Bucking units (joining units) are essential equipment used in the oil and gas industry to connect and disconnect drill pipe, tubing, casing, and other tools. They operate frequently, under heavy loads, and often operate in complex and changing field environments. To ensure continued efficient operation and connection accuracy, systematic and periodic maintenance is essential. Bucking unit maintenance involves multiple aspects, including the hydraulic system, electronic control system, mechanical structure, safety devices, and sensor systems. Systematic and standardized maintenance directly impacts equipment lifespan, operational efficiency, and safety.The following is a detailed description of the main maintenance items for a bucking unit:1. Hydraulic System MaintenanceThe hydraulic system is the core component of the bucking unit for power output and control operations. Any failure or contamination can lead to unstable operation or complete failure. Therefore, hydraulic system maintenance is one of the most critical aspects.1. Hydraulic Oil Replacement and MonitoringHydraulic oil is the system's working medium. Over time, it can deteriorate due to factors such as temperature fluctuations, contamination, and moisture ingress, affecting system response speed and accuracy. Regularly inspect the oil quality and replace it promptly if discoloration, foaming, or abnormal viscosity are observed. 2. Hydraulic Oil Level CheckThe oil tank level must remain within the normal range. If the oil level drops, locate the leak, refill the oil, and remove any air.3. Clean or Replace the Oil FilterThe filter is a key component that prevents particulate matter from entering the system. It should be replaced at the prescribed interval to prevent blockage, abnormal system pressure, or component damage.4. Check Hydraulic Lines and ConnectorsHydraulic hoses and connectors are susceptible to aging or loosening due to prolonged exposure to high pressure. Regularly check for leaks, damage, or loose connections to ensure proper system sealing.5. Hydraulic Cylinder and Valve Manifold MaintenanceInspect the hydraulic cylinder for unusual noises, sluggish movement, or internal leakage. Check the valve manifold for proper operation and any signs of sticking or poor response. Clean or replace seals if necessary.2. Electronic Control System MaintenanceThe electronic control system is responsible for drive control, signal acquisition, torque and angle management, and is the core of intelligent operation. Its stability directly impacts operational safety and connection quality. 1. Control Cabinet Interior CleaningRegularly inspect the control cabinet for dust accumulation, loose connectors, and damaged cables. Dust can cause short circuits or overheating, shortening system life.2. Cable and Connector InspectionVerify that cables are not broken or peeling, and that connectors are in good contact. Be careful to prevent poor contact caused by vibration or oil.3. Control Panel and Touchscreen TestingTest button responsiveness and touch accuracy. If there are operational delays or a black screen, check the control board power supply and display driver.4. PLC and Program System TestingPeriodically verify the functionality of the programmable logic controller, checking signal input and output for normal operation and any unexpected breakpoints in the program.5. Torque and Angle Control System CalibrationCalibrate the torque sensor and angle encoder to ensure accurate data acquisition and avoid overtightening or loosening connections.3. Mechanical Structure MaintenanceThe Bucking Unit consists of a base, mainframe, jaw system, and rotation mechanism. The stability of these mechanical components determines overall rigidity and operational accuracy. 1. Jaw System InspectionThe jaws are the core components that directly contact and clamp the workpiece. Check the jaw pads for wear, cracks, gaps, or deformation, and replace if necessary.2. Guide Rail and Slide LubricationAll sliding components, such as guide rails and slides, must be well lubricated. Dryness can lead to sluggish movement or abnormal noise, increased wear, and even seizure.3. Spindle and Coupling InspectionThe spindle system should be inspected for smooth operation and any eccentricity, runout, or abnormal vibration. The coupling should be inspected for tightness of the connecting bolts.4. Resetting Fasteners and ConnectorsPeriodically inspect all bolts, nuts, and pins for looseness, especially critical parts subject to alternating loads. These should be re-tightened regularly.4. Safety Device MaintenanceThe Bucking Unit operates under high torque and pressure, and any minor malfunction could potentially lead to a safety incident. The integrity of safety devices is the last line of defense for protecting equipment and personnel. 1. Emergency Stop Button TestPeriodically press the emergency stop button to test the response speed and immediate system shutdown to prevent failure at critical moments.2. Limit and Travel Protection CheckCheck that all limit switches and sensors are functioning properly to ensure that the clamping/unclamping action does not exceed the travel limit.3. Over-Torque Protection Function VerificationSet appropriate torque alarm and power-off points, and regularly test that the protective devices operate accurately when the torque exceeds the limit.4. Guard and Protective Structure InspectionCheck that the guard is intact and securely installed to ensure that the operator cannot easily access hazardous areas.5. Software System and Record MaintenanceModern bucking units are typically equipped with an operation record system and equipment self-diagnostic programs to support ongoing management and troubleshooting.1. Operation Data BackupRegularly export and save connected operation history data, alarm logs, and equipment parameters to prevent data loss.2. System Software UpdateUpgrade the software version as recommended by the equipment manufacturer to ensure system stability and compatibility. 3. Fault Self-Diagnosis Function TestTest the system's ability to automatically identify common faults and generate alarms, improving maintenance response speed.ConclusionBucking unit maintenance should not be limited to fault repair; it should also prioritize preventive and systematic management. The above maintenance items should be incorporated into the company's equipment management system, organized and implemented on a regular basis, with a comprehensive maintenance record and accountability system. Strictly adhering to the maintenance plan not only extends equipment life and improves operational efficiency, but also effectively prevents safety incidents and ensures the stability and reliability of the overall operating system. In high-intensity operating environments, standardized maintenance management is not only a technical requirement but also a cost-control and safety measure.

Bucking units are critical equipment in drilling operations, and their parts inevitably wear out under long-term, high-load, and high-frequency operating conditions. Part wear not only affects the proper operation of the equipment but can also degrade connection quality and even cause safety incidents. Therefore, scientific and rational replacement of worn parts is crucial to maintaining the performance and operational safety of the bucking unit. The following details the replacement procedures and precautions for worn bucking unit parts.1. Identification and Determination of Worn PartsBefore replacement, it is important to accurately identify and determine which parts are worn and require replacement. Common worn parts include jaw gaskets, hydraulic cylinder seals, oil seals, bearings, guide rails, and fasteners.Visual Inspection: Observe the surface of the parts for obvious scratches, cracks, deformation, or defects.Functional Testing: Problems such as sluggish operation, weakened clamping force, and hydraulic leakage during operation often indicate severe wear of the relevant parts.Dimensional Measurement: Measure the dimensions of key parts using specialized tools to determine whether they exceed the wear limits specified by the manufacturer or industry. Lubrication: Check the lubricating oil for metal shavings or unusual contaminants. If present, this may indicate increased wear on internal parts.After identifying worn parts, a replacement plan should be developed promptly to prevent further damage.2. Preparatory Work Before ReplacementShutdown and Power OffEnsure the Bucking Unit is completely stopped. Disconnect the hydraulic system power and electrical control power to prevent accidental startup.Clean the Work EnvironmentRemove oil and dust from the equipment surface. Keep the work environment clean and tidy to facilitate observation and subsequent operations.Tool and Spare PartsPrepare required specialized disassembly and assembly tools, screwdrivers, wrenches, etc., and ensure that replacement parts are from legitimate sources and of the correct model.Technical Data ReviewRefer to the equipment manual or service manual for disassembly and assembly procedures, precautions, and torque specifications.3. Disassembly Procedures for Wear PartsDepressurization and Oil DrainingBefore replacing hydraulic system parts, release system pressure to prevent hydraulic fluid from spraying out and injuring personnel. Drain the hydraulic fluid completely if necessary to prevent environmental contamination.Removing External AccessoriesFirst, remove external connectors associated with the worn parts, such as pipe joints, mounting bolts, and protective covers. Disassembling Main PartsAccording to the maintenance manual, use specialized tools to remove worn parts. Handle with care to avoid secondary damage to surrounding parts.Inspecting Removed PartsPerform a detailed inspection of the removed parts to determine the wear condition and cause, which will guide subsequent repair or replacement.4. Installation Procedure for New PartsCleaning the Installation AreaBefore installation, thoroughly clean the part mounting seat and related mating surfaces to ensure they are free of oil, impurities, and rust.Inspecting the Condition of New PartsConfirm that the new parts are intact and of the correct specifications and model. Apply any necessary lubrication, such as rust-proof oil or grease.Precise Installation and PositioningAccording to the drawings or technical specifications, accurately position the parts to avoid eccentricity or misalignment.Tightening Bolts and ConnectorsTighten the relevant bolts gradually and evenly according to the manufacturer's specified torque standards to ensure a secure connection without deformation.Installing Hydraulic SealsSeals, oil seals, etc. should be installed gently to avoid scratching or stretching. Use specialized installation tools if necessary.Replacing Disassembled AccessoriesRestore removed piping, protective covers, etc. to ensure the structural integrity of the equipment.5. Post-Replacement Inspection and CommissioningCheck SealingStart the hydraulic system and inspect the replaced parts for oil leaks or seepage.Functional TestPerform no-load and loaded test runs to verify smooth operation and normal clamping force.Check Operating ParametersMonitor key parameters such as oil pressure, temperature, and torque to ensure they are within normal ranges.Observe for Abnormal Sound and VibrationAfter replacement, there should be no abnormal noise or vibration. If any abnormality is detected, shut down the machine for inspection immediately.6. Precautions for Replacing Worn PartsSelect Qualified PartsPurchased parts must meet equipment specifications. Avoid using inferior or incompatible substitutes.Take Protective MeasuresWear protective gear during disassembly and installation to prevent oil splashing and mechanical damage.Record Maintenance InformationDetailed records of part replacement time, specifications, reasons, and operating status will facilitate equipment management and lifespan assessment.Avoid Reusing SealsOnce removed, seals should not be reused to ensure effective sealing.Environmental ProtectionDisposal of waste oil and used parts must comply with environmental regulations to prevent contamination.SummaryBucking unit part wear is an inevitable part of normal equipment operation. However, through scientific identification, standardized disassembly and assembly, replacement of high-quality parts, and rigorous commissioning and testing, equipment performance can be maximized and service life extended. A well-planned parts replacement cycle, combined with routine maintenance and management, can effectively reduce failure rates and ensure the continuity and safety of drilling operations. While replacing worn parts is a tedious task, each meticulous step is fundamental to ensuring stable equipment operation and must not be neglected.