread 2-3/8" UPTBG
PN L4055500120: Matches 5-1/2" casing OD, tool OD 4-1/16", tool inner bore 1.57", make-up length 17.5", connection thread 2-7/8" UPTBG
Customized non-standard outer diameter, inner flow bore, assembly length and special connection threads are supported via engineering consultation. Besides standard STD carbon steel, anti-corrosion alloy customized versions can be provided for high-H₂S corrosive downhole environments. This locator can be combined with gamma logging tools and perforating guns to form integrated logging-perforation tool strings.
Wear-Resistant Reinforced Locator Keys:The contact locating keys adopt professional wear-resistant strengthening treatment. The enhanced surface hardness greatly reduces metal abrasion loss during repeated up-and-down tripping inside casing, avoids casing collar detection failure caused by excessive key wear, extends the overall service cycle of the tool and cuts the frequency of spare key replacement for field construction teams.
Adjustable Surface Weight Indicator:The matched surface weight signal display device supports adjustable sensitivity. Field engineers can adjust trigger thresholds according to actual wellbore fluid and casing wall conditions. When the tool passes through casing collars, obvious weight jump signals will appear on the surface gauge, allowing construction staff to record accurate depth benchmark data conveniently.
Pure Mechanical Non-Radioactive Structure:This locator relies entirely on mechanical contact trigger signals, without integrated radioactive sources or electronic components. It eliminates strict radioactive material management requirements, and will not suffer complete signal failure or circuit burnout under high downhole temperature environments, delivering stable performance in various cased hole operation conditions.
Complete Standard Size Matching Scheme:The full product line covers four widely used casing outer diameters in global oilfields: 4", 4-1/2", 5" and 5-1/2". Every size matches exclusive tool outer diameter, inner flow bore and fixed make-up length to fit different casing inner wall dimensions perfectly.
Standard Premium Tubing Connection Threads:Each specification is pre-processed with three industry-standard premium threads: 2-3/8" PAC, 2-3/8" UPTBG and 2-7/8" UPTBG. All thread manufacturing complies with international oilfield precision machining standards, enabling seamless matching with mainstream wireline logging assemblies, perforating gun strings and wireline bottom-hole intervention tools worldwide.
Simple On-Site Assembly & Low Maintenance Cost:The integrated split internal structure contains few vulnerable spare parts. Field engineers can complete tool disassembly, locating key replacement and surface indicator sensitivity adjustment without special maintenance equipment, greatly reducing daily maintenance labor and cost for oilfield service companies.
1. Wireline cased-hole logging and reservoir perforation depth calibration. As the core supporting tool for formation evaluation logging and perforation construction, it marks casing collar depth benchmarks to ensure logging instruments and perforating guns are accurately positioned at target reservoir intervals.
2. Wireline downhole intervention depth verification. Widely applied in bridge plug setting & retrieval, casing cleaning, acidizing and reservoir stimulation operations, it calibrates true running depth of downhole working tools to prevent construction failures caused by depth positioning deviation.
3. Casing inspection and well integrity diagnosis. Matched with casing caliper and inspection camera, it provides continuous depth reference data for casing inner wall defect inspection, marking corrosion, deformation and leakage points with precise depth values.
4. Conventional low-corrosion onshore oil and gas well service. All STD carbon steel models adapt to standard downhole environments with low hydrogen sulfide and moderate temperature & pressure, covering vertical, deviated and horizontal well wireline logging projects for land oilfields.
Fully pre-assembled mechanical casing collar locator main unit with anti-rust passivation treatment on connection threads
Spare wear-resistant locating key sets, internal elastic spring accessories and plastic thread protective caps for transportation and storage
Complete factory inspection documents, including dimensional tolerance test report, raw material composition certification, locating key wear resistance test record and mechanical trigger signal calibration report
Multi-language product installation and operation manual, including tool disassembly steps, surface weight indicator sensitivity adjustment guidance and standard well tripping operation procedures for field engineers
Optional third-party material certification documents and wireline tool string matching scheme files to meet overseas oilfield project bidding supporting material requirements
Warranty Scope: 12 full months after factory shipment or 500 cumulative downhole tripping & detection cycles, whichever condition is reached first
Strict Full-Process Factory Inspection: Every finished locator passes multiple rigorous tests before delivery, including dimensional detection, thread precision inspection, locating key expansion force test, surface weight signal trigger calibration and full surface visual defect inspection, ensuring stable performance across all batches
Free Global Professional Oilfield Technical Support: Provide free casing size matching consultation, integrated wireline tool string assembly scheme design and surface weight indicator parameter adjustment technical guidance for domestic and overseas oilfield service clients
Long-Term Stable Spare Parts Global Supply Chain: Full size series of mechanical casing collar locators are kept in factory finished goods inventory to support bulk wholesale orders. Flexible global sea and air freight delivery schedules can be arranged according to client oilfield project construction timelines
Customized Professional Engineering Solution Service: Support development and production of non-standard size mechanical casing collar locators and high anti-corrosion alloy material customized versions strictly in accordance with client technical drawings, field well downhole working condition parameters and special customized wireline construction operation requirements
Q1: What is the difference between mechanical casing collar locator and radioactive electronic casing collar locator?
The mechanical casing collar locator adopts pure mechanical contact detection structure without radioactive gamma source materials and electronic circuit components, with zero radioactive pollution risks. It will not be affected by high downhole temperature and features longer service life and lower daily maintenance costs. In contrast, radioactive electronic casing collar locators rely on radioactive isotopes and electronic sensors, which face strict radioactive material management requirements and are prone to complete signal failure and circuit burnout under high-temperature wellbore environments.
Q2: How does the adjustable surface weight indicator realize accurate well tool string depth calibration?
When the wear-resistant locating keys pass through casing collars, sudden inner diameter change of casing tubing generates obvious mechanical resistance force. This resistance signal is transmitted to the surface weight display gauge through the wireline logging cable. The adjustable surface indicator allows field engineers to modify the sensitivity of weight fluctuation signal feedback to match specific wellbore fluid and casing wall conditions. After adjusting to the optimal trigger threshold, the surface weight gauge will produce a distinct jump signal every time the tool passes a casing collar. Construction engineers record the depth numerical value corresponding to each weight jump signal, completing full depth calibration for the entire downhole wireline tool string.
Q3: What casing sizes and connection threads do standard mechanical casing collar locators cover?
Our full-series standard mechanical casing collar locator product line covers four mainstream casing outer diameter specifications widely used in global oilfields: 4", 4-1/2", 5" and 5-1/2". The supported premium tubing connection thread specifications include three industry standard variants: 2-3/8" PAC, 2-3/8" UPTBG and 2-7/8" UPTBG. All thread manufacturing specifications comply with unified international oilfield precision machining standards, enabling direct seamless matching with mainstream wireline logging tools, reservoir perforating gun tool strings and wireline bottom-hole intervention assemblies deployed across global oilfields without extra transition adapter subs.
Q4: What benefits does wear-resistant surface treatment bring to the locator keys?
The locating keys are core functional components that continuously slide and maintain contact with the inner wall of casing tubing during repeated downhole tripping operation cycles. Special professional wear-resistant surface strengthening treatment greatly improves the surface hardness and friction resistance of the key contact surfaces. During frequent up-and-down running cycles inside casing tubing, the treatment effectively reduces metal abrasion loss of locating key contact surfaces, avoids casing collar detection failure caused by excessive key wear, extends the overall service cycle of the full mechanical casing collar locator tool, and reduces the frequency of spare locating key replacement work for oilfield service construction teams.
Q5: Can customized non-standard specifications and anti-sulfide corrosion alloy versions be produced for harsh sour well environments?
Yes, we provide complete customized professional engineering solution services for all global oilfield service clients. We can manufacture mechanical casing collar locators with non-standard casing matching outer diameter sizes, special customized internal through bore diameters, modified overall assembly lengths and special non-standard connection thread specifications strictly in accordance with client technical drawing documents and field well downhole working condition parameters. Besides the standard STD carbon steel base material grade, high anti-corrosion alloy material versions fully compliant with sour service standards can be customized to adapt to harsh high-hydrogen-sulfide, high-chloride corrosive downhole well environments.
We are a professional integrated OEM & ODM manufacturer focusing on R&D, production and sales of full-series oilfield wireline & coiled tubing downhole intervention tools. We supply high-performance mechanical casing collar locators, flexible knuckle joints, torque subs, casing running tools, solid weight bars, perforating auxiliary accessories and a full range of matched supporting wireline downhole service tools for global onshore oil & gas field wireline logging, reservoir perforation and small-scale stimulation intervention construction projects. All our oilfield products adopt standardized metal forging and precision CNC machining production processes, and pass multiple rounds of rigorous factory performance testing including mechanical wear resistance, trigger signal stability and connection thread tensile load testing, featuring stable long-term downhole working performance and excellent comprehensive cost performance ratio. Whether you require standard-size STD carbon steel mechanical casing collar locators matched with conventional mainstream casing sizes, integrated wireline logging-perforation combined tool string matching design solutions, or customized high anti-corrosion alloy material versions with non-standard specifications for harsh sour corrosive well downhole environments, please feel free to contact our professional oilfield engineering technical team. We will provide targeted professional casing depth calibration downhole tool matching solutions, complete detailed technical datasheets and competitive factory bulk wholesale quotations within 24 working hours.
