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Statement of Work. Y-12 National Security Complex Security Infrastructure Revitalization Program Project - Combination Inspector

Fox, Lora; Powledge, Laura

The Y-12 SIRP Quadrant 1, Quadrant 2, and Vehicle Barrier project involves the following summary elements. The perimeter intrusion detection and assessment system (PIDAS) is an existing system at the Y-12 National Security Complex, which is a government-owned facility located in Oak Ridge, Tennessee, and managed by Consolidated Nuclear Security, LLC (CNS) for the Department of Energy (DOE). National Technology and Engineering Solutions of Sandia, LLC (NTESS) is the engineering design agent and construction manager (CM) for the Y-12 SIRP effort. The Quadrants 1 and 2 portion of the project involves the replacement of the PIDAS, and the vehicle barrier portion of the project involves the installation of a continuous passive vehicle barrier alongside the inner PIDAS fence.

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TYPE Other Report YEAR 2021
DOIDOIOSTIOSTI

Ultra-Wide-Bandgap Semiconductors: Challenges and Opportunities (invited)

Kaplar, Robert J.; Allerman, Andrew A.; Armstrong, Andrew A.; Crawford, Mary H.; Pickrell, Gregory W.; Dickerson, Jeramy; Flicker, Jack D.; Neely, Jason C.; Paisley, Elizabeth; Baca, Albert; Klein, Brianna A.; Douglas, Erica A.; Reza, Shahed; Binder, Andrew T.; Yates, Luke; Slobodyan, Oleksiy; Sharps, Paul; Simmons, Jerry; Tsao, Jeffrey Y.; Hollis, Mark; Johnson, Noble; Jones, Ken; Pavlidis, Dimitris; Goretta, Ken; Nemanich, Bob; Goodnick, Steve; Chowdhury, Srabanti

Abstract not provided.

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TYPE Presentation YEAR 2021
OSTI

Performance Evaluation of Comparative Vacuum Monitoring and Piezoelectric Sensors for Structural Health Monitoring of Rotorcraft Components

Roach, Dennis P.

The costs associated with the increasing maintenance and surveillance needs of aging structures are rising at an unexpected rate. Multi-site fatigue damage, hidden cracks in hard-to-reach locations, disbonded joints, erosion, impact, and corrosion are among the major flaws encountered in today’s extensive fleet of aging aircraft and space vehicles. Aircraft maintenance and repairs represent about a quarter of a commercial fleet’s operating costs. The application of Structural Health Monitoring (SHM) systems using distributed sensor networks can reduce these costs by facilitating rapid and global assessments of structural integrity. The use of in-situ sensors for real-time health monitoring can overcome inspection impediments stemming from accessibility limitations, complex geometries, and the location and depth of hidden damage. Reliable, structural health monitoring systems can automatically process data, assess structural condition, and signal the need for human intervention. The ease of monitoring an entire on-board network of distributed sensors means that structural health assessments can occur more often, allowing operators to be even more vigilant with respect to flaw onset. SHM systems also allow for condition-based maintenance practices to be substituted for the current time-based or cycle-based maintenance approach thus optimizing maintenance labor. The Federal Aviation Administration has conducted a series of SHM validation and certification programs intended to comprehensively support the evolution and adoption of SHM practices into routine aircraft maintenance practices. This report presents one of those programs involving a Sandia Labs-aviation industry effort to move SHM into routine use for aircraft maintenance. The Airworthiness Assurance NDI Validation Center (AANC) at Sandia Labs, in conjunction with Sikorsky, Structural Monitoring Systems Ltd., Anodyne Electronics Manufacturing Corp., Acellent Technologies Inc., and the Federal Aviation Administration (FAA) carried out a trial validation and certification program to evaluate Comparative Vacuum Monitoring (CVM) and Piezoelectric Transducers (PZT) as a structural health monitoring solution to specific rotorcraft applications. Validation tasks were designed to address the SHM equipment, the health monitoring task, the resolution required, the sensor interrogation procedures, the conditions under which the monitoring will occur, the potential inspector population, adoption of CVM and PZT systems into rotorcraft maintenance programs and the document revisions necessary to allow for their routine use as an alternate means of performing periodic structural inspections. This program addressed formal SHM technology validation and certification issues so that the full spectrum of concerns, including design, deployment, performance and certification were appropriately considered. Sandia Labs designed, implemented, and analyzed the results from a focused and statistically relevant experimental effort to quantify the reliability of a CVM system applied to Sikorsky S-92 fuselage frame application and a PZT system applied to an S-92 main gearbox mount beam application. The applications included both local and global damage detection assessments. All factors that affect SHM sensitivity were included in this program: flaw size, shape, orientation and location relative to the sensors, as well as operational and environmental variables. Statistical methods were applied to performance data to derive Probability of Detection (POD) values for SHM sensors in a manner that agrees with current nondestructive inspection (NDI) validation requirements and is acceptable to both the aviation industry and regulatory bodies. The validation work completed in this program demonstrated the ability of both CVM and PZT SHM systems to detect cracks in rotorcraft components. It proved the ability to use final system response parameters to provide a Green Light/Red Light (“GO” – “NO GO”) decision on the presence of damage. In additional to quantifying the performance of each SHM system for the trial applications on the S-92 platform, this study also identified specific methods that can be used to optimize damage detection, guidance on deployment scenarios that can affect performance and considerations that must be made to properly apply CVM and PZT sensors. These results support the main goal of safely integrating SHM sensors into rotorcraft maintenance programs. Additional benefits from deploying rotorcraft Health and Usage Monitoring Systems (HUMS) may be realized when structural assessment data, collected by an SHM system, is also used to detect structural damage to compliment the operational environment monitoring. The use of in-situ sensors for health monitoring of rotorcraft structures can be a viable option for both flaw detection and maintenance planning activities. This formal SHM validation will allow aircraft manufacturers and airlines to confidently make informed decisions about the proper utilization of CVM and PZT technology. It will also streamline future regulatory actions and formal certification measures needed to assure the safe application of SHM solutions.

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TYPE SAND Report YEAR 2021
DOIDOIOSTIOSTI

Rapid Quality Assessment in Additive Manufacturing: New Procedure Accelerates Build Quality Assessment. White paper

Pegues, Jonathan W.; Shamsaei, Nima; Carrion, Patricio

Accelerated growth of the additive manufacturing (AM) industry in recent years is accompanied by a rising need for methods to quickly assess quality at-scale. Current practices for quality inspection include nondestructive test methods and destructive testing of witness coupons, which are artifacts built alongside the actual part. However, these methods can be costly and time-consuming. Recognizing this need, the Additive Manufacturing Center of Excellence (AM CoE) initiated a project led by its partner, Auburn University, to develop rapid testing procedure using asbuilt samples tested in torsion to quantitatively assess build quality. The presented work developed a rapid testing procedure using as-built samples tested in torsion to quantify small variances for assessing build quality.

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TYPE Other Report YEAR 2021
DOIOSTIDOIOSTI
Results 12951–13000 of 100,993
Results 12951–13000 of 100,993
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