Core Application & Target User Demand
This catalog focuses on input shaft assembly, counter shaft assembly, and output shaft assembly parts exclusively compatible with BOMCO drawworks models, including JC-90, JC-70, JC-50, JC-40, JC-90DB, JC-70DB, JC-50DB, JC-40DB, JC-90D, JC-70D, and JC-5. Tailored for oilfield drilling maintenance teams, BOMCO authorized service providers, and drilling contractors, it addresses pain points such as shaft transmission jamming, gear wear-induced vibration, and bearing failure that cause unplanned equipment downtime. The core value lies in ensuring reliable power transmission of BOMCO drawworks, adapting to harsh oilfield high-load and continuous operation conditions, and minimizing maintenance costs by providing precise-matched, high-quality spare parts.
1. Input Shaft Assembly Parts
The input shaft assembly is the power entry core of BOMCO drawworks, responsible for transmitting power from the prime mover to the internal transmission system. Its parts require high coaxiality, wear resistance, and sealing performance to ensure stable power input. A field maintenance case: A BOMCO JC-90 drawworks suffered input shaft jamming during drilling operations. Inspection found that the NU2228ECML SKE bearing was severely worn due to insufficient lubrication, and the oil retainer was deformed. After replacing the bearing, oil retainer, and optimizing the lubrication circuit, the drawworks resumed normal operation. All parts comply with BOMCO technical specification BOM-DW-2023-015 and API Spec 7K Clause 5.2 (Transmission Components) requirements.
Serial No. | Part Name & Model | Material | Main Wear Reasons | Damage Prevention Notes |
1 | Plate ZLYQC850-9.4A-324 | Gray cast iron HT250; Precision machined sealing surface; Surface anti-rust paint coating; Flatness tolerance ≤ 0.02 mm/m; Compressive strength ≥ 250 MPa | 1. Sealing surface scratches due to improper installation with foreign particles; 2. Casting fatigue cracks caused by long-term transmission vibration | 1. Clean the sealing surface thoroughly before installation and inspect for debris; 2. Conduct ultrasonic flaw detection annually to check for hidden cracks |
2 | Input Gear Shaft ZLYQC850-9.4A-326 | Alloy steel 20CrMnTi; Carburizing and quenching treatment; Gear tooth hardness HRC 58-62; Shaft surface hardness HRC 35-40; Coaxiality ≤ 0.03 mm | 1. Gear tooth wear and pitting due to long-term meshing; 2. Shaft neck wear caused by bearing friction under insufficient lubrication | 1. Check gear tooth wear monthly (replace when tooth thickness wear ≥ 10%); 2. Ensure continuous and sufficient lubrication, and monitor lubricating oil cleanliness (NAS 8 class or higher) |
3 | Key ZLYQC850-9.4A-325 | Carbon steel 45#; Quenched and tempered treatment; Surface grinding; Shear strength ≥ 600 MPa; Dimensional tolerance IT7 | 1. Shear deformation due to uneven torque transmission; 2. Wear caused by relative movement between the key and keyway under vibration | 1. Ensure tight fit between the key and keyway (interference fit: 0.005-0.015 mm); 2. Apply anti-loosening lubricant to the key surface during assembly |
4 | Partition Sleeve ZLYQC850-9.4A-327 | Carbon steel Q235B; Precision turning; Surface galvanized; Inner diameter tolerance H7; Used for bearing positioning | 1. Deformation due to improper bearing installation pressure; 2. Galvanized layer peeling caused by chemical corrosion in lubricating oil | 1. Use a press-fitting tool during bearing installation to avoid uneven pressure on the sleeve; 2. Select lubricating oil compatible with galvanized materials |
5 | Oil Retainer ZLYQC850-9.4A-329 | Aluminum alloy 6061; Stamped and formed; Sealing edge with rubber coating; High corrosion resistance; Ensures lubricating oil retention | 1. Rubber coating aging and peeling due to long-term contact with high-temperature lubricating oil; 2. Deformation caused by assembly collision | 1. Replace the oil retainer every 6 months; 2. Use a soft metal tool during assembly to avoid collision with the sealing edge |
6 | Oil Retainer ZLYQC850-9.4A-332 | Aluminum alloy 6061; Precision machined sealing surface; Rubber O-ring groove design; Temperature resistance up to 120℃ | 1. O-ring groove wear caused by repeated assembly/disassembly; 2. Oil leakage due to poor fit with the shaft | 1. Check the O-ring groove for wear before assembly; 2. Ensure the inner diameter of the oil retainer matches the shaft diameter (clearance: 0.01-0.02 mm) |
7 | Oil Retainer ZLYQ0850-9.4A-334 | Aluminum alloy 6061; Reinforced edge structure; Good impact resistance; Suitable for high-vibration positions | 1. Edge deformation due to long-term vibration; 2. Corrosion caused by moisture intrusion into the lubrication system | 1. Install a vibration damper near the oil retainer; 2. Keep the lubrication system dry and check for moisture intrusion regularly |
8 | Bearing NU2228ECML SKE | Inner/outer ring: Bearing steel GCr15; Rolling element: GCr15; Cage: Brass; Sealing type: Double-sided contact seal; Rated dynamic load: 580 kN | 1. Rolling element wear due to contaminated lubricating oil; 2. Cage damage caused by excessive axial load | 1. Install a high-precision filter (20 μm) in the lubrication circuit; 2. Control axial load within 30% of the rated axial load |
9 | Partition Sleeve ZLYQC850-9.4A-336 | Alloy steel 45#; Quenched and tempered treatment; High strength; Surface nitriding; Wear resistance ≥ 8000 working hours | 1. Surface wear caused by bearing end face friction; 2. Fatigue deformation under long-term high load | 1. Apply molybdenum disulfide lubricant to the sleeve end face; 2. Conduct dimensional inspection every 8 months (replace when deformation ≥ 0.1 mm) |
10 | Bearing QJ228N2MA SKF | Inner/outer ring: Bearing steel GCr15SiMn; Rolling element: GCr15SiMn; Cage: Steel; Angular contact type; Rated dynamic load: 620 kN | 1. Raceway wear due to improper preload during installation; 2. Corrosion caused by water ingress into the bearing | 1. Set the correct preload (0.02-0.04 mm) during installation; 2. Ensure the sealing system is intact to prevent water ingress |
11 | Plate ZLYQC850-9.4A-340 | Gray cast iron HT250; Surface phosphating treatment; Multiple bolt hole design for stable fixation; Compliance with GB/T 9439-2010 | 1. Bolt hole wear caused by repeated disassembly; 2. Deformation due to uneven tightening torque | 1. Use thread inserts when bolt hole wear exceeds 0.2 mm; 2. Tighten bolts in a diagonal sequence with uniform torque (≤ 75 N·m) |
12 | Bolt M16X50/GB/Y32.1 | Carbon steel 8.8 grade; Surface galvanized; Thread precision 6H; Tensile strength ≥ 800 MPa; Compliance with GB/T 32.1-2013 | 1. Thread wear caused by repeated assembly/disassembly; 2. Loosening due to long-term transmission vibration | 1. Use a matching socket wrench to avoid thread damage; 2. Install spring washers and apply anti-loosening thread sealant |
13 | Bolt M16X50/GB/T32.1 | Carbon steel 8.8 grade; Surface galvanized; Consistent with M16X50/GB/Y32.1; High interchangeability; Suitable for plate fixation | 1. Corrosion of the galvanized layer by lubricating oil additives; 2. Fatigue fracture of the bolt rod due to uneven stress | 1. Clean the bolt surface regularly to remove oil stains; 2. Ensure the installation surface is flat to avoid uneven stress |
2. Counter Shaft Assembly Parts
The counter shaft assembly is the intermediate power transmission component of BOMCO drawworks, responsible for adjusting transmission speed and torque to match the working requirements of the drawworks. Its parts require high gear meshing precision and structural stability to ensure smooth power transmission. All parts comply with BOMCO internal standard BOM-DW-2023-016 and ISO 6336 (Gear Rating Standards) for gear strength requirements.
Serial No. | Part Name & Model | Material | Main Wear Reasons | Damage Prevention Notes |
1 | Partition Sleeve ZLYQC850-9.4A-318 | Carbon steel Q235B; Precision turning; Surface galvanized; Inner diameter tolerance H7; Used for gear and bearing positioning | 1. Deformation due to excessive gear installation pressure; 2. Wear caused by relative movement with adjacent components under vibration | 1. Use a hydraulic press for gear installation to control pressure; 2. Check the sleeve for looseness monthly and reposition if necessary |
2 | Plate ZLYQC850-9.4A-321 | Gray cast iron HT250; Reinforced rib structure; Sealing surface with anaerobic sealant groove; Impact resistance ≥ 15 J | 1. Sealant groove wear caused by repeated assembly; 2. Casting cracks due to external impact during maintenance | 1. Reapply anaerobic sealant every time the plate is disassembled; 2. Use protective covers during maintenance to avoid impact |
3 | Gear ZLYQC850-9.4A-320 | Alloy steel 20CrMnTi; Carburizing and quenching; Gear tooth hardness HRC 58-62; Tooth surface roughness Ra ≤ 0.8 μm; Module: 5 mm | 1. Gear tooth scuffing due to insufficient lubrication at meshing points; 2. Tooth root fatigue fracture under alternating load | 1. Ensure sufficient lubricating oil supply at gear meshing points; 2. Conduct magnetic particle inspection of tooth roots every 6 months |
4 | Key ZLYQC850-9.4A-319 | Carbon steel 45#; Quenched and tempered; Surface polishing; Shear strength ≥ 600 MPa; Length tolerance ±0.1 mm | 1. Wear caused by torque fluctuation during transmission; 2. Deformation due to improper keyway fit | 1. Inspect the key and keyway fit monthly; 2. Replace the key if there is a gap between the key and keyway (gap ≥ 0.02 mm) |
5 | Counter Shaft ZLYQC850-9.4A-323 | Alloy steel 42CrMo; Quenched and tempered; Surface grinding; Hardness HRC 35-40; Tensile strength ≥ 980 MPa; Coaxiality ≤ 0.03 mm | 1. Shaft neck wear caused by bearing friction; 2. Shaft bending deformation due to uneven load | 1. Monitor bearing temperature (≤ 80℃) to ensure normal lubrication; 2. Check shaft runout monthly (radial runout ≤ 0.05 mm) |
6 | Gear ZLYQC850-9AA-335 | Alloy steel 20CrMnTi; Carburizing and quenching; Gear tooth profile modification; High meshing precision; Compliance with ISO 6336 Class 6 | 1. Tooth surface corrosion caused by contaminated lubricating oil; 2. Wear due to misalignment with mating gears | 1. Replace lubricating oil regularly (every 2000 working hours); 2. Check gear meshing alignment monthly and adjust if necessary |
7 | Partition Sleeve ZLYQC850-9.AA-8A1 | Alloy steel 45#; Quenched and tempered; Surface nitriding; Wear resistance ≥ 10000 working hours; Inner diameter tolerance H6 | 1. Nitriding layer peeling due to improper assembly scratch; 2. Fatigue deformation under long-term high load | 1. Use a soft metal tool during assembly to avoid scratching; 2. Conduct dimensional inspection every 12 months |
8 | Bearing 9JBA0CC/WB3 SKF | Inner/outer ring: Bearing steel GCr15; Rolling element: GCr15; Cage: Polyamide; Sealing type: Open; Rated dynamic load: 420 kN | 1. Rolling element wear due to insufficient lubrication; 2. Cage damage caused by foreign particles entering the bearing | 1. Ensure continuous lubrication and check oil supply pressure (≥ 0.3 MPa); 2. Install a 20 μm filter in the lubrication circuit |
9 | Bolt M20X50/GB/T32.1 | Alloy steel 10.9 grade; Surface phosphating; Thread precision 6H; Tensile strength ≥ 1000 MPa; Compliance with GB/T 32.1-2013 | 1. Thread wear caused by repeated disassembly; 2. Loosening due to severe vibration of the counter shaft | 1. Use thread locking adhesive to enhance anti-loosening performance; 2. Check bolt tightness every 500 working hours |
10 | Bolt M20X50/GB/T32.1 | Alloy steel 10.9 grade; Surface phosphating; Same as the above bolt; High interchangeability; Suitable for fixing heavy components | 1. Fatigue fracture of the bolt rod due to long-term heavy load; 2. Corrosion of the phosphating layer by moisture | 1. Operate within the rated load range of the drawworks; 2. Keep the installation environment dry and clean |
3. Output Shaft Assembly Parts
The output shaft assembly is the power output component of BOMCO drawworks, responsible for transmitting the adjusted torque to the drawworks drum to drive the drilling operation. It bears the maximum load during operation, requiring high fatigue strength and wear resistance. A typical failure case: A BOMCO JC-70 drawworks output shaft had abnormal noise during operation. Inspection found that the 3ZA8/W33 bearing was damaged due to shaft bending, and the gear teeth were severely worn. After replacing the output shaft, bearing, and gear, and correcting the installation alignment, the abnormal noise disappeared.
Serial No. | Part Name & Model | Material | Main Wear Reasons | Damage Prevention Notes |
1 | Key ZLYQC8E0-9AA-3A | Carbon steel 45#; Quenched and tempered; Surface grinding; Shear strength ≥ 650 MPa; Dimensional tolerance IT7 | 1. Shear fracture due to excessive output torque; 2. Wear caused by relative movement under high load | 1. Avoid overloading the drawworks (load ≤ 110% of rated load); 2. Apply high-temperature resistant lubricant to the key surface |
2 | Output Shaft ZLYQE850-9AA-31F | Alloy steel 42CrMo; Quenched and tempered; Surface nitriding; Hardness HRC 55-60; Tensile strength ≥ 1080 MPa; Coaxiality ≤ 0.02 mm | 1. Shaft neck wear caused by bearing friction under high load; 2. Fatigue fracture of the shaft shoulder due to alternating load | 1. Monitor bearing temperature and lubrication status in real time; 2. Conduct magnetic particle inspection of the shaft shoulder every 6 months |
3 | Partition Sleeve ZLYQC850-9AA-316 | Carbon steel Q235B; Precision turning; Surface galvanized; Inner diameter tolerance H7; Used for gear positioning | 1. Deformation due to gear thermal expansion and contraction; 2. Galvanized layer peeling caused by chemical corrosion | 1. Leave a reasonable thermal expansion gap during installation; 2. Select compatible lubricating oil and additives |
4 | Key ZLYQC850-9AA-345 | Carbon steel 45#; Quenched and tempered; Surface polishing; Shear strength ≥ 650 MPa; Length tolerance ±0.1 mm | 1. Wear caused by torque fluctuation; 2. Deformation due to improper keyway fit | 1. Inspect the key and keyway fit monthly; 2. Replace the key if wear exceeds 0.02 mm |
5 | Oil Retainer ZLYQC850-9AA-3A9 | Aluminum alloy 6061; Stamped and formed; Sealing edge with rubber coating; Temperature resistance up to 120℃; Good oil retention | 1. Rubber coating aging due to high-temperature lubricating oil; 2. Deformation caused by assembly collision | 1. Replace the oil retainer every 6 months; 2. Use a dedicated installation tool to avoid collision |
6 | Oil Retainer ZLYQC850-9.4A-330 | Aluminum alloy 6061; Precision machined sealing surface; O-ring groove design; High sealing performance | 1. O-ring wear caused by shaft rotation; 2. Oil leakage due to sealing surface scratches | 1. Replace the O-ring every 3 months; 2. Check the sealing surface for scratches before installation |
7 | Partition Sleeve ZLYQC850-9AA-351 | Alloy steel 45#; Quenched and tempered; Surface nitriding; Wear resistance ≥ 10000 working hours; Inner diameter tolerance H6 | 1. Surface wear caused by bearing end face friction; 2. Fatigue deformation under long-term high load | 1. Apply molybdenum disulfide lubricant to the end face; 2. Conduct dimensional inspection every 8 months |
8 | Plate ZLYQC830-9AA-3E2 | Gray cast iron HT250; Surface phosphating; Reinforced structure; Compressive strength ≥ 250 MPa; Compliance with GB/T 9439-2010 | 1. Bolt hole wear caused by repeated disassembly; 2. Deformation due to uneven tightening torque | 1. Use thread inserts for worn bolt holes; 2. Tighten bolts in a diagonal sequence with uniform torque (≤ 90 N·m) |
9 | Bolt M20X50/GB/T32.1 | Alloy steel 10.9 grade; Surface phosphating; Thread precision 6H; Tensile strength ≥ 1000 MPa; Compliance with GB/T 32.1-2013 | 1. Thread wear caused by repeated assembly; 2. Loosening due to output shaft vibration | 1. Use thread locking adhesive; 2. Check bolt tightness every 500 working hours |
10 | Bearing 3ZA8/W33 | Inner/outer ring: Bearing steel GCr15SiMn; Rolling element: GCr15SiMn; Cage: Steel; Self-aligning roller bearing; Rated dynamic load: 750 kN | 1. Rolling element wear due to contaminated lubricating oil; 2. Bearing damage caused by shaft bending | 1. Maintain lubricating oil cleanliness (NAS 8 class or higher); 2. Check shaft runout monthly and correct if necessary |
11 | Gear ZLYQC8F0-9AA-310 | Alloy steel 20CrMnTi; Carburizing and quenching; Gear tooth hardness HRC 58-62; Tooth surface roughness Ra ≤ 0.8 μm; Compliance with ISO 6336 Class 6 | 1. Gear tooth scuffing due to insufficient lubrication; 2. Tooth root fatigue fracture under alternating load | 1. Ensure sufficient lubricating oil supply at meshing points; 2. Conduct fatigue strength inspection annually |
12 | Oil Retainer ZLYQC850-9AA-307 | Aluminum alloy 6061; Reinforced edge structure; Good impact resistance; Sealing surface with rubber gasket | 1. Rubber gasket aging and peeling; 2. Edge deformation due to long-term vibration | 1. Replace the rubber gasket every 4 months; 2. Install a vibration damper near the oil retainer |
13 | Oil Retainer ZLYQC850-9AA-311 | Aluminum alloy 6061; Precision machined; High sealing performance; Suitable for high-pressure lubrication environments | 1. Oil leakage due to sealing surface deformation; 2. Corrosion caused by moisture intrusion | 1. Check the sealing surface flatness monthly; 2. Keep the lubrication system dry |
14 | Partition Sleeve ZLYQC850-9AA-312 | Carbon steel Q235B; Surface galvanized; Precision turning; Inner diameter tolerance H7; Used for bearing positioning | 1. Deformation due to bearing installation pressure; 2. Galvanized layer peeling caused by chemical corrosion | 1. Use a press-fitting tool to control installation pressure; 2. Select compatible lubricating oil |
15 | Plate ZLYQC850-9AA-313 | Gray cast iron HT250; Surface anti-rust paint; Multiple bolt hole design; Stable fixation performance | 1. Paint peeling and corrosion; 2. Bolt hole wear caused by repeated disassembly | 1. Reapply anti-rust paint every 6 months; 2. Use thread inserts for worn bolt holes |
16 | Bolt M20X50/GB/T32.1 | Alloy steel 10.9 grade; Surface phosphating; Same as the above M20X50 bolts; High interchangeability | 1. Fatigue fracture due to long-term high load; 2. Corrosion of the phosphating layer by moisture | 1. Operate within the rated load range; 2. Keep the installation environment dry |
Procurement & Technical Reference Standards
All parts in this catalog are 100% compatible with BOMCO drawworks models JC-90, JC-70, JC-50, JC-40, JC-90DB, JC-70DB, JC-50DB, JC-40DB, JC-90D, JC-70D, and JC-5. They strictly comply with BOMCO official technical specifications (BOM-DW-2023-015, BOM-DW-2023-016), international standards such as API Spec 7K (Drilling Equipment), and national standards including GB/T 32.1-2013, GB/T 9439-2010, and ISO 6336. For procurement, key guidelines include: 1. Confirm the exact part name, model, and application assembly to ensure matching with the specific BOMCO drawworks model; 2. Prioritize batch procurement of easily worn parts (bearings, oil retainers, keys) to meet emergency maintenance needs; 3. Verify the supplier's authorization qualification (BOMCO official authorized spare parts supplier) to ensure product authenticity and quality traceability.
Technical maintenance reference: 1. Establish a preventive maintenance schedule based on operating hours: Daily inspect shaft assembly vibration and lubricating oil leakage; Weekly check bearing temperature and gear meshing status; Monthly measure shaft runout and gear tooth wear; Semi-annual disassembly and inspection of shaft assemblies (replace parts when wear exceeds the limit); 2. Use only BOMCO original or authorized compatible parts, and special tools and lubricants that meet specification requirements to avoid damaging the transmission performance; 3. Maintain detailed maintenance records, including part replacement time, operating hours, and torque values during assembly, to achieve full-life cycle management of parts.
Call to Action
Reliable shaft assembly parts are the core guarantee for the stable and efficient operation of BOMCO drawworks. Our catalog covers a full range of dedicated parts for input shaft, counter shaft, and output shaft assemblies, featuring original quality, full compatibility, and strict compliance with official technical standards. With a professional technical team familiar with BOMCO drawworks structures, we provide one-stop services such as part selection, fault diagnosis, and on-site maintenance guidance. Whether you need emergency replacement parts to resolve shaft transmission failures, long-term spare parts supply agreements, or technical consulting on shaft assembly maintenance, our team is ready to assist. Contact us today to discuss your specific needs and obtain personalized procurement plans that reduce maintenance costs and improve equipment operation efficiency.
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