Klingelnberg P 40

$900,000 - $1,300,000 Updated 2026-03-17

Key Specifications

Max Workpiece ⌀

400 mm (15.75 in)

max module

10 mm

min module

1 mm

max face width

80 mm (3.15 in)

bevel gear system

Palloid and Cyclo-Palloid

grinding method

Generating and profile grinding

Overview

The Klingelnberg P 40 is a CNC bevel gear grinding machine designed for the precision hard-fine finishing of Palloid and Klingelnberg Cyclo-Palloid spiral bevel gears with a maximum workpiece diameter of 400 mm (15.75 in). Manufactured by Klingelnberg GmbH in Hückeswagen, Germany, the P 40 is positioned at the heart of Klingelnberg's bevel gear grinding portfolio, serving automotive axle gear manufacturers, helicopter gearbox builders, railway traction drive producers, and industrial bevel gearbox shops requiring DIN 1–4 / AGMA 12–14 quality on finished bevel gears. Klingelnberg is the world leader in Palloid bevel gear technology — a system defined by a conical hobbing cutter that produces a conjugate tooth form across the full face width — and the P 40 is the primary machine for finish-grinding Palloid and Cyclo-Palloid bevel gear sets after case hardening.

Bevel gear grinding with the P 40 uses a dressable CBN or aluminum oxide grinding wheel in a continuous indexing (generating) or plunge (profile) grinding cycle, depending on the application. Klingelnberg's proprietary KIMOS (Klingelnberg Integrated Manufacturing and Optimization System) software drives the entire bevel gear manufacturing workflow from design through grinding and inspection. Gear geometry, ease-off topography (the deviation map defining how the real tooth surface differs from the theoretical conjugate), and contact pattern targets are defined in KIMOS and translated directly into P 40 grinding programs, eliminating the need for manual parameter calculation. The closed-loop integration between P 40 grinders and Klingelnberg P series precision bevel gear measuring centers (such as the P 40 measuring machine) enables automatic correction cycles that maintain consistent ease-off and contact pattern quality across production runs.

The P 40 is built on a Klingelnberg-designed machine base with high thermal mass and active thermal compensation to minimize thermal drift during extended production grinding runs. Grinding spindle speeds reach up to 6,000 RPM with a direct-drive spindle unit for minimal vibration transmission to the cutting zone. The workpiece spindle accommodates both ring gears and pinions in the 400 mm capacity range, with automatic workpiece changing capability when combined with Klingelnberg's automation systems. The machine's intuitive touchscreen HMI provides direct access to KIMOS functions including ease-off analysis, correction preview, and process monitoring without requiring the operator to use a separate engineering workstation.

Klingelnberg's P 40 is most commonly encountered in complete bevel gear manufacturing cells paired with a Klingelnberg C 40 or C 50 spiral bevel gear cutting machine (for soft cutting before hardening) and a Klingelnberg P 40 or P 65 bevel gear measuring center (for quality verification and closed-loop correction). This integrated Klingelnberg system approach is favored by automotive rear axle gear producers, helicopter gearbox OEMs, and railway traction gear manufacturers who want to control the full bevel gear manufacturing process — cutting, grinding, and inspection — within a single technology ecosystem with one supplier's application engineering support.

The P 40 competes with the Gleason Phoenix 280G and Oerlikon G 35 in the mid-capacity bevel gear grinding segment. New P 40 machines are priced between $900,000 and $1,300,000 depending on configuration, automation, and KIMOS software packages. The machine's integration with Klingelnberg's closed-loop bevel gear manufacturing system and the depth of Klingelnberg's bevel gear application expertise are key value drivers beyond the machine hardware itself.

Full Specifications

Parameter	Value
Max Workpiece Diameter	400 mm (15.75 in)
Max Module	10 mm
Min Module	1 mm
Max Face Width	80 mm (3.15 in)
Bevel Gear System	Palloid and Cyclo-Palloid
Grinding Method	Generating and profile grinding
Grinding Spindle Speed	Up to 6,000 RPM
Spindle Drive	Direct-drive grinding spindle
Dressing	On-machine CNC diamond dressing
Workpiece Types	Spiral bevel ring gears and pinions
Axes	6 CNC axes
CNC Control	Siemens SINUMERIK with KIMOS
Machine Weight	14,000 kg (30,865 lb)
Gear Quality	DIN 1–4 / AGMA 12–14

Specifications sourced from klingelnberg.com — verified 2026-03-28

Strengths & Limitations

Strengths

Klingelnberg's KIMOS closed-loop system integrates bevel gear design, grinding programming, and inspection data to automatically correct P 40 grinding parameters, maintaining ease-off and contact pattern quality with minimal operator intervention
Palloid and Cyclo-Palloid bevel gear system provides theoretically conjugate tooth geometry across the full face width, enabling higher load capacity and smoother meshing than face-hobbed alternatives for a given module and size
DIN 1–4 / AGMA 12–14 quality achievable with the P 40 meets the demands of automotive hypoid rear axle gears, helicopter bevel gearbox sets, and railway traction gear pairs where the highest accuracy is mandatory
Direct-drive grinding spindle minimizes vibration at the cutting zone, critical for achieving ultra-smooth tooth surfaces (Ra < 0.4 µm) on bevel gears where surface texture directly affects gear noise and efficiency
Complete Klingelnberg bevel gear ecosystem (cutting + grinding + measuring) under a single technology platform simplifies application engineering, reduces process development time, and ensures tooling and software compatibility
On-machine diamond dressing enables complex ease-off topography corrections in the grinding wheel profile, implementing precise contact pattern control without manual wheel dressing adjustments

Limitations

At $900,000–$1,300,000, the P 40 is a major investment that requires a consistent backlog of precision bevel gear grinding work — mid-volume or general job shops rarely generate sufficient bevel gear volume to justify this investment
Klingelnberg's Palloid/Cyclo-Palloid technology is an interdependent system: P 40 grinders are most effective paired with Klingelnberg C series cutters and P series measuring machines, creating significant technology lock-in
Bevel gear grinding is a highly specialized process requiring extensive application engineering knowledge for ease-off design, contact pattern optimization, and grinding parameter selection — operator competence demands are high

Best For

Automotive rear axle and hypoid bevel gear manufacturers grinding ring and pinion sets for passenger car and light truck rear axles where contact pattern, NVH performance, and fatigue life are critical Helicopter and aerospace gearbox manufacturers grinding spiral bevel gear sets for main rotor, tail rotor, and accessory gearboxes where quality, weight, and surface finish requirements are the most demanding in industry Railway traction drive manufacturers grinding bevel gear sets for axle-mounted traction gearboxes and bogie drives requiring long service life under high cyclic loads in demanding environmental conditions Industrial bevel gearbox producers grinding replacement and new-build Palloid bevel gear sets for right-angle drives, conveyor drives, and heavy machinery applications

Frequently Asked Questions

01 What is the Palloid bevel gear system and why does Klingelnberg specialize in it?

The Palloid system, developed by Klingelnberg, uses a conical hobbing cutter (the Palloid cutter) to generate spiral bevel gears with a theoretically conjugate tooth form across the full face width. Unlike face-hobbed bevel gears (Gleason's standard), Palloid gears have a continuous spiral tooth with constant normal tooth depth, which provides more uniform load distribution along the face width and higher load capacity per unit of material. Klingelnberg has built its entire bevel gear technology ecosystem — cutters, grinding machines, and measuring systems — around the Palloid and Cyclo-Palloid system, giving them deep application expertise but also creating a complete system dependency.

02 What is an 'ease-off' in bevel gear manufacturing and how does KIMOS manage it?

An ease-off is a topographic map showing how the actual tooth surface of a bevel gear deviates from the theoretical conjugate (perfect) tooth surface. Bevel gear manufacturers intentionally introduce controlled ease-off deviations — crowning, bias correction, pressure angle modification — to control contact pattern position and shape under operating loads and housing/shaft deflections. KIMOS allows engineers to design a target ease-off, simulate the resulting contact pattern under load, generate the P 40 grinding program to achieve that ease-off, and compare measured ease-off data from the inspection machine to the target, automatically generating corrections if needed.

03 Does the P 40 grind both ring gears and pinions?

Yes, the P 40 grinds both spiral bevel ring gears and pinions up to 400 mm in maximum diameter. Ring gears are typically the larger member (face gear) and pinions are the smaller member (shaft or straddle-mounted) in a bevel gear set. Both are ground in the P 40 using the same grinding wheel and machine kinematics, with different workholding fixtures for the ring gear (chuck or fixture plate) and pinion (centers or chuck). Klingelnberg recommends grinding matched sets on the same P 40 to maximize contact pattern consistency.

04 How does the P 40 integrate with Klingelnberg inspection machines?

The P 40 is designed to operate in closed loop with Klingelnberg's P series gear measuring centers (such as the P 40 precision bevel gear measuring machine). After grinding a sample gear, it is transferred to the measuring machine where KIMOS measures the actual tooth surface topography and compares it to the target ease-off. Deviations are calculated and automatically transmitted back to the P 40 as machine parameter corrections. The next grinding cycle incorporates these corrections, maintaining ease-off and contact pattern quality without manual calculation or operator judgment. This closed loop is the core of Klingelnberg's quality system.

05 What is the difference between Klingelnberg P 40 and P 65?

The Klingelnberg P 40 and P 65 are siblings in the Cyclo-Palloid bevel gear grinding range, differentiated primarily by workpiece capacity. The P 40 handles maximum workpiece diameters of 400 mm, while the P 65 extends capacity to 650 mm for larger bevel gears used in heavy trucks, agricultural machinery, and industrial drives. Both use the same KIMOS software platform and Cyclo-Palloid grinding technology. The P 65 is physically larger, heavier, and more expensive, targeted at larger bevel gear applications that exceed the P 40's capacity.