scholarly journals Influence of deoxidizing powder on the internal surface of hot-rolled pipes

2019 ◽  
pp. 61-65
Author(s):  
O. V. Rozhkova
Keyword(s):  
Chemical Composition ◽  
Technological Process ◽  
Internal Surface ◽  
Metallographic Analysis ◽  
Pipe Rolling ◽  
Hollow Billet ◽  
Inner Surface ◽  
Hot Rolled

The article describes the experience of using deoxidizing powder in the technological process of production of hot-rolled seamless pipes; the processes that occur when applying to the inner surface of the hollow billet deoxidizing powder. The results of experimental and industrial tests of deoxidizing powder of different chemical composition are presented. The influence of the chemical composition of the deoxidizing powder on the formation of defects on the inner surface of the pipes is shown. Describes the stages of metallographic analysis of the defects on the inner surface of the pipe, provided the reasons for the formation of the defect «pipe rolling lap (skin)».

Dynamics of exit section of automatic mill of pipe rolling line

2021 ◽  
Vol 77 (2) ◽  
pp. 175-186
Author(s):  
S. R. Rakhmanov
Keyword(s):  
Differential Equations ◽  
Mechanical System ◽  
Technological Process ◽  
Dynamic Models ◽  
Dynamic Processes ◽  
Exit Section ◽  
Pipe Rolling ◽  
Automatic Mill ◽  
Hollow Billet ◽  
Rolling Line

Nonuniformity of pipe wall thickness is one of significant indices, determining quality of hot-rolled seamless pipes. One of the reasons of increased nonuniformity arising is dynamics of exit section mechanisms of pipe rolling line (PRL). Results of study of mandrel holding mechanism dynamics of PRL presented. Dynamic models of exit section, accounting parameters of technological process and inertia of a rolled hollow billet elaborated, which enabled to determine the character of dynamic processes at the exit section of PRL automatic mill. Differential equations of exit section elements motion at the exit section of PRL automatic mill were made up. The solution of the differential equations system was obtained in a numerical form by application of Runge‒Kutta method for correspondent dynamic models of exit section based on the example of calculations for ТПА-350 automatic mill. The pattern of dynamic processes arising at the exit section was specified at realization of the whole technological process of a hollow billet rolling at automatic mill, taking into consideration alternative action from the side of deformation center and mass of the rolled hollow billet. It was shown, that the specified solution of the task for three advanced dynamic models of mechanical system considerably differs from those of the known mathematical models. It was established, that the dynamics of the mandrel holding mechanism of ТПА-350 automatic mill equivalently form the mechanism of finished pipes geometry forming. Analysis of dynamic models of the mill exit section enabled to select the necessary technological and dynamic parameters of the mechanical system, to determine stable modes of hollow billets rolling at the ТПА-350 automatic mill. Results of the study of dynamics of exit section ТПА-350 automatic mill presented. A scheme of modernization of the exit section ТПА-350 automatic mill proposed, which enables to realize rational modes of operation accounting level of mechanical system dynamics and to control quality (geometric parameters) of the rolled pipes.

Seamless Pipes Manufacturing Process Improvement Using Mandreling

2021 ◽  
Vol 316 ◽  
pp. 402-407
Author(s):  
Aleksander V. Goncharuk ◽  
Viktor A. Fadeev ◽  
Maksim V. Kadach
Keyword(s):  
Rolling Mill ◽  
Cold Treatment ◽  
Internal Surface ◽  
Screw Rolling ◽  
Pipe Rolling ◽  
Rolling Mills ◽  
Metal Deformation ◽  
Screw Rolling Mill ◽  
Hot Rolled ◽  
Positive Effect

The paper discusses the specific aspects of hot rolled seamless pipes manufacture using pipe rolling plants including screw-rolling mills. The method of accuracy enhancement of pipe dimensions, as well as external and internal surface quality improvement, is proposed. The article specifies the results of computer and physical modeling of the pipes mandreling process. The application of the mandreling process within the cage using different diameter mandrels is shown. We managed to decrease the typical mark caused by the metal deformation, due to the screw-rolling mill and to manufacture pipes with more accurate dimensions, as a result of the mandreling process modeling. The results of the physical experiment on mandreling the shell pierced at the screw-rolling mill showed a positive effect from the process of hollow billet cold treatment using the mandrel.

Kerusakan Pada Material Pipa Air Bersih Akibat General Corrosion

2019 ◽  
Vol 16 (2) ◽  
Author(s):  
M. N. Setia Nusa
Keyword(s):  
Chemical Composition ◽  
Failure Analysis ◽  
External Surface ◽  
Internal Surface ◽  
General Corrosion ◽  
Water Pipe ◽  
Corrosion Attack ◽  
Corrosion Failure ◽  
Environment Factor

Water pipe of 4.5” diameter and has been operated for 8 year having failure due to corrosion attack on its external and internal surface. It is conducted failure analysis to find out the cause of corrosion by having testing examination of visual fractography, metalography,, SEM EDAX, hardness and chemical composition. Testing and examination results show that the failure / corroded pipe has a for in of general corrosion on the external surface due to environment factor or ground factor arround the pipe and on the internal surface was influenced by excessive root weld creating protrude which then causing turbolens and deposite to accelerate corrosion attack.Pipa berdiameter 4.5” yang berfungsi mengalirkan air bersih dan telah beroperasi selama 8 tahun, terjadi kerusakan berbentuk korosi pada permukaan luar pipa dan permukaan dalam. Untuk itu dilakukan analisa kerusakan untuk mengetahui penyebab terjadinya korosi dengan pengujian dan pemeriksaan secara visual,Fractography, Metallography, SEM, EDAX, Uji Kekerasan dan Uji Komposisi Kimia. Hasil pemeriksaan dan pengujian pada pipa yang rusak / korosi berbentuk jenis general korosi pada permukaan luar pipa yang diakibatkan faktor lingkungan atau tanah disekitar pipa, sedangkan pada bagian dalam pipa dipengaruhi oleh adanya lelehan pengelasan yang kurang sempurna sehingga menimbulkan benjolan yang mengakibatkan aliran air didalam pipa tidak lancar sehingga terjadi turbolensi yang menimbulkan endapan dan mengakibatkan percepatan terjadinya korosi.Keywords: Pipe, environtment, turbolens, corrosion, failure

Scale Formation Minimization on Internal Surface of Seamless Hot-Rolled Pipes

2020 ◽  
Vol 50 (5) ◽  
pp. 340-346
Author(s):  
A. V. Emel’yanov ◽  
I. I. Lube ◽  
V. I. Kuznetsov ◽  
D. A. Levchenko
Keyword(s):  
Internal Surface ◽  
Scale Formation ◽  
Hot Rolled

Strength Properties and Chemical Composition of Materials Used in Weathering Steel Bridges

2013 ◽  
Vol 739 ◽  
pp. 292-297 ◽  
Author(s):  
Vit Křivý ◽  
Petr Konečný ◽  
Viktor Urban
Keyword(s):  
Chemical Composition ◽  
Statistical Evaluation ◽  
Strength Properties ◽  
Weathering Steel ◽  
The Czech Republic ◽  
Analysis And Evaluation ◽  
Real Material ◽  
Materials Used ◽  
Hot Rolled ◽  
Rolled Plates

The paper deals with a statistical evaluation of the real material properties of weathering steels used for the construction of motorway bridges in the Czech Republic between 2001 and 2007. The statistical analysis and evaluation is carried out for a range of hot rolled plates made of S355J2W weathering steel. The paper contains an evaluation of the strength properties of the steel and its chemical composition. The paper also contains derived real values of partial factors of materials corresponding to the relevant reliability classes RC1 to RC3 pursuant to the European standard EN 1990.

Flexure based gripper to grasp hollow objects by internal surface interaction

2021 ◽  
pp. 095440622110498
Author(s):  
Rajesh Kumar ◽  
Harsh Yadav ◽  
Varan Gupta ◽  
Jitendra P Khatait
Keyword(s):  
Internal Surface ◽  
Surface Interaction ◽  
Design Development ◽  
Friction Forces ◽  
Normal Forces ◽  
Inner Surface

The paper focuses on the design, development, and evaluation of a gripper intended to hold hollow objects by interacting with the inner surface. The gripper moves towards the inside of the hollow object and grips it using the friction forces applied on the surface of the object. The design also ensures the application of variable normal forces on the surface of the object to be grasped. The mathematical architecture is verified using prototypes and experiments.

Influence of Inner Surface Defects on the Fatigue Strength of Pipe Subjected to Cyclic Internal Pressure

1978 ◽  
Vol 100 (4) ◽  
pp. 360-368
Author(s):  
Y. Yazaki ◽  
S. Hashirizaki ◽  
S. Nishida ◽  
C. Urashima
Keyword(s):  
Fatigue Strength ◽  
Internal Pressure ◽  
Test Specimen ◽  
Surface Defects ◽  
Fatigue Crack Initiation ◽  
Internal Surface ◽  
Fatigue Tests ◽  
Inner Surface ◽  
Surface Notch ◽  
Medium Diameter

Cyclic internal oil pressure fatigue tests were carried out on medium-diameter ERW pipes of API 5LX - X60 in an attempt to determine the influence of surface defects on the fatigue strength. Experimental factors investigated were the depth and location of internal surface notch in relation to the axis of pipe. The specimen was subjected to cyclic internal pressure, the cyclic rate being 0.3–0.5 Hz. During the test, Acoustic Emission (AE) techniques were applied to detect the fatigue crack initiation. Along with the aforementioned fatigue tests, pulsating tension fatigue tests were carried out on specimens with the same surface notches as the cyclic internal pressure fatigue test specimen.

scholarly journals Quality control of aluminium melt in production process

2016 ◽  
Vol 61 (Special Issue) ◽  
pp. S43-S47 ◽  
Author(s):  
M. Kotus ◽  
E. Jankajová ◽  
M. Petrík
Keyword(s):  
Quality Control ◽  
Chemical Composition ◽  
Production Process ◽  
Aluminium Alloy ◽  
Technological Process ◽  
Casting Alloy

The quality of aluminium alloy in the production process on the chemical composition basis was evaluated. The quality of casting alloy depends on the chemical composition of melt and on the technological process of production process. The basic elements such as Si, Cu, Fe, Mg and Al in melting were evaluated. The obtained data were compared with the guide data referred to in the standard for aluminium alloy.

scholarly journals Determination of system connections of hot rolled steel sheet manufacturing process

2019 ◽  
Vol 298 ◽  
pp. 00142
Author(s):  
Elena Shiriaeva ◽  
Marina Polyakova
Keyword(s):  
Technological Process ◽  
Hot Rolling ◽  
Steel Sheet ◽  
System Analysis ◽  
Rolling Process ◽  
Metal Sheet ◽  
Technical System ◽  
Analysis Application ◽  
Material Energy ◽  
Hot Rolled

System analysis is used to state links between input and output parameters of any technical system taking into consideration flows of material, energy, and information. This approach makes it possible to find effective ways for improvement of technical system parameters. The paper presents results of system analysis application for multioperational technological process steel sheet of hot rolling. Structural scheme of metal sheet hot rolling process is presented based on principles of system analysis. Hot rolling technological operations such as workpiece heating, hot rolling, cooling, and coiling are presented as subsystems. Due to the obtained schemes metal sheet parameters are stated which have to be controlled during each technological operation of hot rolling technological process. The obtained results can be used as the basics for mathematical modeling of steel sheet hot rolling operation in order to get the final product with the required set of properties.

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