Asset Care Counts Piping Vibration Analysis
Piping Vibration Analysis
Vibration induced fatigue failures of pipework are a major concern for a range of asset owners due the risks associated with:
- Safety (sudden release of hazardous or flammable pressurised fluids);
- Production down time;
- Corrective action cost;
- Environmental impacts (loss of containment);
- Statutory Risk.
Data quoted by the Energy Institute from the offshore industry have shown that piping vibration and fatigue account for over 20% of all hydrocarbon releases in the North Sea offshore industry. Data quoted for Western European plants indicate that 10-15% of pipework failures in these plants are caused by vibration induced fatigue.
Trends indicated increasing incidence of vibration related fatigue failures in piping systems both on offshore and petrochemical plants due to changes in plant design. The main change contributing to failures are:
- Increasing flow rates, higher flow velocities and the resulting flow turbulence, which drives vibration.
- Greater use of thin walled pipework (e.g. duplex stainless-steel alloys) resulting in more flexible pipework and higher stress concentrations, particularly in small bore connections.
Energy Institute Guidelines (EIG)
The EIG provides asset owners with a guide to VIF threat assessment and risk mitigation. The assessments in the EIG can be split into two assessment types.
The first is Proactive Assessment, which provides a high-level screening method for qualitatively and quantitatively assessing the risk of VIF on new or existing plant.
The second assessment type is Reactive Assessment, which provides guidelines for dealing with areas where there are known vibration problems.
Each of the assessments draws on methods described in Technical Modules (TM) within the EIG.
The EIG recommends conducting basic piping vibration measurements (TM-07) as part of the Proactive Assessment process. The measurements are intended to be basic, so that non-specialist personnel may be employed to conduct these first pass assessments. The results of the measurements are classified in one of four categories:
- High Frequency Vibration – Seek Specialist Advice
Solution – ALS Piping Vibration Analyser
In the past, plant operators and contractors used data logging instruments, combined with analysis software to perform the basic vibration measurements on piping systems.
This method requires specialist personnel and substantial setup time to be able to conduct the TM-07 Basic Vibration Assessment. In plants were there are multiple measurement points (>10) and these measurement points are far apart (>30 m). Multiple setup locations are required which meant the process of collecting data was time consuming and not cost effective.
Upon understanding these inefficiencies ALS has designed and commercialised a handheld piping vibration.
The analyser contains a customised Graphical User Interface (GUI) which allows non-specialist users to record and evaluate piping vibration data to the Energy Institute Guidelines.
The analyser allows non-specialist ALS personnel to conduct infield piping vibration data collection and analysis on process piping to the requirements of EIG TM-07. The system also allows technicians to store data for further in-depth analysis by ALS Engineers utilising existing software platforms.
To date ALS has successfully deployed this new technology to a range of customers including a proactive assessment of vibration induced fatigue threats on a multi-national LNG producers small bore process pipework network. This initiative has produced significant cost savings associated with data collection and analysis. We believe this product is a vital tool to limit asset owner risk whilst reducing cost associated with vibration programs.
Our Asset Integrity and Reliability teams consist of engineers, scientists, inspectors and technicians who can promptly assist you with the most complex projects.
We believe in confidence in industrial assets, delivering this through our broad suite of services including:
- Non-destructive testing (traditional and advanced);
- Condition monitoring;
- Engineering consulting (civil, mechanical, materials, structural).
Combined with the latest technologies, ALS continues to deliver cost effective solutions.Download PDF