Assessment of Life of Pressure Vessels and Pipes in Crude Oil and Gas Industries

2013 ◽  
Author(s):  
M. Shahid Khalil ◽  
Sajjad Akbar
Keyword(s):  
Oil And Gas ◽  
Pressure Vessels ◽  
Life Assessment ◽  
Hydrogen Attack ◽  
Second Stage ◽  
Safe Life ◽  
Non Destructive Evaluation ◽  
Pipe Joints ◽  
Non Destructive ◽  
Corrosion Under Insulation

Fitness-for-service (FFS) assessments are quantitative engineering evaluations which are required to be preformed periodically in accordance with the published codes and standards to demonstrate the structural integrity of in-service components. This report summarizes the results of nondestructive in-service-inspection (ISI) of pressurized components conducted for condition assessment of the Dakhani Gas Processing Plant of Oil and Gas Development Corporation Ltd. (OGDCL) for the first time since its commissioning in December,1989. The non-destructive evaluation of the plant was required because of concerns for occurrence of sulphide-stress-cracking. Hydrogen embrittlement, hydrogen-including-cracking, weight-loss-corrosion, sulphur-stress-corrosion due to determental service conditions at Dakhani having low PH, High H2S, high chlorides and pressure of CO2. The results have shown that microstructural changes associated with first and second stage of hydrogen attack have occurred in almost all of the pipe joints and pressure vessels. Hardness of some vessels has even exceeded the NACE limit of 220 HB. Effect of second stage of hydrogen attack are dominant in pipe joints, resulting in loss of hardness and strength because of decarburization. The results based on ultrasonic attenuation monitoring also indicate degradation of components. Random rounded indications have also been observed in some pipe joints during X-Ray radiographic testing that could serve as sites for failure initiation. The corrosion-under-insulation is observed for joints of piping spreading over a significant length. Localized corrosion and pitting is also observed in some locations of pressure vessels and piping. Ultrasonic thickness gauging has shown a significant variation in thickness for dish end and shell of some pressure vessels as well as for various joints of piping. In absence of periodic ISI data for the plant and keeping in view the results of non-destructive evaluation summarized above, the end-of-life (EOL) assessment of pressure vessels and piping is not possible and operation of the plant should be continued with a degree of caution. Any estimate of safe life assessment of the plant made at this stage would require revision on the basis of observed level of degradation through essential periodic in-service monitoring. In order to cope with the situation, it is recommended that monitoring of further degradation of microstructure and hardness along with flaw growth should be carried out after a period of 8x103 hours. Necessary remedial measures for rectification of flaws are requested. Non-destructive strain gauging is recommended to estimate data for safe life assessment of pressure vessels. Thermographic scanning of on-line in-service insulated pipelines is proposed for monitoring corrosion-under-insulation during plant operation.

scholarly journals NDT application for detection of corrosion under insulation in Vietnam

2021 ◽  
Vol 11 (1) ◽  
pp. 48-54
Author(s):  
The Man Nguyen ◽  
Duc Vinh Vu
Keyword(s):  
High Temperature ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Piping System ◽  
Gas Industry ◽  
Non Destructive Evaluation ◽  
The Cost ◽  
Fluid Leak ◽  
Non Destructive ◽  
Corrosion Under Insulation

: In the oil and gas Industry, insulation materials can be used widely for piping system, tank and vessel in either low or high temperature applications. CUI can cause equipment degradation, fluid leak, which lead to explosion or environmental pollution and the cost will very expensive. Therefore, CUI need to be detected early to prevent damage. Through experiment, Center for Non-Destructive Evaluation (NDE) studied on establishing and appliying 4 NDT procedures for CUI examination on typical petroleum piping using in Vietnam. A discussion is presented below

Fitness for Service of Layered Multiwalled Design Vessels

2017 ◽  
Author(s):  
Kyle Gough ◽  
Daniel Peters
Keyword(s):  
Asset Management ◽  
State Of The Art ◽  
Life Assessment ◽  
Construction Technique ◽  
Non Destructive Evaluation ◽  
Non Destructive ◽  
Art Techniques

Layered vessels have been in-service for many years which use layered construction. This construction technique has been employed since the 1930's. This generally involved either concentric plates or spirally wrapped plates to manufacture vessels with thick walls that otherwise would require very thick and heavy forgings. Long term asset management of these vessels, including non-destructive evaluation of the vessels welds and life assessment of the vessels due to operational cycling the vessels experience can be challenging. This paper is meant to address some of the challenges in managing these critical assets and provide a discussion on the application of state of the art techniques which are being applied today.

NOMAD: Non-Destructive Evaluation (NDE) System for the Inspection of Operation-Induced Material Degradation in Nuclear Power Plants — Overview of the Neutron Irradiation Campaigns

2020 ◽  
Author(s):  
Inge Uytdenhouwen ◽  
Rachid Chaouadi
Keyword(s):  
Neutron Irradiation ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Pressure Vessels ◽  
Material Heterogeneity ◽  
Non Destructive Evaluation ◽  
Surveillance Programs ◽  
Non Destructive

Abstract Worldwide there are more than 449 nuclear power plants (NPPs) in operation among which 329 reactors are older than 25 years and 94 will be operating for more than 40 years in 2020. Lifetime extensions are requested up to 50–60 years and sometimes even up to 80 years of operation for many existing NPPs. Long-term operation (LTO) of existing NPPs has therefore been accepted in many countries as a strategic objective to ensure supply of electricity for the coming decades. Within this strategy, the European Commission launched the NOMAD project, among others, through the Horizon-2020 programme. The reactor pressure vessels (RPVs) cannot be tested destructively in a direct way, neither can it be replaced. An indirect way is the use of Charpy samples from the so-called surveillance programs. The general strategy on the long term should focus on the ability to perform direct non-destructive evaluation (NDE) of the embrittlement of the vessel. NDE can be used to confirm that the data obtained by surveillance programs are being representative of the real state of the vessel for LTO. Moreover, a generic concern of large nuclear components such as the reactor vessel is the possible material heterogeneity such as macro-segregated regions which could eventually be located in the component but not in the baseline material used as surveillance material. Local non-destructive material inspection and comparison to reference materials in similar irradiation conditions would lead to a better assessment of the properties of the materials at any location of the vessel. The objective of NOMAD is to develop a tool that is capable of non-destructively evaluate the embrittlement of the vessel wall. The final system should be capable of inspecting the microstructure of the materials through the cladding. The tool that will be developed, will use existing and proven nondestructive testing techniques (NDT) with optimized and adjusted sensors. A combination of several techniques based on micro-magnetic, electrical and ultrasonic methods are investigated. Within NOMAD, they are calibrated and validated on a set of existing and newly irradiated samples consisting out of the most common RPV steels from Eastern and Western design, such as 22NiMoCr37, 18MND5, A533-B, A508 Cl.2, A508 Cl.3 and 15kH2NMFA. For the first time, a systematic study on a well-characterized set of samples that correlates the microstructure, mechanical properties, neutron irradiation conditions and non-destructive properties will be carried out. It will not only extend the existing database, but will include issues such as reliability, and uncertainty of the techniques as well as on material heterogeneity. The focus is laid on unbroken Charpy samples and large blocks with and without cladding to “simulate” the actual RPV inspection scenario. This paper gives an overview of the present status of the NOMAD project with focus on the outcome in WP1. The first preliminary NDE results from 6 set-ups and 28 parameters were compared with DBTT results from Charpy impact tests. They are very promising. Final results and detailed analysis will however only be available at the end of the project.

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