CZ305515B6 - Method of monitoring corrosion process of piping and vessels - Google Patents

Abstract

The method of monitoring corrosion process of piping and vessels according to the present invention is characterized in that a piping or a vessel under test fitted with built-in or additional flow-controllable valve, comprising its own or additional corrosion medium, is provided with at least one contact or contactless acoustic pickup or with a double-acting acoustic electric and electroacoustic pickup and a signal exciter of acoustic emission signals and non-linear spectroscopy of elastic waves and a photometric pickup of shade and/or absorbance. The valve modulates the corrosion medium as far as heat, pressure or chemical composition is concerned. At the same time, the pickups and exciters of the acoustic emission signals and non-linear spectroscopy of elastic waves and the photometric pickup of shade and/or absorbance are connected by means of cables to measuring and evaluation electronic blocks of the known structure, which measure, correlate and evaluate scanned or measured quantities of the acoustic emission, non-linear spectroscopy of elastic waves, shade and/or absorbance in dependence on the time of thermal or pressure or chemical modulation.

Description

Technical field

The invention relates to a method for monitoring the corrosion process of pipes and containers.

BACKGROUND OF THE INVENTION

Pipes and containers may contain liquids and gases of various corrosion activity, causing wear or damage by corrosion processes during use. The effects of corrosion on wear can be partially prevented by various corrosion protection agents and technologies, but corrosion processes can still cause emergency conditions. Despite all the advances in minimizing negative impacts, corrosion of pipelines and vessels causes considerable technical and economic damage, especially due to their emergency conditions. Therefore, it is advisable to continuously monitor pipe and vessel corrosion processes to prevent damage in a timely manner. To date, a number of methods and devices have been developed and used to monitor corrosion processes in pipes or containers. Some of them are of a normative nature, such as ČSN EN ISO 11130: "Corrosion of metals and alloys - Alternative immersion immersion test" or ČSN EN 15856: "Non-destructive testing - Acoustic emission - General principles of AE testing for corrosion detection inside a metal sheath filled with liquid ".

A common disadvantage of the methods developed and used so far is that they are mainly based on electrochemical and gravimetric measurements. If other measurements are used for corrosion monitoring, such as in the case of acoustic emission measurements in the above-cited EN 15856 standard, then they are used separately.

SUMMARY OF THE INVENTION

The above drawbacks are overcome by the method of the present invention, which is based on the simultaneous monitoring of the corrosion process by both acoustic emission (AE) and the recently developed nonlinear elastic wave spectroscopy method (Van Den Abeele, KE-A., Sutin, A., Carmeliet, J., Johnson, PA: Micro-Damage Diagnostics Using Nonlinear Elastic Wave Spectroscopy (NEWS, NDT & E International Vol. 34, 2001, 239-248.) Correlated with turbidity and / or absorbance measurements of corrosion products of its own medium transported or stored in corroded pipelines; the vessel, whereby to increase the resolution of the sensed signals of acoustic emission, NEWS and turbidity or absorbance, these are intensively modulated by the enclosed mechanical, thermal or chemical action.

The advantage of the present method of monitoring the process of corrosion of pipelines and vessels is that it enables to monitor and evaluate complex corrosion processes and the degree of corrosion damage by means of multiple sensed variables and parameters, and in particular to analyze the development of corrosion damage with higher temporal and spatial resolution. An important advantage of the method according to the invention is that it can be applied directly to the process equipment during the technological processes of carrying out their operational start-ups or shutdowns or other changes in the physico-chemical parameters of the technological processes in the pipeline or vessel under monitoring.

- 1 GB 305515 B6

DETAILED DESCRIPTION OF THE INVENTION

Example 1

A method for monitoring the pipeline and vessel corrosion process is to provide a pipeline or vessel with a built-in or additional flow-control valve containing its own or added corrosive medium to at least one touch or non-contact acoustoelectric sensor or double-acting acousto-electric and electroacoustic sensor and exciter acoustic emission signals and non-linear spectroscopy of elastic waves and a photometric turbidity or absorbance sensor. The acoustic emission and non-linear spectroscopy sensors and drivers of the elastic waves and the photometric turbidity or absorbance sensor are connected to the measuring and evaluation electronic blocks of a known structure to measure, correlate and evaluate the acoustic emission, non-linear spectroscopy waves, turbidity, or absorbance versus time.

Example 2

The method according to Example 1 is specified by increasing or decreasing the pressure in the closed pipe or vessel under test by admitting or draining the liquid medium, while acoustic emission signals and / or nonlinear elastic spectroscopy signals are simultaneously sensed, measured and correlated over time waves or turbidity or light absorbance of the discharged liquid with corrosion damage.

Example 3

Alternatively, the method of Examples 1 and 2 is modified to increase or decrease the pressure and temperature in the sealed pipeline or vessel under test by admitting or discharging a liquid medium different from the temperature of the pipeline, depending on time, At the same time, they sense, measure and correlate acoustic emission signals and / or non-linear spectroscopy of elastic waves or turbidity or absorbance of discharged liquid with corrosion damage.

Example 4

Alternatively, the method of Examples 1 and 3 is modified to increase or decrease the pressure and temperature in the sealed pipeline or vessel under test by admitting or discharging a liquid medium of a different chemical composition than that of the liquid in the pipeline under test. At the same time, they sense, measure and correlate acoustic emission signals and / or non-linear spectroscopy of elastic waves or haze or absorbance of discharged liquid with corrosion damage.

Example 5

Alternatively, the method of Examples 1 and 4 is modified to increase or decrease the pressure and / or temperature and / or chemical composition of the enclosed pipeline or vessel by allowing or discharging a liquid medium of a different temperature and composition than the temperature and composition of the liquid in the pipeline. or a vessel, wherein acoustic emission signals and / or non-linear elastic wave spectroscopy and / or turbidity or absorbance of the discharged liquid with corrosion damage are simultaneously sensed, measured and correlated with time.

-2GB 305515 B6

Example 6

Alternatively, the method of Example 5 is modified such that pressure or thermal and / or chemical modulation of the medium is performed repeatedly in a sealed pipeline or vessel under test, wherein acoustic emission signals and / or non-linear spectroscopy of elastic waves are simultaneously sensed, measured and correlated or turbidity or absorbance of the discharged liquid with corrosion damage.

Example 7

Alternatively, the embodiments of Examples 1 to 6 are specified by providing a modeled corrosion or other damage or at least one corrosion label to the test enclosed pipe or vessel, whereby the pressure or thermal or chemical modulation of the medium is performed repeatedly, depending on the medium. At the same time, they sense, measure and correlate the signals of acoustic emission or non-linear spectroscopy of elastic waves or turbidity or absorbance of discharged liquid with intrinsic and model damage.

Industrial applicability

Due to its advantages, the process of monitoring the process of corrosion of pipes and containers according to the invention can be used in virtually all industries using pipe and container technological devices. Since the process according to the invention can be carried out during other tests and inspections of pipelines and vessels, such as during shutdown or start-up of technological units, this process is applicable not only in the chemical industry. A typical application may be the use of the method of the invention to monitor for corrosion damage during the blowdown of water pipelines. Another example of the use of the method of the invention can be expected during sanitation and pipe cleaning processes in the beverage, food and pharmaceutical industries.

The use of the method according to the invention for monitoring the process of corrosion damage of containers for storing corrosive and / or harmful substances and wastes in the cleaning of process pipelines and containers in the chemical industry appears to be of particular technical and economic importance. Finally, the method of the invention will find use in both basic and applied research into corrosion processes to protect materials and equipment.

Claims (7)

PATENT CLAIMS Method for monitoring the corrosion process of pipelines and containers, characterized in that the pipeline or container with a built-in or additional flow-controlled valve containing its own or added corrosive medium is subjected to a controllable pressure of the admitted or discharged liquid medium by at least one tactile or non-contact acoustoelectric sensor or double-acting electroacoustic sensor and acoustic emission signal driver and photometric turbidity and / or absorbance sensor excites and senses acoustic emission signals and nonlinear elastic wave and / or absorbance spectroscopy, the magnitude of the readings measured by measurement and evaluation electronic blocks correspond to corrosion damage over time. -3 CZ 305515 B6 Method according to claim 1, characterized in that in the test closed pipe or vessel the pressure is increased or decreased by admitting or draining the liquid medium by means of a valve, wherein acoustic emission signals, non-linear spectroscopy of elastic materials are simultaneously sensed, measured and correlated waves, turbidity and / or light absorbance of the discharged liquid with corrosion damage. Method according to claims 1 and 2, characterized in that the pressure and temperature are increased or decreased by admitting or discharging the liquid medium different from the temperature of the test pipeline by means of a valve in the test pipe or container. sense, measure, and correlate signals of acoustic emission, non-linear spectroscopy of elastic waves, turbidity, and / or absorbance of discharged fluid with corrosion damage. Method according to claims 1 to 3, characterized in that in the test closed pipe or vessel the pressure and composition are increased or decreased by the valve by admitting or discharging a liquid medium of a different chemical composition than the chemical composition of the liquid in the test pipe or vessel. Acoustic emission signals, non-linear spectroscopy of elastic waves, turbidity and / or absorbance of discharged liquid with corrosion damage are simultaneously sensed, measured and correlated over time. Method according to claims 1 to 4, characterized in that the pressure or temperature or the chemical composition is increased or decreased by the valve by means of a valve in the test pipeline or vessel by admitting or discharging the liquid medium of a different temperature and composition than Acoustic emission signals, non-linear spectroscopy of elastic waves, turbidity and / or absorbance of the discharged liquid with corrosion damage are simultaneously sensed, measured and correlated over time. Method according to claims 1 to 5, characterized in that the pressure or thermal or chemical modulation of the medium is repeated in the closed pipeline or vessel under test, wherein acoustic emission signals, non-linear spectroscopy of elastic materials are simultaneously sensed, measured and correlated waves, turbidity and / or absorbance of the discharged liquid with corrosion damage. Method according to claims 1 to 6, characterized in that the test pipe or vessel under test is provided with a model corrosion or other damage or at least one corrosion label, wherein the pressure or thermal or chemical modulation of the medium is carried out repeatedly therein. as a function of time, they simultaneously sense, measure and correlate signals of acoustic emission, non-linear spectroscopy of elastic waves, turbidity and / or absorbance of discharged liquid with intrinsic and model corrosion damage.