skip to Main Content

Developing Solutions for Failing Pitch Bearings on Wind Turbines

One of our most popular webinar topics is pitch bearings and efforts to reduce the failure rate and this costly problem for the industry. We’ve been quietly working on this problem over many years for owners and OEMs generally under the following process:

If you are having problems with pitch bearings, we can help. Get in contact with our experts on this part of the rotating machinery.

Just click here to ask an expert >>

Root Cause Analysis


Example fishbone diagram for eliminating failure causes to discover the real root cause

ONYX InSight has performed RCA’s on many pitch bearings. Common causes of failures identified include ellipse truncation, cage wear and surface fatigue, cracks originating at stress concentrations, and quality issues from poor induction hardening. We have a step by step RCA process to determine your root cause issue. Solutions are driven out of understanding the root cause.

Analysis of the Effect on Bearing Life


Model from RomaxWIND software

By changing the control strategy there can be a reduction of loading at the blade. But what is the impact on life and on other components? With RomaxWIND, our unique software that accounts for hub deflection during bearing analysis, ONYX can determine the benefits of control changes.

Life Extension

Compression strap testing and validation graphs

By adding compression to the bearing, the ONYX patented strap reduces the overall tensile stress below the range that causes and propagates the cracks. Testing and validation shows a 20% reduction in stress, extending bearing life.

Design Upgrade for Aftermarket Bearing

Design simulation model

ONYX InSight performs bearing modelling to inform re-design considerations such as contact angle, raceway curvature and cage design. Our engineering has allowed aftermarket bearings to an upgraded design to enter the market and fix the failure.

Custom Instrumentation

ONYX engineer using our Portable Vibration System (PVS) uptower

ONYX InSight offers custom instrumentation to measure pitch calibration, bearing fault frequencies, strain measurements, crack detection and pitch torque. These measurements can then be used to develop corrective actions, as well as to validate field retrofit solutions. We can support implementation of a condition monitoring solution.

Back To Top