Mining Machinery Carburized Helical Gear – 58-62 HRC, 20CrMnTi

Mining machinery carburized helical gears are produced to operate in the most mechanically demanding gear applications in industry: continuous, heavy-load drives in bucket wheel excavators, large conveyor systems, ball mill drives, and other mining equipment that must run at high utilisation rates in environments with vibration, shock loading, and limited maintenance access. The performance requirements of these applications drive every aspect of the gear specification — material grade, carburising depth, core toughness, heat treatment process, and post-hardening accuracy.

Korea Ever-Power produces these gears in 18CrNiMo6 alloy steel, a nickel-chromium-molybdenum grade specifically developed for case-hardening applications requiring exceptional core toughness. The production process follows a defined sequence: forging, carburisation, plane and internal grinding, tooth grinding, and line cutting — each stage documented with traceability records. The finished gear is verified to DIN 3962 class 6 accuracy.

Before Sales

1. Customer provides detailed drawings.
2. Evaluate drawing, communicate technical and quality questions, then prepare quotation.
3. Face-to-face communication for unresolved technical points.
4. Prepare PPAP files for automotive and critical industrial programmes.

Design Cooperation (When No Drawing)

1. Customer provides application data without a detailed drawing.
2. Evaluate the application, simulate and optimise the gear design, produce a detailed drawing, then quote.
3. Prepare PPAP files.

In Process

1. Communicate technical questions identified during process planning.
2. Apply permanent traceability marking on each workpiece.
3. Complete production flow and transportation packing plan.

After-Sales

1. Follow the product's application condition in service.
2. Quality complaints: feedback within 24 hours; 8D report within 48 hours; field support if required.
3. Continuous improvement of machining processes, product quality, and lead time.
4. Annual customer visits to improve technical, quality, and commercial cooperation.

Bucket Wheel Excavators

Slewing ring drives, bucket wheel drives, and conveyor elevation drives in large bucket wheel excavators. These are among the largest and heaviest-loaded helical gear applications in existence, operating continuously at high utilisation rates in open-cast mining environments with vibration and shock loading.

Conveyor Head Drives

Large overland and in-pit conveyor head and tail drive gearboxes. These gearboxes operate at near-continuous duty and must achieve long service life between overhauls. The carburised 18CrNiMo6 tooth provides the surface pitting resistance required at the contact stresses imposed by high-capacity conveyor drives.

Ball Mill Drives

Ball mill main drive gearboxes in mineral processing plants. Ball mill drives start under full load and are subject to the mill's grinding torque throughout operation. The combination of carburised case hardness and tough core is essential to withstand the sustained high torque without pitting or tooth root fatigue.

Presses and Rolling Mills

Heavy press drives and rolling mill reduction gearboxes where the gear must carry peak loads during the working stroke or rolling bite while maintaining DIN 6 tooth accuracy for smooth, low-vibration operation between the load peaks.

Rudder and Marine Drives

Large vessel rudder drives and marine reduction gearboxes where high sustained torque and long service life between drydock overhauls are both required. 18CrNiMo6 carburised and ground to DIN 6 with classification society documentation for new-build vessels.

What should I do if I cannot identify the gear that failed?

Send us the damaged gear. Korea Ever-Power specialises in reverse engineering of large industrial and mining gears. Our team will measure the outer diameter, tooth count, helix angle, hand, pressure angle, profile shift coefficient, bore, hub, and face width from the physical gear, prepare a complete production drawing, and submit it for customer approval before cutting begins. For very large gears where shipping the full part is impractical, we can work from detailed dimensional reports and photographs supplemented by key measurement data provided by the customer's maintenance team.

What is the minimum order quantity for mining machinery helical gears?

MOQ depends on the specific gear size and configuration. Send us your drawing or sample, specify the required quantity, and we will confirm the minimum. For large mining gears at module 9 or above, MOQ is typically one pair (pinion and wheel together), since the mating geometry must be verified together. For smaller configuration sizes, minimum quantities may be higher.

How is fast delivery achieved without finished stock?

Korea Ever-Power maintains a large inventory of tools, raw material billets and forgings in the most common alloy grades (including 18CrNiMo6), and semi-finished blanks in common size ranges. Production begins immediately upon order confirmation. For urgent replacement gears in mining applications, contact our team directly — we will assess the production queue and confirm the fastest available lead time for your specific configuration.

Can gears not shown on this site be manufactured?

Yes. Everything listed on the Korea Ever-Power website represents the categories of gear we produce — not a fixed catalogue of available sizes. We can manufacture any mining helical gear configuration in 18CrNiMo6 or other suitable alloy steels, at any module and tooth count achievable within the production capabilities shown in the specification tables. Custom gear designs are our core capability, not an exception to it.

How is the lowest price achieved for mining helical gear orders?

For mining helical gears, the primary price factors are module size (which determines machine capacity and grinding time), material specification, accuracy grade, face width, and required documentation. Quantity influences per-unit cost — larger orders allow amortisation of setup and heat treatment batch costs across more parts. Providing a complete drawing with all parameters at the enquiry stage, rather than adding requirements during negotiation, produces the most accurate initial quotation and avoids additional cost at the change order stage. Contact our team with your drawing and required quantity for a detailed price breakdown.

"We maintain a large-format bucket wheel excavator and required replacement reduction gearbox helical gear pairs in 18CrNiMo6 at DIN 6 — the OEM had quoted a 26-week lead time. Korea Ever-Power reverse-engineered the specification from our worn gear set, provided the production drawing for approval within 6 working days, and delivered within our required maintenance window. Heat treatment records and CMM reports accompanied the delivery."

Kim Byeong-cheol  |  Chief Engineer, Gyeongnam Open Cast Mining Co.  ·  Q1 2026

"We design ball mill drives for mineral processing plants and qualified Korea Ever-Power as a supplier for carburised helical gear sets in 18CrNiMo6. The 8D after-sales protocol was demonstrated during a quality issue on the second batch — root cause identified and corrective action implemented within the committed 48 hours. Subsequent deliveries have all been within specification."

Park Sung-woo  |  Drivetrain Engineer, Incheon Mineral Processing Equipment  ·  Q3 2025

"We supply conveyor head drives to an iron ore mining operation and source the main helical gear pairs from Korea Ever-Power. The traceability code on each gear links back to the heat treatment furnace run number and raw material batch. This traceability has been essential for our ISO quality system audit — the auditor was satisfied with the documentation level without any additional requests."

Lee Sang-hoon  |  Production Manager, Busan Mining Equipment Co.  ·  Q4 2025

"We needed an M9 carburised helical pinion to replace a failed unit in a press reduction gearbox with no drawing available. Ever-Power measured the mating wheel on site, calculated the pinion geometry to match, and produced a replacement pinion in 18CrNiMo6 at DIN 6. The new pinion meshed correctly with the existing wheel on first installation. Press returned to production within the planned shutdown window."

Choi Dong-seok  |  Plant Maintenance Director, Ulsan Heavy Press Manufacturing  ·  Q2 2025

"We qualified Korea Ever-Power for 18CrNiMo6 carburised helical gears through our PPAP process. The design cooperation service was useful — our application data did not include a finished gear drawing, only the gearbox input/output parameters. Ever-Power's team produced the optimised gear geometry, drew it up, and submitted for our approval before any production began. PPAP Level 3 package was accepted at first submission."

Yoon Jae-hyuk  |  Drivetrain Qualification Engineer, Daejeon Mining Systems  ·  Q1 2026