Precision Bevel Gear – M0.15 to M2.2, AGMA 13, 5 HT Routes

Applied to low-carbon alloy steels (20CrMnTi, 20CrNiMo, 9310). Carbon enrichment of the tooth surface to 0.8–1.0% followed by quenching produces 58–62 HRC case over a tough low-carbon core. Post-quench distortion is corrected by tooth grinding (mandatory for AGMA 13 / JGMA 1). The combination of hard case, tough core, and ground tooth flanks is the highest-performance route for precision bevel gears in load-bearing applications.

Best for: automotive differentials, military drives, servo gearheads requiring maximum load and top accuracy

High-frequency induction heating hardens the tooth surface rapidly without prolonged furnace cycles. Applicable to through-hardening steels (40Cr, 42CrMo). The hardened zone is shallower and more localised than a carburised case, and the process introduces compressive residual stresses at the tooth surface that improve fatigue life. Dimensional distortion is lower than carburising because only the surface is heated. For large gears where furnace capacity is a constraint, or for gears requiring selective surface hardening of the tooth only, induction is the practical route.

Best for: medium-load drives, selective surface hardening, gears too large for carburising furnace

Nitrogen diffusion at 500–580°C — below the transformation temperature — produces a very hard, thin surface layer (0.2–0.5 mm) without the dimensional distortion of quenching. For precision bevel gears that must achieve AGMA 12 or 13 without post-hardening grinding, nitriding is the preferred route: finish-machine the tooth to final accuracy, nitride, and the gear leaves the furnace dimensionally within the target tolerance. The surface hardness after nitriding (700–1000 HV / approximately 60–68 HRC equivalent) is very high. Applied to nitriding steels (31CrMoV9, 34CrAlMo5) or stainless steel grades.

Best for: AGMA 12–13 without post-nitriding grinding; large gears; corrosion-sensitive environments

Through-hardening of medium-carbon alloy steels (42CrMo, 40Cr) followed by tempering produces uniform hardness from surface to core — typically 280–340 HB. No case-core differentiation; the entire tooth cross-section is at equal hardness. This provides good impact resistance (the core does not fail in a brittle mode under shock) and allows field repair by re-machining the tooth profile after wear, since the hardness is consistent through the section. The accuracy achievable after through-hardening plus tooth grinding is fully compatible with AGMA 13.

Best for: shock-loaded drives, agricultural and construction equipment, gears requiring field re-machinability

For non-standard materials — 17-4PH stainless (age hardening H900), 440C stainless (oil quench hardening), titanium alloys (stress relieving), or special alloys per customer specification — the heat treatment route is engineered to that material's specific phase transformation or precipitation hardening mechanism. Korea Ever-Power's engineering team selects and documents the heat treatment cycle for each material variant, with the time-temperature curve retained per batch as part of the precision bevel gear's production record.

Best for: 17-4PH, 440C, titanium alloys, and other materials with non-standard heat treatment requirements

Gear accuracy grades define the permissible errors in four parameters: single pitch deviation, total cumulative pitch deviation, total profile deviation, and total helix deviation (for spiral gears). Each grade specifies a maximum value for each parameter as a function of module and gear diameter. The practical effect of accuracy grade on the application is as follows:

📈 Servo Drives & Motion Control

Precision bevel gear stages in servo-driven angular positioning systems must have low and consistent backlash, low transmission error, and dimensional stability over temperature and load cycles. Any periodic angular error at the gear mesh frequency appears as a position ripple in the servo loop, potentially destabilising the control. AGMA 13 gears with carburised and ground tooth flanks are the specification for high-performance servo angle drives.

📷 High-Speed Printing Presses

Cross-drives in offset printing presses synchronise multiple print cylinder shafts. Transmission error in the bevel gear stage appears as a repeating register error in the printed image — misalignment of colour separations or pattern repeat errors visible to the naked eye. AGMA 13 precision bevel gears with nitrided or ground flanks are the standard specification for high-speed commercial printing drives.

⚙ CNC Machine Tools

Angle head attachments, dividing head bevel drives, and rotary axis bevel stages in CNC machine tools. The angular position accuracy of the tool at the workpiece depends on the transmission error of every gear stage in the drive chain. AGMA 12–13 precision bevel gears in the machine tool's bevel stage are a prerequisite for achieving the angular positioning accuracy published in the machine's specification sheet.

🔯 Military Targeting & Optics

Weapon elevation and azimuth drives, targeting pod gimbals, and optical instrument angle drives in military equipment require the lowest achievable transmission error to maintain pointing accuracy under load, vibration, and shock. JGMA 1 / AGMA 13 in nitrided stainless or carburised alloy steel with full material traceability and non-magnetic material requirements for optical instrument applications.

🔩 Semi-Conductor & Electronics

Wafer handling robot angle drives and precision stage positioning systems in semi-conductor fabrication require bevel gears with low particle generation, cleanroom-compatible materials, and stable backlash over millions of operating cycles. Aluminium or stainless gears at AGMA 12–13 with hard anodising or passivation are standard for these applications.

🚗 Automotive OEM

Precision differential ring-and-pinion sets, electric power steering bevel stages, and automatic transmission auxiliary drives where the combination of AGMA 12 accuracy, TS16949 quality system, and PPAP documentation defines the supplier qualification requirements. Carburised 20CrMnTi or 20CrNiMo with ground flanks is the standard specification.

What is the business scope and main export products of Korea Ever-Power?

Korea Ever-Power is a manufacturer specialising in CNC machining, custom gear production, and independent development of multi-category transmission products. Main export products include bevel gears (the full range covered by this website), gear racks, spur gears, helical gears, couplings, universal joints, gearboxes, and related power transmission components. The precision bevel gear series represents the highest-accuracy subset of the bevel gear range, targeting applications where DIN 5 through ISO 6 accuracy is a design requirement rather than an optional upgrade.

How do you select the heat treatment route for a precision bevel gear?

The selection involves three criteria evaluated together. First, the material: low-carbon alloy steels require carburising; medium-carbon steels can be through-hardened or induction-hardened; nitriding steels are designed for the nitriding route; special alloys follow their specific phase transformation or precipitation hardening schedule. Second, the required surface hardness: carburising achieves 58–62 HRC; nitriding achieves 60–68 HRC equivalent at the surface but in a thinner layer; through-hardening achieves 28–36 HRC uniformly. Third, post-hardening dimensional distortion tolerance: if the gear must achieve AGMA 13 and tooth grinding after hardening is acceptable (and often necessary), carburising is the typical route; if the gear must achieve AGMA 12 without post-hardening grinding, nitriding is often preferred because the lower process temperature minimises distortion. Our engineering team documents the route selected for each order in the production engineering package.

How quickly can a precision bevel gear sample be obtained?

For standard configurations held in stock — common module and ratio combinations in frequently ordered materials — samples are available in three to five working days. For configurations produced to order, the sample lead time follows the production sequence and is typically two to four weeks. Submit the drawing or sample part with the enquiry and we will confirm whether the configuration is in stock or requires production, and give the lead time accordingly. For urgent sample requirements, contact our team directly and we will confirm the fastest available path.

Can you provide a product catalogue in PDF format?

Yes. Our product documentation includes PDF datasheets for the precision bevel gear series covering the available module range, accuracy grades, material options, and standard heat treatment routes. For specific configurations, our technical department produces and issues a dimensioned drawing showing the proposed geometry for customer review before production. Request the relevant documentation through our contact page and our team will send it within one working day.

Can the gear be designed to work at shaft intersection angles other than 90°?

Yes. Bevel gears are not restricted to 90° shaft intersection — the pitch cone angle of each gear is determined by the ratio and the shaft intersection angle together, and any angle between approximately 45° and 135° is achievable within the bevel gear geometry. For angles other than 90°, the pitch cone geometry changes on both gears and the blank dimensions differ from the 90° standard. Provide the shaft intersection angle in your drawing or specify it clearly in the enquiry; our engineering team calculates the correct cone geometry and confirms it in the production drawing before cutting begins. Contact us with your intersection angle and ratio and we will confirm feasibility.

"We manufacture servo-driven angular positioning stages for semiconductor equipment. The M1.0 AGMA 13 precision bevel gears from Ever-Power eliminated the position ripple we were seeing with our previous AGMA 10 supplier. The CMM report they supply with each batch documents the tooth spacing error on every gear — we use these reports directly in our process validation records."

Kim Tae-jun  |  Motion Control Engineer, Suwon Precision Systems  ·  Q2 2025

"We specified M0.8 nitrided 31CrMoV9 precision bevel gears for a printing press cross-drive — nitriding to avoid post-hardening grinding while maintaining AGMA 12 accuracy. Ever-Power's engineering team confirmed the nitriding route was correct for this material and specified the case depth. Register accuracy in the press improved measurably after fitting the new gear set."

Oh Hyun-jae  |  Press Drive Engineer, Gyeonggi Commercial Printing  ·  Q4 2025

"We needed M1.5 alloy steel precision bevel gears with carburising and quenching for a CNC angle head. Sample arrived in four days from stock — faster than we expected at this accuracy grade. The heat treatment curve and dimensional report were both included. First batch in production for six months, positioning accuracy unchanged from commissioning."

Jeon Sang-won  |  Machine Tool Design Engineer, Daegu Precision Tooling  ·  Q1 2026

"We source AGMA 12 precision bevel gears in 42CrMo through-hardened for an electric vehicle auxiliary drive. The through-hardening route allows our service engineers to assess tooth wear by hardness measurement in the field — not possible with a case-hardened gear. Ever-Power correctly identified this as the reason for our material choice without us having to explain it."

Lim Jae-hwan  |  Powertrain Component Engineer, Incheon EV Systems  ·  Q3 2025

"We design precision gimbal drives for military thermal imaging pods. The bevel gear pairs are M0.5 17-4PH stainless at JGMA 1, age-hardened H900. The material-specific heat treatment route — age hardening rather than standard quenching — was correctly specified by Ever-Power's team before production. Four completed programmes, each passing our acceptance test for transmission error on first submission."

Cha Byeong-woo  |  Optical Systems Engineer, Busan Defence Optics  ·  Q2 2026