Boiler Pipe Research Articles

Failure analysis of the material of water boiler pipe operated in the Arctic zone of the Republic of Sakha (Yakutia)

Failure analysis of the material of water boiler pipe operated in the Arctic zone of the Republic of Sakha (Yakutia)

ANALISIS EFISIENSI BOILER DENGAN METODE INPUT– OUTPUT DI PT. JAPFA COMFEED INDONESIA Tbk. UNIT BANJARMASIN

This paper shows some of the research results. The result of this research shows that the boiler efficiency at operational condition (present) is 79,32% decreased efficiency equal to 9,19% compared with operational condition with efficiency as big as 88,51%. One of the factors analyzing the declining efficiency of the boiler is greatly influencing the heat transfer process, because if there is dirt or crust on the boiler pipe and the fouling, it will result in the process of heat transfer will decrease so that the heat transfer rate will decrease, and will also affect the amount of heat losses in the boiler.

Program praćenja degradacije materijala u eksploataciji i procjena sigurnosti konstrukcije za produženje životnog vijeka

Details of evaluation and tracking the material condition of steam boiler's pipe system, which work on high temperature was made on the basis calculations of theretically working age of the steam line's element. This calculation presents calculation of material degradation caused by crawling and small periodic fatigue. This work show a program, especially used for tracking the material's behavior of pipe system in exploitation. This program was based on the calculation of maximal effort in the wall of each steam line's part. This calculation dependens from the measure of temperature, preasure and the smollest tickness of wall this elements. In that way is possible to make the total level of material degradation. It can be concluded that this way of tracking and calculation presents the basis for a timely decision about repair, sanation, exchange or plant revitalisation or critical components, which can make it's longer lived extension.

Creep Property Measurement of Long-Term Service-Exposed 2.25Cr-1Mo Steel Boiler Pipings by Small Punch Test

Creep Property Measurement of Long-Term Service-Exposed 2.25Cr-1Mo Steel Boiler Pipings by Small Punch Test

SP creep properties of Gr.91 boiler pipings service-exposed in different USC power plants

The small punch (SP) testing technique was applied to five heats of Gr.91 steel, which had been actually used for boiler pipings in different USC power plants for long periods of time to investigate the applicability of this technique to the assessment of heat-to-heat variation of creep property. The experimental results revealed that the SP creep rupture strength and deformation behavior were quite different depending on the heat. Those differences in SP creep property, which could not be evaluated by hardness measurement, were qualitatively similar to those in standard uniaxial creep one. It was expected that the SP creep testing technique was applicable to the assessment of heat-to-heat variation for in-service boiler pipings.

Effect of Micro-Segregation on Impact Toughness of 2.25Cr-1Mo Steel after Post Weld Heat Treatment

2.25Cr-1Mo steel with high strength at high temperatures and superior hydrogen resistance is widely used as power generation boiler material in high-temperature and high-pressure environments. Following the test evaluation of the ASME Boiler and Pressure Vessel Code, specimens from the base metal of a boiler pipe were found to have impact toughness values of 386 and 28J, which are drastically different values. The analysis of the fracture surface of the 28J test specimen revealed MnS inclusions and it was found that cracks were initiated at the inclusions. Observation of the cross-section of the crack propagation front revealed that cracks propagated along the ferrite regions and precipitate voids. Inclusions were also found in the 386J impact specimen. However, the volume fraction of the inclusions was significantly less than that of the 28J specimen. It was also found that the ferrite and carbide content of the 386J specimen was less than the 28J specimen. The reason that the inclusions, ferrite, and carbide content differed in the two adjacent impact test specimens was analyzed. The effects of micro-segregation such as MnS inclusions on ferrite and carbide were compared and analyzed.

Application of SP Creep Test to Heat-to-Heat Variation Assessment of Gr.91 Boiler Pipings

Application of SP Creep Test to Heat-to-Heat Variation Assessment of Gr.91 Boiler Pipings

Assessment of Heat-to-Heat Variation of Gr.91 Boiler Pipings by Small Punch Creep Test

Assessment of Heat-to-Heat Variation of Gr.91 Boiler Pipings by Small Punch Creep Test

Consideration of Sampling Position of Small Specimens from Gr.91 Steel Boiler Pipings Base Metal

Consideration of Sampling Position of Small Specimens from Gr.91 Steel Boiler Pipings Base Metal

Evaluation of Sampling Processing Precision of Small Specimens From Gr.91 Boiler Pipings Base Metal

Evaluation of Sampling Processing Precision of Small Specimens From Gr.91 Boiler Pipings Base Metal

An automatic detection method for the boiler pipe header based on real-time image acquisition

Generally, an endoscope is used to test the inner part of the thermal power plants boiler pipe header. However, since the endoscope hose manual operation, the length and angle of the inserted probe cannot be controlled. Additionally, it has a big blind spot observation subject to the length of the endoscope wire. To solve these problems, an automatic detection method for the boiler pipe header based on real-time image acquisition and simulation comparison techniques was proposed. The magnetic crawler with permanent magnet wheel could carry the real-time image acquisition device to complete the crawling work and collect the real-time scene image. According to the obtained location by using the positioning auxiliary device, the position of the real-time detection image in a virtual 3-D model was calibrated. Through comparing of the real-time detection images and the computer simulation images, the defects or foreign matter fall into could be accurately positioning, so as to repair and clean up conveniently.

Heat Loading of Steam Boilers Heating Surfaces

This paper deals with the comparison of an analytical solution of the temperature field of a steam boiler pipe membrane wall using a numerical method calculation in the COSMOS/M programme. The result analysis showed that analytical calculating methods which are limited to 1D and 2D task types can be used for the approximate calculation of temperature in the selected locations of the membrane wall. With these methods it is not possible to obtain a complex view of the heat loading of the entire membrane wall or of the stress conditions caused by the thermal and pressure effect of steam-water mixture in the wall pipes. The results of numerical simulations have provided a complex image about the temperature and pressure distribution in the entire membrane wall of a steam boiler taking into account the material properties.

Creep Property Evaluation of Gr.91 Boiler Pipings by Small Punch Test

Creep Property Evaluation of Gr.91 Boiler Pipings by Small Punch Test

スモールパンチ試験法によるGr.91鋼製ボイラ配管のクリープ特性評価

スモールパンチ試験法によるGr.91鋼製ボイラ配管のクリープ特性評価

Evaluation of Sampling Processing Precision of Small Specimens From Gr. 91 Boiler Pipings Base Metal

Evaluation of Sampling Processing Precision of Small Specimens From Gr. 91 Boiler Pipings Base Metal

Evaluation of Sampling Position of Small Specimens from Gr.91 Boiler Pipings Base Metal

Evaluation of Sampling Position of Small Specimens from Gr.91 Boiler Pipings Base Metal

Introducing the production of continuous-cast boiler-steel billet at OAO PNTZ

The fundamental technical specifications on continuous-cast boiler-steel billet are outlined. The basic parameters of the production technology proposed for continuous-cast steel 20 and steel billet (diameter 150–550 mm) are presented, as well as test data for experimental melts of the steel. The proposed technology produces metal of high quality, meeting (or exceeding) all the requirements on steel for boiler pipe.

동파방지 발열선용 온도제어기 개발 및 전기에너지 절감 효과 분석

Although anti-freezing heating cable has been widely installed in most residential boiler pipe, there were excessive energy consumption and fire risk due to inadequate temperature control. In this paper, a new energy saving fire risk-free controller was developed by using microprocessing operation which include detection of not only boiler room temperature but also pipe surface one. Its actual effect has been verified to save more than a half of the energy consumption comparing to conventional controller through temperature and humidity chamber experiment.

Oxide thickness measurements: a suitable tool for remaining life evaluation in power plants

Boiler pipe failures are the most common cause of forced shutdown of power generation units. The oxide layer formed in the inner wall of those pipes is the main cause of overheating failures. From the measured value of the inner oxide layer, it is possible to estimate the remaining life of the component through correlation with parameters already established by the scientific community. The present paper compares the internal oxide layer thickness measurements of pipes performed by ultrasonic (non–destructive technique) and by metallography (destructive technique), in different ranges of thickness layers and an analysis of the effects of surface finishing in the reliability of the ultrasonic results. Finally, the paper analyses the remaining life calculation based on the measurement of the oxide layer thickness. The results obtained from the calculation were corroborated with a microstructural characterisation of the samples.

Influence of Boiler Pipe Cladding Techniques on their Microstructure and Properties

Abstract The aim of this work was to investigate different weld overlay coating technologies applied to steel boiler pipes and their influence on microstructure and properties of the produced overlays. The investigations were carried out on the boiler pipes weld overlaid by an Inconel 625 and cladded at various conditions (CMT, GMAW and GTAW). The investigations showed that microstructure and mechanical properties of overlaid pipes depend on cladding technology and the chemical composition of the base material.