Using Risk Based Maintenance Optimization RBMO to Save Costs

Maintenance is a crucial pillar in plant integrity and availability. Saving money in maintenance should be established without affecting the asset's integrity. Based on this, the core of work is to maximize the maintenance return on investment (ROI). Maintenance ROI is the ratio between invested money in maintenance to mitigated risks due to maintenance actions. The objective is to minimize maintenance cost while maximizing assets integrity and availability. RBMO starts with ‘Maintenance Criticality Assessment’ (MCA) at unit/system level to define high (20 % of systems that represent 80% of risks), medium (20% of systems that represent 15% of risks), and low critical systems (60% of systems that represent only 5% of risks). Based on system criticality, a dedicated risk assessment is implemented to evaluate risks at tag level to define the worst maintenance action/s. High critical systems’ maintenance programs are developed using ‘Reliability-Centered Maintenance’ (RCM). Medium critical system maintenance program is developed using ‘Failure Mode, Effects and criticality analysis’ (FMECA). "Maintenance strategy for Low Critical item" guideline document is developed to define the best maintenance strategy for low critical units. All risks are evaluated using the standard ADNOC risk matrix. The risk is converted to monetary value in $ to evaluate maintenance actions using a formula. A special program was developed to facilitate MCA evaluation for each system and represent risk as monetary value using ADNOC Risk Matrix taking into consideration the redundancy and demand on a system during operation. MCAs were completed for all ADNOC Onshore Assets, see results below. Optimization starts by evaluating maintenance programs for low critical systems to save costs where low critical systems represent 50% to 60% of total systems in ADNOC Onshore. Based on this the total number of work orders has decreased by 6856, which is equivalent to saving $1M annually. In parallel, RCMs are conducted on high critical systems. Risk mitigation calculator in $ value was developed and embedded in the RCM information sheet to calculate cost benefit from implementing maintenance programs that were developed. RBMO is a systematic and traceable methodology to minimize maintenance cost and at the same time maximize system integrity and availability. This work showed the importance of reviewing the low critical systems’ maintenance program, as a first step in RBMO after implementing MCA, where low critical systems represent 50% to 60% of total assets and only 5% of total risks. ADNOC Onshore developed a dedicated guideline document "Maintenance Strategy for Low Critical Item" to facilitate decision making for proper maintenance strategy for low critical systems. Adding RCM risk mitigation calculator to RCM to calculate RCM cost benefit.

Service Exchange or Major Overhaul. Which Philosophy to Implement for Gas Turbine

Maintenance costs and machine availability are two of the most important concerns to gas turbine equipment owner. Therefore, a well thought out maintenance program that reduces costs while increasing equipment availability should be instituted. The correct implementation of planned maintenance relying on preventive maintenance optimization through perfect inspection frequency and scope provides direct benefits in the avoidance of forced outages, unscheduled repairs, and downtime. Major overhaul is carried out for each gas turbine every 48,000 firing hours which costs around 1 M USD for each engine and with more than 8 months unavailability for the unit. To increase equipment availability and enhance cost and time efficiency, alternatives approaches were evaluated including Service Exchange of gas turbines. It is found that service exchange is the best option for optimizing time and cost of overhaul of such engines. This paper is written to improve Major Overhaul practice for existing Gas Turbines from ongoing practice of routine major overhaul including engine strip down, inspection and repair to Service Exchange of Gas Generator and Power Turbine every 48,000 firing hours.

Corrosion Mitigation Using Nonmetallic Piping for In-Plant Hydrocarbon Service

The underground hydrocarbon metallic lines are usually subjected to severe corrosion due to several reasons such as high water table in the area and due to intermittent bi-directional crude service or similar environmental factors. To meet the challenge, non-metallic underground crude transfer lines may be considered to carry oil from/to the bulk storage sites. Since there are not many non-metallic applications in HC services, it may become a challenge to get the necessary approvals from the various stake holders in terms of concerns for asset integrity and the costs. This report details the conversion of metallic crude pipeline application to a non-metallic one. Normally, the in-kind replacement will involve an internally coated CS line to reduce corrosion rate. However, engineering studies and assessments reveal that there are greater economic benefits when adapting to a non-metallic counterpart. For a generic case, hydraulics on a 1.7km crude transfer line with 48" diameter and the intermittent crude service revealed that 36" non-metallic version could do the job with less installation costs as minimal site activities will be required and there will be no requirements of non-destructive tests (NDT). Only a service test following the installation may be necessary to prove the operational integrity. Cost comparisons showed a 28% less project cost in using the non-metallic pipeline while meeting all other application requirements. The introduction of non-metallic line would take away the problem of the external and internal corrosion from the equation. Especially in the aging facilities where fatigue becomes an issue, the carbon steel line always requires additional maintenance activities and there was always a chance to develop an underground pin hole. Therefore, an extensive inspection program had its own costs to maintain the line. With the non-metallic pipe usage, not only the construction costs can be lowered but it could avoid major inspection and maintenance program costs. The Nonmetallic line is considered low to maintenance free, and additional long-term savings are expected. This application opens the door for the utilization of nonmetallic material in plant hydrocarbon processes. And given the size considered of this line (36 inches), this allows for further consideration to install nonmetallic piping on a wide range of applications. Also, non-metallics are especially effective for sluggish or intermittent flows and areas with high water table to avoid all sorts of erosion and corrosion issues internally due to process conditions or externally due to environmental conditions.

Detraining Slows and Maintenance Training Over 6 Years Halts Parkinsonian Symptoms-Progression

Introduction: There are scant data to demonstrate that the long-term non-pharmaceutical interventions can slow the progression of motor and non-motor symptoms and lower drug dose in Parkinson's disease (PD).Methods: After randomization, the Exercise-only (E, n = 19) group completed an initial 3-week-long, 15-session supervised, high-intensity sensorimotor agility exercise program designed to improve the postural stability. The Exercise + Maintenance (E + M, n = 22) group completed the 3-week program and continued the same program three times per week for 6 years. The no exercise and no maintenance control (C, n = 26) group continued habitual living. In each patient, 11 outcomes were measured before and after the 3-week initial exercise program and then, at 3, 6, 12, 18, 24, 36, 48, 60, and 72 months.Results: The longitudinal linear mixed effects modeling of each variable was fitted with maximum likelihood estimation and adjusted for baseline and covariates. The exercise program strongly improved the primary outcome, Motor Experiences of Daily Living, by ~7 points and all secondary outcomes [body mass index (BMI), disease and no disease-specific quality of life, depression, mobility, and standing balance]. In E group, the detraining effects lasted up to 12 months. E+M group further improved the initial exercise-induced gains up to 3 months and the gains were sustained until year 6. In C group, the symptoms worsened steadily. By year 6, levodopa (L-dopa) equivalents increased in all the groups but least in E + M group.Conclusion: A short-term, high-intensity sensorimotor agility exercise program improved the PD symptoms up to a year during detraining but the subsequent 6-year maintenance program was needed to further increase or sustain the initial improvements in the symptoms, quality of life, and drug dose.

The Application of Angulated Screw-Channels in Metal-Free, Implant-Supported Restorations: A Retrospective Survival Analysis

Angulated screw channels (ASC) allow the clinician to reposition the access hole of screw-retained restorations, improving the design of the rehabilitation and the esthetic outcome. Few clinical studies are available on the efficacy of these restorations, especially at longer follow-ups and with a large number of subjects. The objective of this study was therefore to retrospectively evaluate patients rehabilitated with screw-retained restorations using ASC. The time of delivery and their adherence to the maintenance program was obtained, as well as the characteristics of the restoration and of the patient’s occlusion; a Kaplan–Meier survival curve was then built to investigate the success rate of these restorations and the effects of several variables were evaluated with a Cox model. A total of 105 subjects and 162 implants were enrolled in this study; after 42 months a success rate (92%) similar to what is reported for conventional screw-retained restorations was encountered. Monolithic zirconia restorations (n = 52) had a higher success rate (95%) when compared to partially veneered restorations (n = 53), which suffered a higher number of complications (90%). The other variables had no statistically significant effect. Implant supported prostheses adopting ASC provide a favorable outcome both in the posterior and anterior regions and can therefore be adopted to treat cases where the implant angulation is unfavorable for a conventional screw-retained prosthesis.

Integrating acceleration signal processing and image segmentation for condition assessment of asphalt roads

A proactive road maintenance system enables agencies to better allocate resources to manage their road networks. An inventory of the roads’ conditions is an essential component of such maintenance program. This research project proposes a hybrid system to asses the condition of the asphalt roads, which uses a dashboard-mounted smartphone to simultaneously collect the acceleration response of a vehicle and the video footage of the road surface while driving. The system analyzes acceleration data for anomalous events that could indicate a defect. Then the computer vision module of the system applies semantic segmentation in the corresponding frame to the detected anomaly to identify defects. This system demonstrated 84% recall and 88% precision rates in detection of anomalies in two road segments. Despite these promising results, the system can only detect the defects that are passed over and it could miss some defects with small acceleration responses, such as traverse cracks.

Leaks, Pipe Breaks, and Preventive Maintenance

A better understanding of leak related effects has implications for pipe rehabilitation, system economics, customer disruption, and environmental sustainability. Reducing leakage be a result of a well-suited preventive maintenance program. The purpose of this study is to inspect approximately 10% of the runouts (branch pipes) between the plumbing fixtures and the risers to estimate the extent of serious corrosion of the runouts that may cause leaks in the future. For collecting the site data for our study, we visited the building and investigated piping through 57 different access openings in 31 randomly selected apartments. These apartments were selected to allow observation of a variety of risers at varying elevations. We observed in about 20% of the runouts inspected, the remaining thickness of the steel pipe was less than 60% in the areas that we could access. The runouts are in danger of developing leaks. Because of the high potential cost of leaks and the possibility of that 20%, or 120 pipes, could leak soon, recommend replacement of all the runouts. System performance can only be reliably characterized through monitoring and analysis of relevant data. Performance monitoring is concerned with measuring system efficiency and to what extent the system is delivering the parameters what it was designed for (i.e., flow, pressure, energy, water quality, etc.).

Evaluation of fire safety maintenance of an educational laboratory facility

This paper aims to evaluate fire safety systems of educational building laboratories by exploring the passive, active systems, and fire safety management. The evaluation was carried out in the University Integrated Engineering Lab in Depok City based on the applicable standards and regulations in Indonesia. Educational laboratories require a high-level safety measure against potential fire hazards due to the nature of the activities and equipment used. A reliable fire protection system and fire safety maintenance program are required to provide a comprehensive safety working environment. Lack of maintenance of fire safety systems is one of the causes of fires in educational laboratories. Triangulation methods consisting of field observation, interview, and document review were applied in this study along with descriptive and comparative analysis. Measurements by means of AutoCAD and Dialux simulation were carried out to support the evaluation process. The results show that the main features of the fire safety systems are installed in these laboratories according to the applicable standards and regulations. However, this study reveals that it is necessary to repair the walls, rearrange the sprinkler’s head spacing, add fire extinguisher, sort waste, and establish a fire emergency response team and safety organization.

Excessive fetal growth affects HSC quiescence maintenance through epigenetic programming of EGR1 transcriptional network

Fetal development is a critical period to shape stem cell identity and functions. Detrimental environments during this period are associated with epigenetics alteration of hematopoietic stem and progenitor cells (HSPC) with unknown functional impacts. We implemented a single-cell resolution integrative analysis combining epigenomics, transcriptomics, and functional data to elucidate the epigenetic influence associated with excessive fetal growth on HSPCs. We showed that hematopoietic stem cells (HSC) from large for gestational age neonates present a coordinated DNA hypermethylation and decrease expression for genes of the EGR1 transcriptional network including SOCS3, KLF2, and JUNB known to sustain stem cell quiescence and pluripotency. Furthermore, these changes were associated with a decreased ability for HSCs to stay undifferentiated and a decreased ability to expand in response to stimulation. Taken together, these results show that fetal overgrowth affects hematopoietic stem cells quiescence maintenance program through an epigenetic programming of the EGR1 related transcriptional network.