A Study of the Reproducibility and Diversity of the Supply Chain in Manufacturing Hot Isostatically Pressed Type 316L Stainless Steel Components for the Civil Nuclear Sector

2020 ◽  
Vol 6 (2) ◽  
Author(s):  
William Kyffin ◽  
David Gandy ◽  
Barry Burdett
Keyword(s):  
Stainless Steel ◽  
Supply Chain ◽  
Material Properties ◽  
Service Providers ◽  
Full Range ◽  
Hold Time ◽  
Process Window ◽  
Low Oxygen ◽  
Test Program ◽  
Significant Difference

Abstract Hot isostatic pressing (HIP) of type 316 L stainless steel powder has been an established manufacturing practice for more than 25 years in the oil and gas sector and more recently in the naval defense sector. To demonstrate the capability of the powder metallurgy HIP (PM/HIP) for nuclear power applications, a systematic study of 316 L commercial powder production, encapsulation/consolidation providers, and selected HIP parameters was undertaken by the Nuclear AMRC in collaboration with the Electric Power Research Institute (EPRI). In this study, the 316 L powder specification limited the oxygen content of the powder to under 130 parts per million (ppm), which reflects the improvements that commercial powder suppliers have been making over the past decade to ensure greater powder cleanliness. The test program assessed powder supply, HIP service provider, and HIP sustain time. Excellent test results were achieved across the full range of variables studied with all billets meeting the specification requirements of ASTM A988 and additional requirements imposed based on nuclear manufacturing standards. Significantly, the study demonstrated the robustness of the PM/HIP supply chain, as material produced via differing HIP service providers resulted in very consistent material properties across the destructive test program. Furthermore, no significant difference in material properties was noted for material HIP between 2 and 8 h hold time, suggesting that the HIP process window is large. Both these results are significant from an end-user standpoint as they highlight the uniformity of the process through the full manufacturing cycle from powder procurement to destructive testing. Despite all material passing specification requirements, some property variation was noted for differing powder suppliers. Considering the systematic approach, this was attributed to powder composition, with both low oxygen and high nitrogen contents contributing to improvements in Charpy impact strength and tensile strength, respectively.

A Study of the Material Properties and Performance of Hot Isostatically Pressed (HIP) Type 316L Stainless Steel Powders and HIP Processing Available From Today’s International Supply Chain

2018 ◽  
Author(s):  
William Kyffin ◽  
David Gandy ◽  
Barry Burdett
Keyword(s):  
Stainless Steel ◽  
Supply Chain ◽  
Impact Toughness ◽  
Oxygen Content ◽  
Material Properties ◽  
Hold Time ◽  
Charpy Impact ◽  
Charpy Impact Toughness ◽  
Test Programme ◽  
Type 316L

Hot Isostatic Pressing (HIP) of type 316L austenitic stainless steel powder has been an established manufacturing practice for more than twenty five years within the oil and gas sectors and more recently in the naval defence industry. The successful ASME Code Case approval (N-834) has facilitated the manufacture of 316L components via Powder Metallurgy HIP (PM/HIP) for the civil nuclear sector. However, a number of issues have tended to hinder the uptake of PM/HIP as an alternative viable manufacturing route for both castings and forgings. Firstly, the powder specification for 316L and HIP processing parameters has typically been left to the discretion of the manufacturers. As such, the finer details of HIP product specification require greater clarity and definition for optimum performance/reproducibility. Secondly, comparison of historical data for 316L PM/HIP has shown variation in the Charpy impact toughness performance. These differences have been attributed to the oxygen content of the atomised powder, with greater oxygen contents yielding product with reduced impact properties. Based on these factors, a systematic study of the current state of the art of 316L commercial powder production, encapsulation/consolidation and selected HIP parameters was undertaken in collaboration with the Electric Power Research Institute (EPRI). A 316L powder specification was developed that primarily limited the oxygen content of the powder to under 130ppm. This lower oxygen limit reflects the improvements that commercial powder suppliers have been making over the past decade to ensure greater powder cleanliness. The test programme generated a significant body of test data based on 3 × 3 × 3 matrix of: powder supply, HIP service provider and HIP sustain times. The results were excellent across the full range of variables studied with all test billets passing the specification requirements of ASTM A988 and additional imposed requirements. Very consistent 316L material properties were produced for billets manufactured via differing HIP service providers across the comprehensive destructive test programme. This demonstrates the robustness and uniformity of the PM/HIP supply chain in producing 316L material of the requisite quality. In addition, no significant difference in material properties was noted for material pressed between 2–8 hours hold time, suggesting that the HIP process window is large with respect to hold time. Of significant note was that material produced with one powder yielded material with consistently the highest strengths and Charpy impact toughness. This has been attributed to chemical composition of the powder, which featured both a low oxygen and also a high nitrogen content.

A Systematic Study of the Material Performance of Hot Isostatically Pressed Type 316L Stainless Steel Powder for the Civil Nuclear Sector

2018 ◽  
Author(s):  
William Kyffin ◽  
David Gandy ◽  
Barry Burdett
Keyword(s):  
Stainless Steel ◽  
Systematic Study ◽  
Material Properties ◽  
316L Stainless Steel ◽  
Steel Powder ◽  
Stainless Steel Powder ◽  
Test Programme ◽  
Significant Difference ◽  
Type 316L ◽  
Type 316L Stainless Steel

Hot Isostatic Pressing (HIP) of type 316L stainless steel powder has been an established manufacturing practice for more than twenty-five years in the oil and gas sector and more recently in the naval defence sector. To demonstrate the capability of the powder metallurgy HIP (PM/HIP) for nuclear power applications a systematic study of 316L commercial powder production, encapsulation/consolidation providers and selected HIP parameters was undertaken by the Nuclear AMRC in collaboration with the Electric Power Research Institute (EPRI). In the study, the 316L powder specification limited the oxygen content of the powder to under 130 parts per million (ppm), which reflects the improvements that commercial powder suppliers have been making over the past decade to ensure greater powder cleanliness. The test programme assessed powder supply, HIP service provider and HIP sustain time. Excellent test results were achieved across the full range of variables studied with all billets meeting the specification requirements of ASTM A988 and additional requirements imposed based on nuclear manufacturing standards. Significantly, the study demonstrated the robustness of the PM/HIP supply chain, as material produced via differing HIP service providers resulted in very consistent material properties across the destructive test programme. Furthermore, no significant difference in material properties were noted for material HIP’ed between 2–8 hours hold time, suggesting that the HIP process window is large. Both these results are significant from an end-user standpoint as they highlight the uniformity of the process through the full manufacturing cycle from powder procurement to destructive testing. Despite all material passing specification requirements, some property variation was noted for differing powder suppliers. Considering the systematic approach, this was attributed to powder composition, with both low oxygen and high nitrogen contents contributing to improvements in Charpy impact strength and tensile strength respectively.

Precision and bias in quantitative EDS: ASTM results

1992 ◽  
Vol 50 (2) ◽  
pp. 1654-1655
Author(s):  
John J. Friel
Keyword(s):  
Stainless Steel ◽  
Quantitative Analysis ◽  
Mechanical Alloy ◽  
Dead Time ◽  
Test Program ◽  
Round Robin Test ◽  
Wide Range ◽  
American Society ◽  
Takeoff Angle ◽  
Standardless Analysis

Committee E-04 on Metallography of the American Society for Testing and Materials (ASTM) conducted an interlaboratory round robin test program on quantitative energy dispersive spectroscopy (EDS). The test program was designed to produce data on which to base a precision and bias statement for quantitative analysis by EDS. Nine laboratories were sent specimens of two well characterized materials, a type 308 stainless steel, and a complex mechanical alloy from Inco Alloys International, Inconel® MA 6000. The stainless steel was chosen as an example of a straightforward analysis with no special problems. The mechanical alloy was selected because elements were present in a wide range of concentrations; K, L, and M lines were involved; and Ta was severely overlapped with W. The test aimed to establish limits of precision that could be routinely achieved by capable laboratories operating under real world conditions. The participants were first allowed to use their own best procedures, but later were instructed to repeat the analysis using specified conditions: 20 kV accelerating voltage, 200s live time, ∼25% dead time and ∼40° takeoff angle. They were also asked to run a standardless analysis.

scholarly journals Comparative Evaluation of Fracture Resistance of Endodontically Treated Teeth Restored with Resin Fiber Post and Stainless Steel Post: An In Vitro Study

2015 ◽  
Vol 03 (02) ◽  
pp. 080-084
Author(s):  
Vijay Singh ◽  
Poonam Bogra ◽  
Saurabh Gupta ◽  
Navneet Kukreja ◽  
Neha Gupta
Keyword(s):  
Stainless Steel ◽  
Fracture Resistance ◽  
Testing Machine ◽  
Compressive Force ◽  
Control Group ◽  
Fiber Post ◽  
Endodontically Treated Teeth ◽  
Group I ◽  
Significant Difference

AbstractFracture resistance of endodontically treated teeth restored with post. Aims: This study aims to compare the fracture resistance of endodontically treated teeth restored with resin fiber and stainless steel post. Commercially available prefabricated resin fiber post(Dentsply Maillefer Easy Post), prefabricated stainless steel post(Coltene/Whaledent Parapost) were used. Methods and Material: Forty five maxillary central incisors were obturated and divided into 3 groups: Control Group (Group I) without any post (n = 15), Resin Fiber Post Group (Group II) (n = 15) and Stainless Steel Post Group (Group III) (n = 15). In all Groups except control group, post space was prepared; a post was cemented, and a core build-up was provided. All the specimens were subjected to compressive force under a universal testing machine until fracture. Statistical analysis used: The results were analyzed using the variable analysis test (ANOVA). Results: One-way analysis of variance revealed significant difference among test groups. The control group demonstrated highest fracture resistance (925.2183 N), followed by the resin fiber post group (486.7265 N) and stainless steel post group (423.539N). Conclusions: Teeth restored with resin fiber post showed higher fracture resistance values than prefabricated stainless steel post.

scholarly journals An Exploration of the Critical Risk Factors in Sustainable Telecom Services: An Analysis of Indian Telecom Industries

2021 ◽  
Vol 13 (2) ◽  
pp. 445
Author(s):  
Wen-Kuo Chen ◽  
Venkateswarlu Nalluri ◽  
Suresh Ma ◽  
Mei-Min Lin ◽  
Ching-Torng Lin
Keyword(s):  
Risk Factors ◽  
Supply Chain ◽  
Supply Chain Management ◽  
Service Providers ◽  
Telecommunications Industry ◽  
Sustainable Supply Chain ◽  
Chain Management ◽  
Sustainable Supply Chain Management ◽  
The Impact ◽  
The Relationship

Different sources of risk factors can occur in sustainable supply chain management due to its complex nature. The telecommunication service firm cannot implement multiple improvement practices altogether to overcome the risk factors with limited resources. The industries should evaluate the relationship between risk factors and explore the determinants of improvement measures. The purpose of the present study is to identify and analyze critical risk factors (CRFs) for enhancing sustainable supply chain management practices in the Indian telecommunication industry using interpretive structural modelling (ISM). Risk factors are identified through a literature survey, and then with the help of experts, nine CRFs are identified using a fuzzy Delphi method (FDM). The relationship among these CRFs has been analyzed using ISM, and the driving and the dependence power of those CRFs are analyzed. Results indicate that both “government policies (laws and regulations)” and “the impact of rapid change in technology” are independent or key factors that affect the sustainability of the telecommunications supply chain. In addition, results provide significant managerial implications, including enhanced sustainability, and the government should build justice, fairness, open laws, certainties, and regulations to prevent risk in the telecommunications industry supply chain; service providers should monitor the rapidly evolving technologies and focus on technical learning and organizational capacity development to overcome the impact of technological changes. The contribution of this study is using a novel approach to establish a hierarchical structural model for an effective understanding of CRFs relationships and to explore decisive risk factors that can help telecom service providers to better plan and design effective improvement strategies to enhance sustainability supply chain management.

scholarly journals Modeling logistics service providers in a non-cooperative supply chain

2016 ◽  
Vol 40 (13-14) ◽  
pp. 6340-6358 ◽  
Author(s):  
Ernesto D.R. Santibanez-Gonzalez ◽  
Ali Diabat
Keyword(s):  
Supply Chain ◽  
Service Providers ◽  
Logistics Service ◽  
Logistics Service Providers

Bending Properties of General Purpose Stainless Steel Wire Formed for Orthodontic Use

2013 ◽  
Vol 746 ◽  
pp. 394-399
Author(s):  
Niwat Anuwongnukroh ◽  
Yosdhorn Chuankrerkkul ◽  
Surachai Dechkunakorn ◽  
Pornkiat Churnjitapirom ◽  
Theeralaksna Suddhasthira
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Orthodontic Treatment ◽  
Steel Wire ◽  
General Purpose ◽  
Stainless Steel Wire ◽  
Bending Test ◽  
Bending Properties ◽  
Steel Wires ◽  
Significant Difference

The archwire is generally used in fixed appliances for orthodontic treatment to correct dental malocclusion. However, it is interesting to know whether general purpose stainless steel wire could replace commercial orthodontic archwire in orthodontic practice for economic reasons. The purpose of this study was to determine the bending properties of general purpose stainless steel wire compared with commercial orthodontic stainless steel wires after forming as an archwire for orthodontic use. The samples used in this study were 90 general purpose and 45 commercial (Highland) round stainless steel wires in 0.016, 0.018, and 0.020 sizes (30 general purpose and 15 commercial wires for each size). All 15 general purpose stainless steel wires with different sizes were formed into orthodontic archwire with a Universal Testing Machine. All samples were tested (three-point bending test) for mechanical properties. The results showed no significant difference between general purpose and commercial orthodontic wires in size 0.016 for 0.1 mm offset bending force, 0.2% yield strength, and springback. Although many mechanical properties of general purpose wires differed from commercial wires, their values conformed to other previous studies within the range of clinical acceptance. In conclusion, orthodontic formed general purpose round stainless steel wires had statistically different (p <0.05) mechanical properties from commercial orthodontic stainless steel wires (Highland) but the mechanical properties were acceptable to use in orthodontic treatment.

SUPPLY CHAIN FORMATION IN OPEN, MARKET-BASED MULTI-AGENT SYSTEMS

2002 ◽  
Vol 02 (03) ◽  
pp. 349-363 ◽  
Author(s):  
ANEURIN M. EASWARAN ◽  
JEREMY PITT
Keyword(s):  
Supply Chain ◽  
Service Providers ◽  
Search Algorithm ◽  
Multiple Criteria ◽  
Simultaneous Optimization ◽  
Open Market ◽  
Multi Agent Systems ◽  
Complex Tasks ◽  
Hierarchical Task Network ◽  
Service Allocation

Efficient allocation of services to form a supply chain to solve complex tasks is a crucial problem. Optimal service allocation based on a single criterion is NP-Complete. Furthermore, complex tasks in general have multiple criteria that may be conflicting and non-commensurable. This paper presents a two-stage brokering algorithm for optimal anytime service allocation based on multiple criteria. In the first stage, a hierarchical task network planner is used to identify the services required to solve a task. In the second stage, a genetic algorithm (GA) determines service providers based on multiple criteria to provide the services identified by the planner. We present our algorithm and results from various experiments conducted to analyze the effect of various parameters that influence the complexity of the problem. In general, the results show the GA finds optimal solutions much quicker than a standard search algorithm. The empirical results also indicate the performance of the algorithm is sub-linear or polynomial time for various parameters. The algorithm has the ability to deal with any number of criteria. By addressing this problem, we expand the range of problems being addressed to any that require simultaneous optimization of multiple criteria and/or planning.

Sign in / Sign up

Export Citation Format

Share Document