A method and a measuring range of displacements and accelerations, vertical and transversal of moving parts of railway turnouts are presented in this paper. Vertical vibrations have destructive influence for railway-track construction. Transversal vibrations are in exact relation with safety of railway traffic. These vibrations are getting up from excitations of moving track vehicles. The measurements have been made in special moving turnout points. Two presently used turnouts having the same turning radius were investigated. One of them is new generation turnout, but the second one has classical construction. In finally conclusion is drawing the relation between velocity of excitation and the values of vibration parameters. Moreover explain why to use more complicated construction in turnouts of new generation.

Natural gas, being produced from gas fields around the globe, along with a large number of other harmful substances (CO 2 , H 2 S, RSH, COS, etc.), often contains mercury. Mercury’s potentially harmful effect on humans and on the ecological system as a whole as well as the risk regarding mercury’s corrosive effects to the very sophisticated and expensive process material, equipment and catalysts is making its removal an imperative. The frequently applied procedure to remove mercury as an impurity and environment pollutant from process streams utilizes adsorption on a fixed bed consisting of sulfur impregnated activated carbon. This paper deals with data, results and more than seven years of practical field experience obtained by research of mercury removal unit efficiency during production and enhancement of natural gas at Molve, Croatia. Paper details the operating implications of handling and processing natural gas containing mercury, showing the results of the innovative approach in the process control, resulting in safety reliability and process efficiency improvements by plant modification due to change of gas flow direction.

In Croatian Podravina relatively large quantities of natural gas was discovered. From various fields (Molve, Kalinovec, Stari Gradec) natural gas is pipelined to Gas Treatment Plant (GTP) Molve. Here, at GTP Molve III, technological procedures for purification of natural gas and its distribution are performed. With yearly natural gas production of 3,5 10 9 m 3 GTP Molve III is major Croatian energy resource. Its safety and environment impact is matter of concern. Continuous acoustic emission leak monitoring system for Gas Treatment Plant (GTP) Molve as an improvement in technological and environment safety is considered. Application of a leak monitoring system under industrial conditions is a problem setting specific demands. In the paper attention is paid to some aspects of acoustic emission system implementation and the acoustic background noise definition problem. Acoustic noise measurements at a GTP Molve III were performed and some results considering background noise are presented. In the paper acoustic noise measurements performed at a GTP Molve III were presented. Across the GTP Molve III acoustical background have different spectral and amplitude characteristic. In the input area, measurements presented at a first group of measuring points included the impact of sand moved by gas fluid. Sand hits should be distinguished from acoustic emission caused by growing cracks. Motors noise and turbulence around valves are probably the main source of background noise on second group of measuring points. The conclusion is that background noise across the plant is highly different. Patterns found in one part of plant could not be applied on others measuring points. Background noise and its characterization are one of main problems solved before reliable operation of acoustic monitoring system could be applied. It is found that at GTP Molve III acoustic background is complicated, consisting of different sources at different part of a plant.

Dynamic instability induced by the initiation and development of mechanical faults in a rotary element is known to have a large negative impact on the reliability and operation safety of an entire system. This type of nonlinear system response is generally perturbed by shock impulses of extremely short time scale and amplitude. Thus difficulty presents itself in identifying and isolating features indicative of the presence and progression of faults possibly leading to mechanical deterioration. The perturbed and deteriorated states of a bearing-shaft system subjected to the actions of various types of commonly seen mechanical faults are investigated using the Numerical Hilbert Transform. The presented approach characterizes and realizes temporal events of both short and long time scales as instantaneous frequencies in the joint time-frequency domain. Examples are given to demonstrate the feasibility of applying the approach to the characterization of various deteriorating bearing states and the identification of parameters associated with several failure modes.

This investigation is directly relevant to various applications associated with the safety aspects of underbalanced drilling operations where de-oxygenated air may be co-injected with oil-based drilling fluid. However, de-oxygenated air often still contains up to 5% oxygen by volume. This residual oxygen can react with oil during the drilling process, thereby forming potentially hazardous oxidized hydrocarbons and compromising the safety of drilling operations. This article examines the conditions and processes by which oxidation reactions occur and may be helpful in reducing risk in drilling operations. This project characterizes the oxidation behaviour of several oils and a typical oil-based drilling fluid at atmospheric and elevated pressures using thermogravimetry (TG) and pressurized differential scanning calorimetry (PDSC). Tests performed on mineral matrix (core) from the oil reservoirs showed no reactivity in both inert and oxidizing atmospheres. In an inert atmosphere, tests on all hydrocarbon samples showed only vapourization, no reactivity. In an oxidizing environment, the tests on hydrocarbons showed several oxidation regions. The presence of core had no effect on the behaviour of the hydrocarbons tested in an inert atmosphere but accelerated the higher temperature oxidation reactions of the oil samples. The oil-based drilling fluid exhibited the opposite effect — the presence of core material retarded the oxidation reactions. This is perhaps due to the presence of an oxygen scavenger reacting with oxygen containing clays present in the mineral matrix. In all tests performed on mixtures of hydrocarbon and core in oxidizing atmospheres, elevated pressures resulted in acceleration of the lower and higher temperature reaction regions.

This paper will give a brief presentation of experience gained over the last 5–10 years of decommissioning of offshore installations in the North Sea. Focus is given to safety and environment issues, as this is the driven factor towards decommissioning and deconstruction of offshore installations. The establishment of cleaning criteria is based on experience from The Ekofisk I Field where a number of installations should be out of production and shut down prior to final disposal. The disposal solution was not yet defined; therefore a “cold phase” was defined. The installations would stay in place for an unknown period of time. Cleaning of large storage tanks, such as Brent Spar, Maureen Alpha and The Doris Tank is a challenge due to the size and layout of the tanks and the content, such as H 2 S, wax, scale, sediments, etc. Special cleaning techniques and methods are developed for each tank. Reuse of installation or part of the installation is a target. Re use of the installations to what they were originally designed for, has been a main issue, but not yet succeeded. In the North Sea, no installations so far have been re used. Lot of effort is put into risk management and waste management. Risk related to deconstruction work, both onshore and offshore, is a major concern. All statistics demonstrates challenges towards work performance in deconstruction projects. It is important for the offshore industry to maintain a good reputation and to be a reliable and orderly partner for safety and environmental aspects of the industry.

The Petroleum Company of Trinidad and Tobago Limited (Petrotrin) has developed and implemented a Health, Safety and Environmental (HSE) Management Audit System of its Exploration and Production, and Refining and Marketing Strategic Business Units. The main objective of this internal company audit was to determine the missing ‘gaps’ or elements from the current HSE Management System and to recommend alternate HSE Management System elements to create a more efficient Management System. The audit checklists and results effectively listed the observations, problems, and compliance issues, as well as corrective actions for improvement in accordance with the ISO 14001 and HSE Guidelines of the Exploration and Production Forum and 29CFR 1910.119 - Process Safety Management of Highly Hazardous Chemicals, Standards as well as the Company HSE key strategic directions including: • 100% compliance with local Environmental and Safety Regulations; • Targets of zero accidents and oil spills; and • Certification HSE Management Systems, for all Company operations. Senior personnel or drivers of the management systems within the Company were interviewed using this structured approach. The results from this company wide internal audit revealed that generally the overall HSE Management Strategies have been developed, but are not fully implemented, although they are formalized in the Environmental and Occupational Health and Safety Policies of the Company. HSE is undoubtedly regarded as a priority issue within Petrotrin’s operations, however there is the need to improve the documentation of formalized HSE Management System Procedures, thereby improving the enforcement and maintenance of the management system.