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There has been a sustained interest over the past couple of decades in developing sophisticated leak detection techniques (LDTs) that are economical and reliable. Majority of current commercial LDTs are acoustics based and they are not equally suitable to all pipe materials and sizes. There is also limited knowledge on the comparative merits of such acoustics-based leak detection techniques (ALDTs). The purpose of this paper is to review six commercial ALDTs based on four decisive criteria and subsequently develop guidance for the optimal selection of an ALDT.

Numerous publications and field demonstration reports are reviewed for evaluating the performance of various ALDTs in this study to inform their optimal selection using an integrated multi-criteria decision analysis (MCDA) framework. The findings are validated using interviews of water utility experts.

The study approach and the findings will have a broad impact on the water utility industry by identifying a suite of suitable ALDTs for a range of typical application scenarios. The evaluated ALDTs include listening devices, noise loggers, leak-noise correlators, free-swimming acoustic, tethered acoustic, and acoustic emissions. The evaluation criteria include cost, reliability, access requirements, and the ability to quantify leakage severity. The guidance presented in this paper will support efficient decision making in water utility management to minimize pipeline leakage.

This study attempts to address the problem of severe dearth of performance data for pipeline inspection techniques. Performance data reported in the published literature on various ALDTs are appropriately aggregated and compared using a MCDA, while the uncertainty in performance data is addressed using the Monte Carlo simulation approach.

The objective of this paper is to develop a condition-based maintenance (CBM) scheme for pneumatic cylinders. The CBM scheme will detect two common types of air leaking failure modes and identify the leaky/faulty cylinder. The successful implementation of the proposed scheme will reduce energy consumption, scrap and rework, and time to repair.

Effective implementation of maintenance is important to reduce operation cost, improve productivity and enhance quality performance at the same time. Condition-based monitoring is an effective maintenance scheme where maintenance is triggered based on the condition of the equipment monitored either real time or at certain intervals. Pneumatic air systems are commonly used in many industries for packaging, sorting and powering air tools among others. A common failure mode of pneumatic cylinders is air leaks which is difficult to detect for complex systems with many connections. The proposed method consists of monitoring the stroke speed profile of the piston inside the pneumatic cylinder using hall effect sensors. Statistical features are extracted from the speed profiles and used to develop a fault detection machine learning model. The proposed method is demonstrated using a real-life case of tea packaging machines.

Based on the limited data collected, the ensemble machine learning algorithm resulted in 88.4% accuracy. The algorithm can detect failures as soon as they occur based on majority vote rule of three machine learning models.

Early air leak detection will improve quality of packaged tea bags and provide annual savings due to time to repair and energy waste reduction. The average annual estimated savings due to the implementation of the new CBM method is $229,200 with a payback period of less than two years.

To the best of the authors’ knowledge, this paper is the first in terms of proposing a CBM for pneumatic systems air leaks using piston speed. Majority, if not all, current detection methods rely on expensive equipment such as infrared or ultrasonic sensors. This paper also contributes to the research gap of economic justification of using CBM.

The anomaly detection task for oil and gas pipelines based on acoustic signals faces issues such as background noise coverage, lack of effective features, and small sample sizes, resulting in low fault identification accuracy and slow efficiency. The purpose of this paper is to study an accurate and efficient method of pipeline anomaly detection.

First, to address the impact of background noise on the accuracy of anomaly signals, the adaptive multi-threshold center frequency variational mode decomposition method(AMTCF-VMD) method is used to eliminate strong noise in pipeline signals. Secondly, to address the strong data dependency and loss of local features in the Swin Transformer network, a Hybrid Pyramid ConvNet network with an Agent Attention mechanism is proposed. This compensates for the limitations of CNN’s receptive field and enhances the Swin Transformer’s global contextual feature representation capabilities. Thirdly, to address the sparsity and imbalance of anomaly samples, the SpecAugment and Scaper methods are integrated to enhance the model’s generalization ability.

In the pipeline anomaly audio and environmental datasets such as ESC-50, the AMTCF-VMD method shows more significant denoising effects compared to wavelet packet decomposition and EMD methods. Additionally, the model achieved 98.7% accuracy on the preprocessed anomaly audio dataset and 99.0% on the ESC-50 dataset.

This paper innovatively proposes and combines the AMTCF-VMD preprocessing method with the Agent-SwinPyramidNet model, addressing noise interference and low accuracy issues in pipeline anomaly detection, and providing strong support for oil and gas pipeline anomaly recognition tasks in high-noise environments.

Increasing awareness of the consequences of device failures has resulted in increased reliance on Environmental Testing as an additional means of enhancing the integrity and reliability of a device. The key consideration is not the cost of the device itself, but the cost of subsequent failure, which can be as much as a hundred times greater. Seal tests are undertaken to ensure that moisture cannot get into the internal cavities of sealed ceramic, metal or glass packages. Seal security is vital to the long‐term reliability of all hermetically sealed devices. This paper outlines the techniques involved and the requirements of the MIL, BS and IEC specifications.

THE LEAK‐TEC Division of American Gas & Chemicals, Inc., has specialized in the problems of leak detection and leak location for over ten years.

This paper aims to reveal developments in sensors applied to packaging lines.

Machine vision systems including special‐purpose smart cameras and a high‐speed camera are examined. The technology of radio frequency identification (RFID) is explained, and some products relevant to packaging are highlighted. Advances in X‐ray, metal detection and gas‐leak detection equipment are discussed.

Manufacturers are making smart cameras and high‐speed cameras easier to use. There is a trend for manufacturers to provide portable as well as in‐line instrumentation, for example, in code readers and gas leak detectors. RFID is an emerging technique for improving traceability in the supply chain, and some labelling machines additionally program an embedded chip.

Tracks the latest developments in sensors for engineers in the food and pharmaceutical packaging industries.

The purpose of this paper is to review the sensor technology innovations presented at the combined manufacturing‐related shows which included Design & Manufacturing, Assembly, Electronics, Medical and Green Manufacturing and known as the Assembly and Automation Technology Show or AAT Expo.

The paper draws on in‐depth interviews with exhibitors of sensor products.

The paper notes that sensor technology is advancing rapidly to keep up with manufacturing trends such as nanotechnology, automated testing, greater interest in 100 percent testing and the need for better product quality.

The paper shows how sensor users must continue to track sensor innovations as device suppliers make rapid advances in technology to address new requirements such as nanotechnology and automated quality control while working to reduce the user's cost of employing.

This paper reviews the most common building defects and techniques for their diagnosis. Problem areas are listed by their location within a structure and the information is presented in tabular form for easy reference. The first paper in this series — ‘Effective diagnosis of material problems and defects in building and construction’ — was published in Structural Survey Volume 4 Number 1. Part 3 will be an appraisal of better known in situ testing and NDT techniques featuring specific items of equipment.

The purpose of this paper is to develop a real-time methodology to detect damages in coating and metallic structure in buried pipelines by using DC bias added to AC signal under field operation conditions, including cathodic protection.

Impedance measurements were performed on buried pipeline for different field conditions, to develop a methodology to detect and locate damages by impedance distribution along the metallic structure.

Field condition measurements were conducted as a pilot test on a buried steel pipeline segment with a diameter of 16 inches and length of 20 km. The frequency-based technology shows some differences but overall good behavior between impedance magnitudes vs localization of the interface changes at the soil-coating-steel interface at different frequencies using DC bias added to AC signal under field operation conditions, including cathodic protection.

The methodology is not applicable to highly resistive soil or high degradation coatings.

In this work, we depict a methodology that describes real time monitoring technology for buried metallic structures using AC signal. This monitoring is capable to detect and locate real time damage occurrences on the pipe surface (coating break). Field measurements include different conditions, such as temperature, soil resistivity and soil physical structure and chemical composition.

In consideration of the satisfied application in the field of the methodology, it is believed that it can be used for the monitoring of damages in pipes in areas with high consequences and hence pipe integrity can be increased.

This real-time methodology is based on the impedance distribution signal and the differential changes along the pipeline under operating conditions. The results showed good agreement with the proposed methodology, which is able to discriminate some situations inherent of field conditions by using different impedance measurements performed along ±10 km of buried steel pipeline and assuming the reference location as the cathodic protection set up.

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.