BOMCO Drawworks and Spare Parts Classification

Core Purpose Description

This document focuses on BOMCO (Baoji Oilfield Machinery Co., Ltd.) drawworks series (JC-90, JC-70, JC-50, JC-40 and their DB/D variants, as well as JC90DB1) and their matching spare parts. These products are exclusively compatible with BOMCO drilling rig systems, tailored for oilfield drilling enterprises, drilling rig maintenance service providers, and oilfield equipment rental companies. They address pain points of equipment shutdown, low drilling efficiency, and safety hazards caused by harsh drilling environments (high pressure, high vibration, dust), long-term high-load operation, and component wear/failure in drawworks operation. All products comply with API Spec 7K "Drilling and Well Servicing Equipment" and GB/T 23505-2009 "Drilling Rig Drawworks" standards, ensuring reliable power transmission, stable lifting performance, and safe operation of drilling rigs, providing authoritative technical support for efficient and safe oilfield drilling operations.

1. BOMCO Drawworks Main Units

This series of drawworks features high power input, large load-bearing capacity, and dual-speed adjustment, solving pain points of insufficient lifting force and low speed adaptability in deep well and ultra-deep well drilling. Suitable for onshore and offshore drilling rigs requiring high-power hoisting operations, matching BOMCO drilling rig systems.

2. Key Shaft Assemblies & Rotating Components

This category includes drum shaft assemblies and matching bearings/seals, which are core rotating components of drawworks, ensuring stable power transmission. They solve pain points of shaft jamming and power transmission failure caused by bearing wear and seal damage. Suitable for BOMCO JC series drawworks maintenance and replacement.

3. Lubrication System Components

This series of components ensures effective lubrication and heat dissipation of drawworks moving parts, solving pain points of component wear acceleration and failure caused by insufficient lubrication and oil contamination. Suitable for BOMCO JC series drawworks lubrication system maintenance and upgrading.

4. Air Control System Components

This category includes air control valves, cylinders, and matching connectors, ensuring stable operation of drawworks brake and clutch systems. They solve pain points of brake failure and control inaccuracy caused by component wear and air leakage. Suitable for BOMCO JC series drawworks air control system maintenance.

5. General Fasteners & Auxiliary Components

This series of components provides reliable fixing and auxiliary functions for drawworks, solving pain points of component loosening and functional failure caused by vibration and harsh environment. Suitable for BOMCO JC series drawworks overall maintenance and spare part replacement.

Field Fault Maintenance Case

Case 1: BOMCO JC90DB1 Drawworks Bearing Damage Caused by Lubrication Contamination

Fault Phenomenon: During deep well drilling with BOMCO JC90DB1 drawworks, abnormal continuous sharp noise suddenly appeared in the drum area, and the bearing end temperature rose rapidly from the normal 65℃ to 95℃ within 20 minutes. The drilling operation was forced to stop immediately to prevent the bearing from seizing and causing secondary damage to the drum shaft assembly.

Detailed Inspection Process: 1. Safety Preparation: First, cut off the power supply of the drawworks and the matching lubrication system, hang a "No Operation Under Maintenance" warning sign around the maintenance area, and wait for the bearing to cool down naturally (avoid direct cooling with water to prevent thermal deformation of the shaft and bearing); 2. Preliminary Positioning: Use an infrared thermometer to measure the temperature of each component of the drum shaft assembly, and confirm that the high-temperature area is concentrated at the 2360CA/W33 bearing position; use a stethoscope to listen to the noise, and confirm that the abnormal noise source is consistent with the high-temperature position; 3. Disassembly Inspection: a) Use special tools to remove the drum end hood and bearing end cover in sequence, and observe that the bearing outer ring has obvious blue discoloration (caused by high temperature); b) Use a bearing puller to remove the bearing, and find that the rolling elements are severely worn, with pitting and peeling phenomena, and the inner and outer ring raceways have irregular wear marks; c) Extract the lubricating oil from the gearbox, observe that the oil is turbid and contains black metal particles, and send the oil sample for detection, the oil cleanliness reaches NAS 12 level, which is far lower than the standard requirement of NAS 7 level; d) Check the lubrication system components, and find that the oil suction filter (model TFA-630X180F-Y) filter element is severely blocked by impurities, and the filter surface has obvious oil stains and metal debris accumulation; 4. Auxiliary Verification: Check the gearbox air filter, which is intact and has no damage, eliminating the possibility of external dust entering in large quantities; check the lubrication pipeline, which is unblocked and has no leakage, confirming that the main cause of oil contamination is the blocked filter element.

Root Cause Analysis: 1. The oil suction filter element was not replaced according to the specified maintenance cycle (every 500 operating hours). After long-term use, the filter element was blocked by impurities and metal particles in the lubricating oil, losing the filtering function; 2. The blocked filter element could not effectively filter the impurities in the oil, leading to the continuous circulation of contaminated lubricating oil in the system and entering the 2360CA/W33 bearing; 3. The impurities in the oil caused abrasive wear to the bearing rolling elements and raceways, increasing the friction between the bearing components, which in turn led to a sharp rise in temperature and the generation of abnormal noise.

Complete Solution: 1. Safety Protection: Maintenance personnel wear professional protective equipment (high-temperature resistant gloves, goggles, anti-skid shoes) to avoid scalding and mechanical injury during operation; 2. Disassembly of Damaged Components: a) Use a bearing puller to remove the worn 2360CA/W33 bearing from the drum shaft, and pay attention to protecting the shaft surface during disassembly to avoid scratches; b) Remove the blocked oil suction filter (TFA-630X180F-Y), and disconnect the inlet and outlet pipelines of the filter, plugging the pipeline ports with clean rubber plugs to prevent impurities from entering; c) Disconnect the lubrication pipeline connected to the bearing chamber, and seal the pipeline port temporarily; 3. Cleaning Treatment: a) Use diesel oil to thoroughly clean the drum shaft surface, especially the bearing installation position, polish the surface with fine sandpaper to ensure the surface roughness Ra ≤ 0.8μm, and dry it with clean compressed air; b) Open the gearbox oil drain valve, drain all the old contaminated lubricating oil, and use diesel oil to flush the gearbox inner cavity twice, then use compressed air to blow dry the inner cavity; c) Flush the lubrication pipeline with new API-specified industrial gear oil (ISO VG 460) to remove residual impurities in the pipeline, and drain the flushing oil; d) Clean the filter housing of the oil suction filter with diesel oil, and dry it thoroughly; 4. Component Replacement: a) Select a new 2360CA/W33 bearing (part number 530301143403802000) that matches the JC90DB1 drawworks, apply a thin layer of lithium-based grease on the bearing inner ring and the shaft installation surface, and use a press to press the bearing into place (avoid knocking to prevent bearing damage); b) Install a new TFA-630X180F-Y oil suction filter element, and reassemble the filter to the original position, ensuring that the pipeline connection is tight and there is no leakage; c) Reconnect the lubrication pipeline, and use a torque wrench to tighten the pipeline connectors according to the specified torque (20-25N·m); 5. Lubricating Oil Replacement: Inject new API-specified industrial gear oil (ISO VG 460) into the gearbox to the specified oil level (1/2-2/3 of the oil window), and check for oil leakage at the oil filler port and drain valve; 6. Assembly & Debugging: a) Install the bearing end cover and drum end hood in sequence, and tighten the fastening bolts with a torque wrench according to the specified torque (30-35N·m); b) Restore the power supply, start the lubrication system first, check the oil pressure (normal range 0.3-0.5MPa) and oil circulation, and confirm that the lubrication is normal; c) Start the drawworks for no-load operation, monitor the bearing temperature and noise in real time: within 30 minutes of operation, the bearing temperature should rise steadily and not exceed 70℃, and there should be no abnormal noise; d) Conduct load test: gradually apply 50%, 80%, and 100% of the rated load to the drawworks, and each load level operates for 1 hour. During the period, monitor the bearing temperature (stable at 65-70℃) and lubrication system operation, and confirm that all indicators are normal; 7. Post-Maintenance Inspection: After the drawworks operates stably for 2 hours, stop the machine to check the bearing end cover, lubrication pipeline connectors, and gearbox for oil leakage; check the oil suction filter for abnormal pressure difference (normal pressure difference ≤ 0.1MPa); 8. Preventive Maintenance Measures: a) Formulate a fixed maintenance plan: strictly replace the oil suction filter element every 500 operating hours, replace the gearbox lubricating oil every 1500 operating hours, and test the oil cleanliness every 3 months; b) Daily inspection: Add the oil suction filter status and bearing temperature to the daily inspection list of the drawworks, and record the data; c) Personnel Training: Train the on-site operators and maintenance personnel on the importance of filter element replacement and the judgment method of abnormal bearing temperature, ensuring that potential faults are found and handled in time.

Maintenance Effect: After the above maintenance, the BOMCO JC90DB1 drawworks resumed normal operation. During continuous 72-hour deep well drilling, the bearing temperature remained stable at 65-70℃, no abnormal noise was generated, and the lubrication system operated smoothly. The follow-up 1-month tracking showed that all indicators of the drawworks were normal, and no similar faults occurred, ensuring the continuity and safety of deep well drilling operations.

Case 2: BOMCO JC-70 Drawworks Air Control System Leakage Failure

Fault Phenomenon: During the drilling operation of BOMCO JC-70 drawworks, the brake response was obviously slow (the response time increased from the normal 0.5s to 2s), and the air pressure of the air control system dropped rapidly from the rated 0.8MPa to 0.4MPa within 5 minutes when the brake was continuously used. The insufficient air pressure led to the decrease of brake force, which posed a great safety hazard to the drilling operation.

Detailed Inspection Process: 1. Safety Preparation: Stop the drawworks operation, keep the air compressor in standby state, and ensure that the maintenance operation is carried out under safe air pressure (reduce the system pressure to 0.2MPa); 2. Air Pressure Leakage Detection: a) Apply soapy water to the air control system pipelines, connectors, and FESTO lock cylinder (DNC-KPO100X25) joints, and observe that there are continuous bubbles at the cylinder rod end and 3 air pipeline connectors, indicating air leakage; b) Use an air flow meter to detect the total leakage of the system, and the leakage rate reaches 0.8m³/min, which exceeds the standard limit of 0.2m³/min; 3. Cylinder Disassembly Inspection: Disassemble the FESTO lock cylinder (DNC-KPO100X25), take out the piston and seal ring, and find that the fluororubber seal ring on the piston has obvious wear and aging cracks, and the seal surface is uneven; the inner wall of the cylinder tube has no obvious wear; 4. Pipeline and Connector Inspection: Check the air pipeline and connectors, and find that 3 connectors are loose (the torque is only 10N·m, lower than the specified 18N·m); the pipeline has no cracks or aging, but there is a small amount of water stains on the inner wall of the pipeline; 5. Air Source Inspection: Check the air compressor's air treatment unit, and find that the air dryer is not working, resulting in the compressed air containing a lot of moisture (the dew point is 15℃, exceeding the standard requirement of -20℃).

Root Cause Analysis: 1. The air dryer of the air source system failed to work, resulting in a large amount of moisture in the compressed air entering the air control system. The moisture corroded and aged the fluororubber seal ring of the FESTO lock cylinder for a long time, leading to seal ring wear and air leakage at the cylinder rod end; 2. The air control system pipelines were not fixed firmly, and the long-term high vibration of the drawworks caused the loosening of the pipeline connectors, resulting in air leakage at the connectors; 3. The combination of cylinder leakage and connector leakage led to rapid air pressure drop in the system, and the insufficient air pressure caused the slow response of the brake system.

Complete Solution: 1. Safety Protection: Maintenance personnel wear protective goggles and anti-static gloves to prevent air pressure impact and pipeline debris injury; 2. Cylinder Seal Replacement: a) Disassemble the FESTO lock cylinder (DNC-KPO100X25) completely, take out the old worn fluororubber seal ring, and clean the piston, cylinder tube, and end cover with anhydrous ethanol to remove moisture and impurities; b) Select a new fluororubber seal ring matching the cylinder model, apply a thin layer of air cylinder special lubricating grease on the seal ring, and install it on the piston in sequence; c) Reassemble the cylinder, ensuring that the piston moves smoothly without jamming, and tighten the cylinder end cover bolts with a torque wrench (specified torque: 15-18N·m); 3. Air Source Improvement: a) Repair the failed air dryer; if it cannot be repaired, replace it with a new air dryer of the same model, and debug it to ensure that the dew point of the compressed air reaches -20℃, meeting the system requirements; b) Drain all the moisture in the air tank of the air compressor, and clean the air filter of the air compressor; 4. Pipeline and Connector Treatment: a) Tighten the 3 loose pipeline connectors with a torque wrench according to the specified torque (18N·m); b) Apply thread sealant (PTFE type) to the connector threads to enhance the sealing performance; c) Fix the air pipeline with anti-vibration pipe clamps at intervals of 1.5m to reduce the impact of drawworks vibration on the pipeline and connectors; d) Use anhydrous ethanol to clean the inner wall of the pipeline to remove residual water stains; 5. System Assembly & Debugging: a) Reconnect all components of the air control system, and apply soapy water to each joint to check for air leakage (no bubbles generated is qualified); b) Start the air compressor, adjust the system pressure to the rated 0.8MPa, and keep it for 30 minutes. The pressure drop is ≤ 0.05MPa, meeting the standard requirements; c) Start the drawworks, test the brake response time (restored to 0.5s), and test the brake force under rated load, which meets the design requirements; d) Continuously use the brake for 10 minutes, and the system air pressure remains stable at 0.75-0.8MPa, with no obvious pressure drop; 6. Post-Maintenance Inspection: After the drawworks operates stably for 4 hours, recheck the air control system for air leakage, the cylinder operation status, and the air dryer working status, and confirm that all are normal; 7. Preventive Maintenance Measures: a) Establish a daily inspection system: drain the moisture in the air tank every shift; check the air control system connectors for looseness and the cylinder for air leakage every day; b) Regular maintenance: calibrate the air dryer every 6 months to ensure its normal operation; replace the cylinder seal ring every 12 months (regardless of wear status) to prevent aging leakage; c) Record management: establish a maintenance record form for the air control system, recording the inspection results, maintenance content, and replacement parts information.

Maintenance Effect: After the maintenance and improvement, the brake response speed of BOMCO JC-70 drawworks was restored to the normal level, the system air pressure remained stable during continuous operation, and the brake force met the drilling operation requirements. The follow-up 2-week tracking showed that the air control system operated normally without air leakage and pressure drop faults, eliminating the safety hazard and ensuring the safe and efficient progress of drilling operations.

Procurement Guide & Call to Action

All BOMCO drawworks and spare parts listed in this document comply with API Spec 7K and GB/T 23505-2009 standards, with genuine quality and complete certification. When purchasing, please confirm the matching drawworks model (JC-90/JC-70/JC-50/JC-40 series and their variants), the specific component's drawing number/part number, and the drilling working conditions (onshore/offshore, deep well/shallow well) to ensure accurate matching. Our professional technical team provides one-on-one technical consultation services, covering product selection, on-site installation guidance, fault diagnosis, and maintenance training. For detailed product parameters, material performance reports, API certification documents, and procurement quotes, please contact us at your convenience. We are committed to providing you with high-quality, genuine BOMCO drawworks and spare parts, as well as professional after-sales support, to ensure the efficient, stable and safe operation of your drilling rigs.

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