With over 25 years‘ experience in power- and industrial-steam generation services, Tetra Engineering has developed a broad range of services to assist you in O&M activities that maximise performance and reliability.
Performance and Efficiency
How has your actual operating profile “drifted” since the plant / boiler was designed? Today’s plants can achieve near 60% efficiency when new and operating at the optimised load-case, but operating off-design can severely reduce efficiency and heat-rate. The challenge is twofold:
- How can you identify where the lost Watts are going?
- When found, what is the best way to win them back?
Typically, performance losses are associated with age-related degradation (for example fouling), off-design operation, or modifications that lead to changes in process conditions (for example, a GT upgrade that affects downstream HRSG performance).
Tetra Engineering has the range of experience for identifying which performance losses from among the multitude of causes are recoverable in considering feasibility and cost-effectiveness.
Optimised Non-Destructive Evaluation (NDE)
By design, ASME pressure parts (piping and boilers) are intended to be inspected at regular intervals. While many damage mechanisms can be detected visually, others are best discovered with various NDE methods, in particular:
- Fatigue cracking
- Corrosion-assisted cracking
- Flow-accelerated Corrosion
NDE contractors are expensive and usually don’t know your plant or process well enough to know which components are most at-risk for degradation and wear. If they inspect in the wrong places (i.e. where the rate of wear/damage is not highest), they’ll end up giving a false sense of security.
Optimised NDE means carefully selecting the locations that are most susceptible to damage, according to your components’ design and the way they are operated. Tetra Engineering has the requisite multi-disciplinary experience and tools (thermal simulation, life assessment, structural calculations….) in-house to help you get the most out of your NDE campaigns, by providing pre-outage planning, on-site supervision and post-inspection review.
Root Cause of Failure
Knowing the fundamental causes leading to failure is essential to mitigate the risk of the failure repeating. Tetra Engineering calls on an interdisciplinary team to assess the failure (or degradation) and determine the root cause.
The assessment may include:
- Operational Data Review
- Metallurgical Examination in a laboratory
- Mechanical Testing
- Chemical and Fuel Analysis
- Scanning Electron Microscopy
- Finite Element
- Boiler Process Modelling
Related and follow-up services for remediation may include fitness-for-service (FFS) or remaining life assessment, as needed.
The underlying objective is to “use” the failure as an opportunity to improve operational practices or identify potential design problems and thereby ensure long-term reliability of the steam cycle.