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The purpose of this paper is to propose a buoyancy-gravity adjustment device and a fuzzy intelligent controller for the depth control of a storage tank in-service inspection robot.

The structure of the robot is first designed based on the construction of the bottom of a crude oil tank and explosion-proof requirements. The buoyancy-gravity adjustment system is used to control the vertical movement of the robot. The motion analysis of the robot indicates that the diving or rising process is influenced by hydrodynamic force and umbilical cord tension. Considering the nonlinear model in-depth control, a fuzzy intelligent controller is proposed to address the depth control problem. The primary fuzzy controller is used to compensate for initial error with fast response. The secondary fuzzy controller is activated by an intelligent switch to eliminate the steady error.

The proposed fuzzy controller can better solve the complicated hydrodynamic problem of the coupling of umbilical cord and the robot during depth control by classifying the error values of depth, velocity and acceleration.

The buoyancy-gravity adjustment device and the depth control system of the robot can move through the heating coils by safe and accurate diving or rising.

This paper aims to introduce a new acoustic positioning method to solve the problem of space positioning for online inspection robots within the storage tank.

The proposed positioning system comprises two acoustic signal emitters and two receivers. Emitters are brought by the robot into the storage tank. Receivers are mounted on the external edge of the storage tank floor. The spatial coordinate values and motion directions of the robot in the storage tank are calculated by using the proposed acoustic positioning algorithm.

The experiment results and positioning error analysis indicate that the method can obtain the data of robotic space coordinates and motion orientation, while the positioning error of the method can be less than 20 cm. The accuracy reaches the positioning technology level of other tank online inspection robots.

This method not only expands the positioning of the inspection robots from 2D plane to 3D space but also significantly reduces the number of positioning sensors carried by a robot and improves the safety of a robot in the tank.

To present an entirely new technology to be used in the in‐service inspection of storage tanks for hazardous products in several different industries.

Current interior storage oil tank plate inspection is a very expensive and time‐consuming task. The related tasks involve high cost, several hazards to environment and the operators involved in the cleaning jobs. Several research areas were investigated during the development of this tool, fundamentally robotics and non‐destructive test tools. Initial trials in laboratory were complemented with a field test program in near‐real conditions.

A new design of tool for in‐service inspection of such equipments proved to be feasible to be constructed and operated and in accordance with current safety regulations.

New robotics application in non‐destructive testing methodologies for application in in‐service storage equipments. The internal conditions possible to find in the interior of a storage tank, like fixtures, properties of the stored products (inflammable and aggressive), sludge and sand on the bottom, no ambient light, etc., are significant challenges to the development of such a tool.

Developed a robotized tool for inspection of the floor and walls of in‐service tanks, in order to allow an evaluation of the condition of the plates of these tanks, avoiding the long period, hazards and high costs necessary for creating the conditions for reality out of service inspection.

The novelty of the RobTank Inspec project could be evaluated from the two or three existing competitors in the world, and the results of the surveys undertaken.

The purpose of this paper is to present an overview of storage tank incidents and the causes of the incidents. The paper also seeks to present a brief overview on Abu Dhabi Company for Onshore Oil Operations (ADCO) experience of Jebel Dhanna (JD) export terminal.

Major hazard installations (MHIs) store large quantities of flammable material in storage tanks. Storage tanks represent important capital assets and are often critical operational items. The failure of a tank can have several undesirable effects such as endangering personnel, affecting the environment and interrupting the operator's business. The storage tank incidents and ADCO's experience on operating of an export terminal are collected from several sources such as technical articles, text books, internet web sites, and internal reports. The incidents and the causes of the incidents are reviewed and summarised. The ADCO's experience in operation of a crude oil tank farm are outlined.

The world has witnessed 480 tank fire incidents in the period 1951‐2003. The major cause of storage tank fire incidents was due to lightning. The leaks and the spills from the tanks were due to corrosion, operation, improper or lack of maintenance, poor design and/or maintenance of piping systems, fire and explosion. Although several studies have been carried out to record the tank incidents and the causes of the incidents the studies were not comprehensive. Many tank fire incidents that occurred have not been recorded in the previous studies. ADCO have been operating the JD crude oil terminal for more than three decades without a major incident. This was achieved through the design, operation and maintaining of the tanks in accordance with international standards, periodical studies by expert consultancy, and regular development of the control and protection systems with up‐to‐date technology.

The findings highlight that an international storage tank incidents database should be established to compile the scattered data in one site. The tank incidents database encourges the MHIS to publish tank incidents. The database can assist MHIs as well as the research institutes to learn lessons from the incidents. MHIs publishing articles is one of the means of sharing and exchanging the experience with similar installations and institutes.

The purpose of this paper is to present the results of acoustic emission (AE) and ultrasonic inspection of two H₂S storage tanks carried out in a heavy water plant, in order to characterize point type defects observed during earlier ultrasonic inspection and to ensure that these defects are not growing during hydrotesting of the tanks.

Using multiple AE sensors and AE source location methodology, the entire tank could be covered to detect and locate any dynamic sources of AE associated with local plastic deformation and/or growing discontinuities from any part of the tank during the hydrotest. For confirmation of the results obtained by AE, ultrasonic inspection on the tanks and on virgin plates from which the tanks were manufactured, were carried out.

The AE signals generated during first pressurisation are attributed to the micro yielding of the material of the tanks. A few scattered AE events were observed at a few locations during the hydrotesting of the tanks and these are due to structural and rubbing noise. During hold periods and repressurising cycle of the hydrotesting, no detectable AE events were observed and this confirmed the absence of any growing discontinuity in the tanks during the hydrotesting. Ultrasonic inspection on the tanks and on virgin plates confirmed that the point type defects detected are manufacturing defects and not formed during service life.

The combined results from AE and ultrasonic techniques confirmed the structural integrity of the tanks and ensured their healthiness for continued operation.

The paper brings out the use of AE and ultrasonic techniques for monitoring hydrotesting of storage tanks of a heavy water plant. The storage tanks where point type defect indications were reported during previous ultrasonic inspection and whether these defects are growing during hydrotesting of the tanks or not, were required to be known before the tanks are put in to further service. AE signals collected during pressurising and repressurising cycles of the hydrotest and subsequent inspection by ultrasonic confirmed the vessels to be free from growing defects during the hydrotest and provided baseline data for future inspection.

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

Automatic robots can improve the efficiency of liquefied petroleum gas (LPG) tank inspection and maintenance, but it is difficult to achieve high-precision spatial positioning and navigation on tank surfaces. The purpose of this paper is to develop a spatial positioning robotic system for tank inspection. The robot can accurately identify and track weld paths. The positioning system can complete robot’s spatial positioning on tank surfaces.

A tank inspection robot with curvature-adaptive transmission mechanisms is designed in this study. A weld path recognition method based on deep learning is proposed to accurately identify and extract weld paths. Integrated multiple sensors, the positioning system is developed to improve the robot’s spatial positioning accuracy. Experiments are conducted on a cylindrical tank to test weld seam tracking accuracy and spatial positioning performance of the robotic system. The practicality of the robotic system is then verified in field tests.

The robot can accurately identify and track weld seams with a maximum drift angle of 4° and a maximum offset distance of ±30 mm. The positioning system has excellent positioning accuracy and stability. The maximum angle and height errors are 3° and 0.08 m, respectively.

The positioning system can improve the autonomous performance of inspection robots and solve the problems of weld path recognition and spatial positioning. Application of the robotic system can promote the automatic inspection and maintenance of LPG tanks.

This paper deals with the causes and mechanisms of internal corrosion of tanks used for the storage of crude oil and distillates. Services which are considered in this paper include crude oil storage tanks, gasoline blending and/or storage tanks and storage tanks for kerosene and heavier distillates. Fixed‐roof, as well as floating‐roof tanks, are considered. Methods for corrosion prevention and control are discussed.

The purpose of this paper is to report an investigation into acoustic emission (AE) characteristics of the corrosion situation of the bottom of a large storage tank.

Guard sensors were applied in on‐line AE inspection of a tank bottom, and the AE signal characteristics of the corrosion areas of tank bottom were analyzed. The AE test results were compared with those from an internal tank internal test.

It was observed that guard sensors could shield effectively a large proportion of the extraneous noise signals inside the tank. The characteristics of AE signals from different types of corrosion were significantly different. A comparison of AE test results and tank internal inspection data showed a good agreement.

Characteristic AE signals from different types of corrosion were obtained for the first time, which assisted in the identification of the tank bottom corrosion situation.

The general outline of nature and extent of corrosion that can occur, both internally and externally, are described and some methods of inspection enumerated. Repair and/or mitigation methods available are also discussed. (This paper was originally presented at the Second Kuwait Symposium of the Institute of Petroleum, March 1964.)