scholarly journals Method for Emissivity Estimation of Metals

2018 ◽  
Vol 1 (1) ◽  
pp. 31-36 ◽  
Author(s):  
Emőd Filep ◽  
Dénes Nimród Kutasi ◽  
Lajos Kenéz
Keyword(s):  
Plasma Nitriding ◽  
Control Point ◽  
Point Of View ◽  
Low Alloy Steels ◽  
Estimation Model ◽  
Temperature Dependent ◽  
Research Topics ◽  
Literature Overview ◽  
Alloy Steels ◽  
And Control

Abstract Knowledge of the surface emissivity of metals is becoming more and more important both from the material science, process modelling and control point of view. Previous research results have shown that the emissivity of most metals depends on the temperature of the surface. It has also been reported that the most important temperature region is between 300 – 1000 K degrees, where the change of the emissivity is the most intense, which is also the most significant from a process control point of view [1]. We also report temperature dependent emissivity observed during plasma nitriding of low alloy steels [2]. Related to one of our present research topics the study of the low alloy aluminum (AlMg1, AlMg3) emissivity has prooven relevant. In this article the developed emissivity estimation model is presented. In the first part a literature overview and the theoretical approach of the new method is discussed, followed by the experimental results for low alloy aluminium emissivity determination and a comparison with the results available in the literature.

Study of hydrogenation and corrosion of steel equipment and pipelines at the production facilities of H2S -containing hydrocarbon raw materials

2021 ◽  
pp. 170-181
Author(s):  
R. K. Vagapov
Keyword(s):  
Raw Materials ◽  
Strength Properties ◽  
Point Of View ◽  
Low Alloy Steels ◽  
Safety And Reliability ◽  
Alloy Steels ◽  
Steel Equipment ◽  
Equipment And Pipelines ◽  
Corrosion Of Steel ◽  
The Impact

The impact of hydrogen sulfide raw materials on steel equipment and pipelines is associated not only with corrosion processes, but also with the hydrogenation of used carbon and low-alloy steels. This can lead to the loss of their strength properties and the subsequent destruction of equipment operated under conditions of increased operating pressures. Such corrosive-mechanical effects associated with the penetration of hydrogen into steel are the most dangerous from the point of view of the safety and reliability of the operation of facilities for the production of hydrocarbon fluids. The effect of H2S on the main types of structural steels was investigated according to the results of autoclave tests. The formation of blistering (blistering) and cracks on the surface of steels due to the effect of hydrogen on the steel was recorded. A study of the phase composition of corrosion products and their possible effect on the processes of corrosion and hydrogenation of steel has been carried out.

Corrosion of Weldments

2006 ◽  
Keyword(s):  
Oil And Gas ◽  
Corrosion Monitoring ◽  
Low Alloy Steels ◽  
Corrosion Resistant ◽  
Alloy Steels ◽  
Corrosion Behaviors ◽  
Nickel Base ◽  
Nonferrous Alloys ◽  
And Control ◽  
Weld Corrosion

Corrosion of Weldments provides an understanding of the causes and forms of weld corrosion and the methods used to monitor and control it. It explains how welding influences the microstructure and corrosion behaviors of carbon and low-alloy steels, stainless steels, nickel-base and other nonferrous alloys, and dissimilar metal welds. It identifies the factors that contribute to corrosion-related failures of welds and describes the underlying damage mechanisms. It presents case histories documenting corrosion problems in oil and gas, chemical processing, pulp and paper, and other industries and the challenges associated with high-temperature environments. It also covers corrosion monitoring and testing methods and provides insights on making weldments more corrosion resistant. For information on the print version, ISBN 978-0-87170-841-0, follow this link.

Human Centered Control in Robotics and Consumer Product Design

1993 ◽  
Vol 115 (2B) ◽  
pp. 271-280 ◽  
Author(s):  
Harichiko Asada ◽  
Clifford C. Federspiel ◽  
Sheng Liu
Keyword(s):  
Adaptive Control ◽  
Case Studies ◽  
Control Point ◽  
Point Of View ◽  
Air Conditioner ◽  
Air Conditioners ◽  
Human Needs ◽  
Systems And Control ◽  
Machine Communication ◽  
And Control

Human factors in the control and programming of robots and electric appliances are addressed in this paper. Systems and control techniques for the enhancement of human-machine communication as well as learning and adaptation to human needs are described with exemplary case studies. First, fundamental issues and methodologies, as well as historical perspective of relevant fields, are summarized, and two case studies are then discussed. One is user-adaptable control of air conditioners, a new type of adaptive control that allows an air conditioner to learn the thermal preference of the user. The other is a user-friendly programming method for advanced robot control. A task-level adaptive control system is developed by acquiring control skills by direct communication with human experts. The importance of human-machine communication and its impact on product development are addressed from the systems and control point of view.

scholarly journals PANORAMA IMAGE SETS FOR TERRESTRIAL PHOTOGRAMMETRIC SURVEYS

2016 ◽  
Vol III-5 ◽  
pp. 159-166 ◽  
Author(s):  
L. Piermattei ◽  
W. Karel ◽  
A. Vettore ◽  
N. Pfeifer
Keyword(s):  
Control Point ◽  
Laser Scanner ◽  
3D Models ◽  
Target Object ◽  
Point Of View ◽  
Test Field ◽  
Control Data ◽  
Projection Center ◽  
And Control

High resolution 3D models produced from photographs acquired with consumer-grade cameras are becoming increasingly common in the fields of geosciences. However, the quality of an image-based 3D model depends on the planning of the photogrammetric surveys. This means that the geometric configuration of the multi-view camera network and the control data have to be designed in accordance with the required accuracy, resolution and completeness. From a practical application point of view, a proper planning (of both photos and control data) of the photogrammetric survey especially for terrestrial acquisition, is not always ensured due to limited accessibility of the target object and the presence of occlusions. To solve these problems, we propose a different image acquisition strategy and we test different geo-referencing scenarios to deal with the practical issues of a terrestrial photogrammetric survey. The proposed photogrammetric survey procedure is based on the acquisition of a sequence of images in panorama mode by rotating the camera on a standard tripod. The offset of the pivot point from the projection center prevents the stitching of these images into a panorama. We demonstrate how to still take advantage of this capturing mode. The geo-referencing investigation consists of testing the use of directly observed coordinates of the camera positions, different ground control point (GCP) configurations, and GCPs with different accuracies, i.e. artificial targets vs. natural features. Images of the test field in a low-slope hill were acquired from the ground using an SLR camera. To validate the photogrammetric results a terrestrial laser scanner survey is used as benchmark.

Plasma nitriding of low alloy steels at floating and cathodic potentials

2008 ◽  
Vol 254 (20) ◽  
pp. 6595-6600 ◽  
Author(s):  
Liang Wang ◽  
Yang Li ◽  
Xuemin Wu
Keyword(s):  
Plasma Nitriding ◽  
Low Alloy Steels ◽  
Alloy Steels

Plasma nitriding of 42CrMo low alloy steels at anodic or cathodic potentials

2010 ◽  
Vol 204 (15) ◽  
pp. 2337-2342 ◽  
Author(s):  
Yang Li ◽  
Liang Wang ◽  
Lie Shen ◽  
Dandan Zhang ◽  
Chunhua Wang
Keyword(s):  
Plasma Nitriding ◽  
Low Alloy Steels ◽  
Alloy Steels

scholarly journals PANORAMA IMAGE SETS FOR TERRESTRIAL PHOTOGRAMMETRIC SURVEYS

2016 ◽  
Vol III-5 ◽  
pp. 159-166 ◽  
Author(s):  
L. Piermattei ◽  
W. Karel ◽  
A. Vettore ◽  
N. Pfeifer
Keyword(s):  
Control Point ◽  
Laser Scanner ◽  
3D Models ◽  
Target Object ◽  
Point Of View ◽  
Test Field ◽  
Control Data ◽  
Projection Center ◽  
And Control

High resolution 3D models produced from photographs acquired with consumer-grade cameras are becoming increasingly common in the fields of geosciences. However, the quality of an image-based 3D model depends on the planning of the photogrammetric surveys. This means that the geometric configuration of the multi-view camera network and the control data have to be designed in accordance with the required accuracy, resolution and completeness. From a practical application point of view, a proper planning (of both photos and control data) of the photogrammetric survey especially for terrestrial acquisition, is not always ensured due to limited accessibility of the target object and the presence of occlusions. To solve these problems, we propose a different image acquisition strategy and we test different geo-referencing scenarios to deal with the practical issues of a terrestrial photogrammetric survey. The proposed photogrammetric survey procedure is based on the acquisition of a sequence of images in panorama mode by rotating the camera on a standard tripod. The offset of the pivot point from the projection center prevents the stitching of these images into a panorama. We demonstrate how to still take advantage of this capturing mode. The geo-referencing investigation consists of testing the use of directly observed coordinates of the camera positions, different ground control point (GCP) configurations, and GCPs with different accuracies, i.e. artificial targets vs. natural features. Images of the test field in a low-slope hill were acquired from the ground using an SLR camera. To validate the photogrammetric results a terrestrial laser scanner survey is used as benchmark.

scholarly journals Changes of Structure and Physical-Mechanical Properties in Alloy Steels Thermochemically Treated by Plasma Nitriding

2021 ◽  
Vol 343 ◽  
pp. 03010
Author(s):  
Florin Ciofu ◽  
Marius Bibu
Keyword(s):  
Surface Layer ◽  
Plasma Nitriding ◽  
White Layer ◽  
Base Material ◽  
Point Of View ◽  
High Wear Resistance ◽  
Martensitic Structure ◽  
Free Surfaces ◽  
Alloy Steels ◽  
Complex Parts

Plasma nitriding is a method of surface modification using a glow discharge technology to introduce nitrogen into the surface of a metal, which subsequently diffuses into the material. The main advantages of plasma nitriding over conventional nitriding processes are: reduced cycle time, controlled growth of the surface layer, elimination of white layer, reduced distortion, no need of finishing, pore-free surfaces and mechanical masks instead of copper plating. The process is especially suitable for complex parts that are intensively solicited by wear, fatigue, contact pressure, shocks, possibly also to corrosion. It is applied in order to bring the metallic products in a state favourable from the point of view of structure, chemical composition and internal stress state. The paper presents an analysis of the structures and characteristics of a widely used structural steel 39 - CrAl6. As a result of plasma nitriding, a surface layer with high wear and fatigue resistance was created on the surface of the material. Also, between the surface layer and the base material was interposed a hard substrate with high wear resistance having a bainitic / martensitic structure.

Sign in / Sign up

Export Citation Format

Share Document