Corrosion of Stainless Steel Pipes Buried in the Soils of Seoul Metropolitan During One Year

Background: Retention is an integral phase in which teeth are maintained in their newly adapted position for which retainers are inserted. Retainers are generally of two types: removable and fixed. Fixed retainers are indicated in the mandibular arch for an indefinite period specifically in the non-extraction cases. Changes in intercanine and intermolar widths are valuable parameters to evaluate the stability. The objectives of this study were to assess and compare the mandibular intercanine and intermolar width changes following orthodontic treatment after insertion of two types of fixed lingual retainers for one year. Methods: Total 54 subjects were recruited in which two types of fixed lingual retainers were inserted in the mandibular arch randomly. Intercanine and intermolar arch widths were measured by digital caliper of 0.01 mm accuracy. Data was analyzed by using Statistical Package of Social Sciences (SPSS V-21). Chi-square and independent t tests were used to compare baseline characteristics. Intercanine and intermolar widths were assessed and compared using independent t test, p-value ≤ 0.05 is considered as statistically significant. Results: Intercanine width increased from baseline to T4 in both retainers. When mean differences of intercanine width were compared between two retainers significant differences were observed at T1, T2, T3 and T4 with significant p-values (< 0.05) and increased intercanine width with multistranded stainless steel wire (MSW) retainers. Conclusion: Mandibular intercanine width increases significantly in post retention phase with multistranded stainless steel retainers. Thus, fiber reinforced composite retainers are more effective in preserving the arch width changes.

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Non-Metallic Technology Deployment for the Next Generation of ADNOC Production Facilities

10.2118/207830-ms ◽

2021 ◽

Author(s):

Raymond Nicholas Burke ◽

Abdallah Mohd AR Al Tamimi ◽

Wael Salem Al Shouly ◽

Mohamed Ali Jaber ◽

David Erik Baetsen

Keyword(s):

Group Technology ◽

Steering Committee ◽

Thermoplastic Composite ◽

Gas Field ◽

Steel Pipes ◽

Pilot Trials ◽

Integrity Management ◽

One Year ◽

Corrosion Of Steel ◽

Duration Of Operation

Abstract Industry-wide, the degradation and corrosion of steel infrastructure and the associated maintenance to prevent or mitigate this, poses a heavy environmental and operational burden across many industry segments. To address these challenges, ADNOC Group Technology, led by our Non-Metallic Steering Committee and ADNOC Upstream, in partnership with several selected specialist product companies, is deploying a range of innovative solutions as pilot trials within a holistic R&D program – which is aiming to transform our production and processing facilities, with a close focus on integrity management – and specifically we are assessing the deployment of non-metallic pipelines, storage and process vessels as well as downhole tubing and casing. Focusing specifically on flowlines and pipelines - traditional steel pipes used in the oil patch are burdensome to store, transport and install, as well as susceptible to degradation, corrosion-driven wall loss in challenging operational environments, such as those found Onshore and Offshore Abu Dhabi. This vulnerability results in increased operating risks as facilities mature, adding cost and time for inspection, maintenance and eventually - replacements that will lead to production deferrals or interruptions. A range of non-metallic pipeline technologies are being assessed and piloted in this program, including stand-alone extruded polymeric pipe and liners, Reinforced Thermoplastic Pipe (RTP) used Onshore and Offshore, specialized non-metallic flexible pipelines for Offshore including Thermoplastic Composite Pipe (TCP) and downhole tubulars. The methodology involves placing segments of RTP into live pipeline systems for a finite duration of operation – usually one year – and then removing sections to assess any degradation in performance, or capability of the RTP during that time. These test results will be the subject of a further publication at the end of this trial period. In this paper, we will focus on RTP piloting Onshore and specifically mention a unique trial in an ultra-sour gas field, where the technology has already delivered the required performance: safely transporting gas with levels of H2S up to 10% by volume. This trial also proves that specifically engineered non-metallic products may be successfully operated at the high temperature and high pressure (HPHT) levels that are characteristic of our reservoirs.

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Elastic-Plastic Fracture Mechanics Analysis of Cast Stainless Steel Pipes (Influence of Axial Load on Z-Factor of Pipes With Circumferential Crack Under Bending Load)

Volume 1A: Codes and Standards ◽

10.1115/pvp2013-98154 ◽

2013 ◽

Author(s):

Masayuki Kamaya ◽

Kiminobu Hojo

Keyword(s):

Stainless Steel ◽

Axial Load ◽

Power Plants ◽

Structural Integrity ◽

Term Operation ◽

Steel Pipes ◽

Integrity Assessment ◽

Plastic Failure ◽

Elastic Plastic ◽

Bending Load

Since the ductility of cast austenitic stainless steel pipes decreases due to thermal aging embrittlement after long term operation, not only plastic collapse failure but also unstable ductile crack propagation (elastic-plastic failure) should be taken into account for the structural integrity assessment of cracked pipes. In the ASME Section XI, the load multiplier (Z-factor) is used to derive the elastic-plastic failure of the cracked components. The Z-factor of cracked pipes under bending load has been obtained without considering the axial load. In this study, the influence of the axial load on Z-factor was quantified through elastic-plastic failure analyses under various conditions. It was concluded that the axial load increased the Z-factor; however, the magnitude of the increase was not significant, particularly for the main coolant pipes of PWR nuclear power plants.

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Ultrasonic Measurement of Hoop Residual Stress in Stainless Steel Pipes

Manufacturing and Industrial Engineering ◽

10.12776/mie.v12i1-2.175 ◽

2013 ◽

Vol 12 (1-2) ◽

Cited By ~ 1

Author(s):

Yashar Javadi

Keyword(s):

Residual Stress ◽

Stainless Steel ◽

Ultrasonic Measurement ◽

Steel Pipes

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Efficiency and safety of using a peritoneal dialysis catheter weighted with a stainless steel ballast : the Limousin experience

Bulletin de la Dialyse à Domicile ◽

10.25796/bdd.v2i4.23873 ◽

2019 ◽

Vol 2 (4) ◽

pp. 193-200

Author(s):

Bénédicte Larivière-Durgueil ◽

Rémi Boudet ◽

Marie Essig ◽

Stéphane Bouvier ◽

Ali Abdeh ◽

...

Keyword(s):

Stainless Steel ◽

Peritoneal Dialysis ◽

Infectious Complications ◽

Control Group ◽

Peritoneal Dialysis Catheter ◽

Causal Factors ◽

Catheter Migration ◽

Mechanical Complications ◽

Increased Risk ◽

One Year

Objective: To assess the recurrence of PD catheter migration after the introduction of a walnut ballast. Materials and Methods: Retrospective study from 1999 to 2014 of PD patients followed in Limousin. Were compared two groups: ballast group (patients who benefited from the establishment of stainless steel ballast at the intraperitoneal catheter extremity) with 26 patients and control group with 204 patients. The primary endpoint was the occurrence of an episode catheter’s migration after ballast’s establishment. Secondary objectives were (i) to determine the causal factors leading to the catheter weighting, (ii) to ensure the safety of the procedure on the following criteria: infectious complications, mechanicals complications, epurations criteria, and catheter’s survival. Results: More than one year after the implementation of the ballast, no recurrent migration was observed in 86.6% of cases. It wasn’t found an increased risk of infections (OR = 0.5, 95% CI [0.22, 1.13]) or mechanical complications (OR = 1.77- 95% CI [0.77, 4.05]) between the two groups. The adequation criteria were similar: KT / V total : 2.37 in the control group and 2.28 in the ballast group (p = 0.63). The survival of the ballast catheter was comparable among the two groups (p = 0.983). Three causal factors that led to the ballast were identified: automated peritoneal dialysis (APD) (OR = 0.38, 95% CI [0.16, 0.9]), the failure from the first use of the catheter (OR = 19.48, CI 95 % [7.67, 49.48]) and the incarceration of the omentum (OR = 15.84, 95% CI [5.81, 43.21]). Conclusion: The ballast used in these study appears to prevent recurrence of migration, without any impact in terms of infectious or mechanical complications, or on the dialysis criteria or on catheter’s survival. However this catheter does currently not have an EC authorization

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