Fossil Power Archives

Structural Integrity Associates | Wireless Sensor Node Featured Image

High Energy Piping Monitoring

May 11, 2022/in Combined Cycle, Company News, Fossil Power, Jason Van Velsor, Monitoring Case Study, News, Steve Gressler/by Structural Integrity

High Energy Piping Monitoring

SI moves beyond the pilot application of a High Energy Piping monitoring program designed to reduce operational risk and optimize maintenance activities.

SI has successfully implemented the initial application of an integrated monitoring solution that provides insight into damage evolution and operational risk using real-time data and automated engineering intelligence. This solution will assist in the optimization of maintenance activities and downtime, helping utilities get the most out of their O&M budgets. “This is a decisive step toward a more modern asset management approach that will lower O&M cost for our clients,” said Steve Gressler, Vice President, SI Energy Services Group, a division of Structural Integrity Associates, Inc. (SI) focused on power plant asset integrity.

Informed by decades of material performance knowledge, the SI team has refined a proprietary risk-ranking method to optimize sensor placement and deliver a high-value monitoring platform supported by the PlantTrack™ asset data management platform. The integration of monitoring information into the platform further enhances equipment asset integrity data to simplify stakeholder decision making. The SI solution incorporates various sensors working on a distributed wireless network to feed real-time data to SI’s state-of-the-art algorithms and is also capable of integrating with existing plant data historians to pull in other valuable operational data. The outcome is a cost-effective damage monitoring approach to focus resources and the timing of comprehensive field inspections.

“The architecture enables asset managers to obtain real-time feedback, alerts, and trends that clearly link actual operating conditions to the lifecycle of critical components.,” said Jason Van Velsor, Director of Integrated Monitoring Technology at SI.

“We have supported clients with asset integrity insights for decades and now offer enhanced monitoring technology that will help automate risk management for high energy piping and help obtain the most value out of field inspection and other maintenance activities during outages.”

Unique Features of the SI Solution include:

Design and application of a monitoring program that focuses on safety and reliability and is consistent with guidance contained in the ASME B31.1 regulatory code.
Expert assessment (or Gap Analysis) to optimize monitoring including health checkups to validate optimum monitoring for plant operation.
Decades of material analysis insights as algorithms to expertly inform decision making.
Customized automated alerts to notify operators of abnormal or undesirable operating conditions affecting the life of high-energy components.

Contact Steve or Jason to learn more (info@structint.com)

Read Our Related News and Views Story

News and Views Volume 49, Attemperator Monitoring with Wireless Sensors

Structural Integrity Associates | News and Views, Volume 51 | Pitting Corrosion in Conventional Fossil Boilers and Combined Cycle:HRSGs

News & Views, Volume 51 | Materials Lab Featured Damage Mechanism

April 19, 2022/in Company News, Heat Recovery Steam Generator (HRSG), Materials Laboratory, News and Views, Wendy Weiss/by Structural Integrity

PITTING CORROSION IN CONVENTIONAL FOSSIL BOILERS AND COMBINED CYCLE/HRSGS

By: Wendy Weiss

Pitting is a localized corrosion phenomenon in which a relatively small loss of metal can result in the catastrophic failure of a tube. Pitting can also be the precursor to other damage mechanisms, including corrosion fatigue and stress corrosion cracking. Pits often are small and may be filled with corrosion products or oxide, so that identification of the severity of pitting attack by visual examination can be difficult.

Mechanism

Pitting is a localized corrosion attack involving dissolution of the tube metal surface in a small and well-defined area. Pitting corrosion can occur in any component in contact with water under stagnant oxygenated conditions. Pitting in economizer tubing is typically the result of poor shutdown practices that allow contact with highly-oxygenated, stagnant water. Pitting also may occur in waterwall tubing as a result of acidic attack stemming from an unsatisfactory chemical cleaning or acidic contamination.

Pits that are associated with low pH conditions tend to be numerous and spaced fairly close together. The pits tend to be deep-walled compared to the length of the defect. A breakdown of the passive metal surface initiates the pitting process under stagnant oxygenated conditions. A large potential difference develops between the small area of the initiated active pit (anode) and the passive area around the pit (cathode). The pit will grow in the presence of a concentrated salt or acidic species. The metal ion salt (M+A-) combines with water and forms a metal hydroxide and a corresponding free acid (e.g., hydrochloric acid when chloride is present). Oxygen reduction at the cathode suppresses the corrosion around the edges of the pit, but inside the pit the rate of attack increases as the local environment within the pit becomes more acidic. In the event that the surfaces along the walls of the pit are not repassivated, the rate of pit growth will continue to increase since the reaction is no longer governed by the bulk fluid environment. Pitting is frequently encountered in stagnant conditions that allow the site initiation and concentration, allowing the attack to continue.

NEWS August 19 - HRSG Forum Major Cycle Chemistry Aspects for HRS copy

HRSG Forum: Major Cycle Chemistry Aspects for HRSGs

August 18, 2021/in Barry Dooley, Heat Recovery Steam Generator (HRSG), News/by Structural Integrity

‘SI is proud to have SI Expert and Senior Associate, Dr. Barry Dooley presenting at the HRSG Forum on August 19^that 11 am (EST).

TOPIC: Introduction to the Key Cycle Chemistry Features for HRSG Reliability

The basic rules for providing optimum cycle chemistry control for HRSGs will be outlined. The latest statistics from over 100 HRSG plants worldwide will show how the lack of basic cycle chemistry controls leads to the major failure/damage mechanisms. The following two presentations will provide information on what is acceptable for the two top situations involving monitoring iron and continuous instrumentation.

Click here for more information

News & Views, Volume 49 | Materials Lab Featured Damage Mechanism: Soot Blower Erosion

April 20, 2021/in Combined Cycle, Fossil Power, Heat Recovery Steam Generator (HRSG), Materials Laboratory, News and Views, Wendy Weiss/by Structural Integrity

By: Wendy Weiss

Soot blower erosion (SBE) is caused by mechanical removal of tube material due to the impingement on the tube wall of particles entrained in the “wet” blower steam. As the erosion becomes more severe, the tube wall thickness is reduced and eventually internal pressure causes the tube rupture.

Mechanism

SBE is due to the loss of tube material caused by the impingement of ash particles entrained in the blowing steam on the tube OD surface. In addition to the direct loss of material by the mechanical erosion, SBE also removes the protective fireside oxide. (Where the erosion only affects the protective oxide layer on the fireside surface, the damage is more properly characterized as erosion-corrosion.) Due to the parabolic nature of the oxidation process, the fireside oxidation rate of the freshly exposed metal is increased. The rate of damage caused by the steam is related to the velocity and physical properties of the ash, the velocity of the particles and the approach or impact angle. While the damage sustained by the tube is a function of its resistance to erosion, its composition, and its operating temperature, the properties of the impinging particles are more influential in determining the rate of wall loss.

News & Views, Volume 49 | Piping Fabricated Branch Connections

April 20, 2021/in Ben Ruchte, Combined Cycle, Fossil Power, Heat Recovery Steam Generator (HRSG), Materials Lab, News and Views/by Structural Integrity

By: Ben Ruchte

Fabricated branch connections represent a common industry issue in combined cycle plants. Many are vulnerable to early damage development and have experienced failures. Despite these challenges, a well-engineered approach exists to ensure that the baseline condition is fully documented and a life management plan is put in place to help reduce the overall risk to personnel and to help improve plant reliability.

Fabricated branch connections between large bore pipes (including headers and manifolds) are often fabricated with a reinforced branch commonly in the form of a “catalogue” (standard size) fitting, such as an ‘o-let’. These are more prevalent in today’s combined cycle environment as compared to conventional units that used forged blocks or nozzles rather than welded-on, integrally reinforced pipe fittings. The fittings are typically thicker than the pipes in which they are installed to provide compensating reinforcement for the piping run penetration. Full reinforcement is often not achieved as the current Code requirements place all of the reinforcement on the branch side of the weld joint. As a result, higher sustained stresses are generated and, particularly in the case of creep strength enhanced ferritic (CSEF) steels, early formation creep cracking in the weld heat-affected zone (HAZ) can occur (known as Type IV damage – see Figure 1). The well documented challenges of incorrect heat treatment of the o-let weld can also add to the likelihood of damage in CSEF components. Damage is therefore most likely to occur in fabricated branches that operate with temperatures in the creep range.

News & Views, Volume 49 | Attemperator Monitoring with Wireless Sensors: Risk and Cost Reduction in Real Time

April 20, 2021/in Ben Ruchte, Combined Cycle, Fossil Power, Heat Recovery Steam Generator (HRSG), Jason Van Velsor, Matt Freeman, Monitoring, News and Views/by Structural Integrity

By: Jason Van Velsor, Matt Freeman and Ben Ruchte

Installed sensors and continuous online monitoring are revolutionizing how power plants manage assets and risk by facilitating the transformation to condition-based maintenance routines. With access to near real-time data, condition assessments, and operating trends, operators have the opportunity to safely and intelligently reduce operations and maintenance costs and outage durations, maximize component lifecycles and uptime, and improve overall operating efficiency.

But not all data is created equal and determining what to monitor, where to monitor, selecting appropriate sensors, and determining data frequency are all critical decisions that impact data value. Furthermore, sensor procurement, installation services, data historian/storage, and data analysis are often provided by separate entities, which can lead to implementation challenges and disruptions to efficient data flow.

News & View, Volume 48 | Bypass Line Spray Issues

News & Views, Volume 48 | Bypass Line Spray Issues

September 30, 2020/in Ben Ruchte, Combined Cycle, Fossil Power, Kane Riggenbach, News and Views/by Structural Integrity

By: Ben Ruchte and Kane Riggenbach

To provide operating flexibility, combined cycle plants are typically equipped with bypass systems (high pressure routing steam to cold reheat and hot reheat routing steam to the condenser). These bypass systems include conditioning valves designed to reduce steam pressures followed by outlet desuperheaters which inject water to reduce steam temperatures.

This service environment exposes the downstream piping to a high frequency of temperature transients making these areas one of the most prominent ‘industry issues’.

Structural Integrity Associates Announces the Appointment of Steve Gressler as Vice President, Fossil

April 23, 2020/in Company News, Fossil Power/by Structural Integrity

Structural Integrity Associates, Inc. (SI), a leader in engineering and technology in the power and oil & gas industries, today announced the appointment of Steve Gressler as Vice President of its Fossil business. Gressler will report to Mark Marano, SI President and Chief Executive Officer.

Mr. Gressler is a metallurgical engineer with over 30 years of experience in metallurgy, failure analysis, and the damage assessment of fossil power generation equipment and distributed heating and cooling systems with an emphasis on piping, boilers, headers, and balance of plant equipment. He is a principal contributor to engineering life cycle programs and procedures, risk assessments, analysis tools, and technologies to assess service degradation in low alloy and creep-strength enhanced ferritic steels. His current work focuses on the development, integration, and deployment of nondestructive testing and damage tracking technology in addition to engineering consulting and materials assessments.

Since joining Structural Integrity Associates in 1997, Steve has been a principal contributor to the methodologies applied for life assessment of high temperature and critical piping components. This includes characterization of creep and fatigue damage in longitudinal seam welds, girth welds, and header ligaments. It also extends to the engineering of data management systems used for aiding decision-making processes.

Marano noted, “Steve brings metallurgical leadership and technology development experience to the SI leadership team and is an integral part of our new customer focused strategy. Steve’s knowledge of the fossil business, tenure with SI, and relationships with our clients will accelerate our journey to create value for power and oil industry customers as a highly valued engineering and technology partner.”

Gressler received a Bachelor of Science in Metallurgical Engineering from the University of Pittsburgh and is a Registered Professional Engineer. Steve is also a prior recipient of the SI Riccardella Innovation Award for Prioritization Method for Fossil Plant Piping.

News & View, Volume 47 | Surface Preparation – A Pivotal Step in the Inspection Process

March 3, 2020/in Ben Ruchte, Clark McDonald, Combined Cycle, Fossil Power, Heat Recovery Steam Generator (HRSG), Materials Lab, Materials Laboratory, News and Views, Non-Destructive Evaluation, Steve Gressler/by Structural Integrity

By: Ben Ruchte, Steve Gressler, and Clark McDonald

Properly inspecting plant piping and components for service damage is an integral part of proper asset management. High energy systems constructed in accordance with ASME codes require appropriate inspections that are based on established industry practices, such as implementation of complimentary and non-destructive examination (NDE) methods that are best suited for detecting the types of damage expected within the system. In any instance where NDE is used to target service damage, it is desirable to perform high quality inspections while at the same time optimizing inspection efficiency in light of the need to return the unit to service. This concept is universally applicable to high energy piping, tubing, headers, valves, turbines, and various other power and industrial systems and components.

News & Views, Volume 47 | Metallurgical Lab Case Study: Corrosion Fatigue in WaterWall Tubes Increasingly A Safety Concern as Coal Plants Cycle

March 3, 2020/in Ben Ruchte, Fossil Power, Materials Lab, Materials Laboratory, News and Views/by Structural Integrity

By: Ben Ruchte

It is well known that conventional coal-fired utility boilers are cycling more today than they ever have. As these units have shifted to more of an ‘on-call’ demand they experience many more cycles (start-ups and shutdowns, and/or significant load swings) making other damage mechanisms such as fatigue or other related mechanisms a concern.

The most recent short-term energy outlook provided by the U.S. Energy Information Administration (EIA) indicates the share of electricity generation from coal will average 25% in 2019 and 23% in 2020, down from 27% in 2018. While the industry shifts towards new construction of flexible operating units, some of the safety issues that have been prevalent in the past are fading from memory. The inherent risks of aging seam-welded failures and waterwall tube cold-side corrosion fatigue failures are a case in point. It is well known that conventional coal-fired utility boilers are cycling more today than they ever have. As these units have shifted to more of an ‘on-call’ demand they experience many more cycles (start-ups and shutdowns, and/or significant load swings) making other damage mechanisms such as fatigue or other related mechanisms a concern. The following case study highlights this point by investigating a cold-side waterwall failure that experienced Corrosion Fatigue. While this failure did not lead to any injuries, it must be stressed that the potential for injuries is significant if the failure occurs on the cold-side of the tubes (towards the furnace wall).