Andrzej Zagórski

Evaluation of Hydrogen Degradation by In Situ Ultrasonic Testing

In this paper, the results are presented of the ultrasonic investigations of hydrogen degradation of 09G2S carbon steel. Samples of the steel were hydrogen charged with simultaneous registration of the ultrasonic signal. The results of ultrasonic investigations were verified by Light Microscopy (LM), Scanning Electron Microscopy (SEM) and X-ray microanalysis technique (EDS). It was shown that the in-situ ultrasonic flaw detection can be used to monitor the early stages of hydrogen degradation, i.e. the formation of microcracks caused by hydrogen trapping at nonmetallic inclusions and hydrogen blistering.

Hydrogen Influence on Microstructure, Corrosion Resistance and Mechanical Properties of Low Alloy Steel and Explosively Cladded Steel Used for Hydrogen Storage Salt Caverns

The aim of this work was to investigate whether the low alloy steel and the explosively welded metals used for salt caverns equipments are susceptible to hydrogen degradation. The materials described in this article are cheap and widely used 09G2S low alloy steel and titanium grade1 as a clad material for its superior resistance to corrosive environment joined explosively with low alloy steel S355J2+N. It was observed that at the explosive bonded interface between the base steel and the stainless steel some local melting zones are formed. It was found that the cathodic hydrogen charging causes changes in the microstructure of low alloy steel and decreases the shear strength of bonds and tensile stress as well as the corrosion resistance of clads.

Acoustic Emission Testing of Cryogenic Pipelines in Operating Conditions

This chapter presents some selected results of application of the acoustic emission method for diagnostics of technical condition of cryogenic pipelines in working conditions. The aim of the research performed was to create a solution suitable for online testing of pipeline performance using acoustic emission testing method (AT) in service, under constant working parameters of operation or with a slight working pressure overload.

Evaluation of Acoustic Emission from Damaged CFRP Sheets for Air Industry Applications

In this chapter we propose a new methodology for CFRP and GFRP composite testing. One of the most important factors describing such materials is the shear modulus. The test we have carried out included a shear test with digital image correlation and acoustic emission. We proposed to use the acoustic emission method to determine degradation of fiber-reinforced composites.

Research into the Possibilities for Monitoring Technical Conditions of Underground Pipelines Using Acoustic Emission

Non-destructive testing (NDT) is of significant importance when it comes to safety evaluation of underground pipeline utilisation. In addition to regular NDT, an intelligent piston is used in a case of great diameter pipelines, although its usage is not always possible. In this respect, the results from monitoring underground pipeline defects with Acoustic Emission testing (AE) were presented. AE laboratory research was carried out to develop a methodology of measurements that could be applied in the real technological conditions. The obtained results prove the utility of AE testing in localization and monitoring defects in underground pipelines. A part of a research was carried out in real technological conditions. As a result, new guidelines were set up for scientific researches on detection and localization of material defects in underground pipelines in operating conditions. For the purpose of carrying out a project of the transport module for selected acoustic sensors was designed, which also had been equipped to a camera for visual inspection. The system for testing was additionally equipped with modules of alert notifications and remote desktop.

New Environmentally Friendly Solutions to Prevent Oil Pipelines Disasters

In this paper a newly environmental friendly Non-Destructive Testing (NDT) method for underground oil and gas pipeline networks is proposed. A suitable equipment extracts small samples of material from installed buried pipes for mechanical testing. Numerical calculations using Finite Element Analysis (FEM) proves that decreasing wall-thickness pipes is safe for in-field operating conditions. Nevertheless, those locations from where samples are cut should be monitored. For instance by means of Acoustic Testing (AT) system. New way of placing sensors is proposed. Sensors are introduced inside the pipe so that any acoustic wave changes from surrounding medium can be measured. In this type of AT a straightforward procedure must be followed to install sensors on pipe. Therefore, there is no need to uncover tested areas with qualified personnel. The research showed that the signals recorded from internal sensors are comparable to those results extracted from external ones. The study also revealed lower vulnerability to acoustic interference of the sensor placed inside the pipeline.

Mechanical and Physical Properties of Nano-Metals

In the present work, an extensive research program has been undertaken to characterise a wide spectrum of properties of nano-metals. In particular, the effect of grain refinement on such properties as fatigue, corrosion and wear resistance, conductivity and thermal stability has been studied for various nano-metals (aluminium, copper and iron alloys). The results have revealed that nano-grain refinement also improves physical properties of single phase metals. A disadvantageous effect of large (micron sized) particles, which do not undergo refinement during the processing, has been also recognized.