Small bore piping is the most likely source of fatigue failure associated with rotating and reciprocating machinery.
This service is a proven approach to identify and mitigate high risk vibration sources. As a result, the facility and ownership team will avoid the safety, operational and environmental penalties associated with liquid leaks or gas releases on small bore piping.
Background: Vibration Risks on Rotating Equipment
Fatigue failures due to vibration on small bore piping are the single highest “bad actor” we come across in our field work at refineries, compressor and pump stations, and offshore production facilities. In other words, MOST failures we see around the world on rotating equipment are caused by small bore piping – also called small bore attachments, branch connections, or small diameter appurtenances.
They represent the highest risk of capital loss and safety of all the problems we come across. The reasons for this is that small bore attachments are not given sufficient attention at the design stage and are difficult to properly assess during operations.
> Click here to link to articles and case studies illustrating the challenges associated with small bore piping (SBP) or small bore attachments.
To address these problems, owners need a risk assessment process that can evaluate whether each small bore attachment will fail.
BETA's assessment and screening program is easy to use and can help your operations staff identify and reduce integrity risks due to SBP. The following service has been tailored to support small sites as well as large production complexes.
|Level 0 - Pre-screening|
If the refinery or production facility has significant amounts of small bore piping (e.g., over 500 locations), a pre-screening activity may be a practical approach to reduce the number of areas to look at during the field assessment.
Level 1 – Plant-Wide Screening and Risk Assessment
The first level is a process of screening higher risk attachments from low risk ones, in order to:
- Know where your risks are
- Plan and prioritize the effort on the higher risk items
BETA’s trained vibration specialists will conduct this fast assessment on all small bore attachments. Our proven process will ensure all potential hazards are identified.
For large refineries or installations where customers have dedicated vibration technicians, BETA can provide technical training, testing processes, and help coordinate a facility-wide inspection program.
If over screening guideline and ASME guideline, move to Level 2.
Level 2 – Stress Analysis of High Risk Locations (and Complex Geometries)
It is likely that a percentage of small bore attachments will not pass Level 1 screening. These higher risk locations will be assessed in greater detail, because fatigue failures can occur due to excessive alternating stress levels. Vibration measurements do not provide the stress levels; they provide an indication of stress. To know if the attachment will likely fail, we need to calculate stress.
This level of assessment takes the information obtained from the screening performed in Level 1 plus additional component details and calculates the stress and allowable vibration on each individual attachment. This analysis will determine how close the level of vibration (measured in the Level 1 screening) is to the endurance limit of the small bore configuration.
If calculations reveal a high risk of failure on a particular attachment, recommendations for modifications are discussed with the client to remediate the problem. If vibration is different at different operating conditions, or different during upset conditions, then Level 3 is recommended.
Level 3 – Transient Vibration Analysis
Small bore attachments can fail when exposed to transient conditions, such as, machinery start-up, shut-down, throttling to control flow, or when operating across a wide range of conditions.
> Example of transient conditions on small bore piping
If transient conditions are present, then Level 3 may be required. BETA will come to the site and measure vibration on the high risk locations that could face fatigue failure during transient conditions. BETA will use a multi-channel data collection to capture the required information and employ specialized analysis software to evaluate vibration risks and calculate fatigue or remaining life of SBP.
Please contact us, info@BetaMachinery.com, or (+1) 403-245-5666 for further information and to help address your questions.