1S2: Case Study: How Newkirk effect was detected during high vibration problem solving

Maciej Kloch, Diagnostic Team Manager, Grupa Azoty Prorem Mateusz Bujak, Sales Manager, Hansford Sensors

Description

Case study analysis of a 3 types Newkirk effects from 2 machines.

On 2 steam turbine Newkirk effect was detected during high vibration problem solving.

In 1st example there was a critical vibration level exceeded and machine was triped out from operation on protection system. This example was not obvious as during visual inspections there was no signs of rubbing. Further diagnostics was showing higher energy on 1x and polar plot supervision revealed one point friction on one side of shaft characteristic for Newkirk effect called hot spot. Thermal shaft bending process was then detected and proper diagnosis could been placed.

In example 2 in 17 MW turbine Newkirk effect detected on polar plot was periodical in 24 h cycles. It was possible to register 2 h spiral vibration effect in that process caused by oil carbonisation in high temperature. Leakage from steam pointed on oil sealing was burning additives in oil and effected in rubbing of the shaft from formed structures.

Bio - Maciej Kloch

Graduated vibrodiagnostics in 2005 at AGH University in Poland. Since then involved in vibration analysis with plenty of real life examples mainly from Chemical industry. Currently Manager of 25 people predictive maintenance team with vibroacoustic, technical control, NDT lab. Modal analysis expert with proven experience and B&K certificate. Personal interest in new methods of proactive maintenance.

Bio - Mateusz Bujak

Mateusz is a graduate of Mechanical Engineering and Mechatronics at AGH University in Krakow joined program with Illinois Institute of Technology in Chicago. Involved in vibration diagnostics for more than 10 years. Initially responsible for wind turbine remote diagnostics. Afterwards for commissioning of on-line systems and further for its development. Mateusz joined Hansford Sensors in 2009. He is currently responsible for Central, Eastern Europe, Scandinavia and Canada. During serving support to partners/customers always interested in challenging examples of troubleshooting and advanced analysis. Privately father of 2 young kids with interest in photography and high fidelity audio.