Coherent Fiber-Optic Sensor for Ultra-Acoustic Crack Emissions

A coherent optical fiber sensor with adequate sensitivity for detecting the acoustic emission (AE) during the propagation of a crack in a ferrous material is presented. The proposed fiber optic sensor is successfully compared in terms of the SNR (Signal to Noise Ratio) and detectable AE energy levels to commercially available AE piezo-transducers sensors and is proven to be an effective and advantageous alternative for sensing and monitoring fatigue damage in structural applications.

Numerical Analysis on Convective Heat Transfer Enhancement by Using Ferrofluid

Ferrofluidconsist of nanoparticles of magnetic material. They to external magnetic field and become highly magnetic in the presence of same. Due to this property of ferrofluid, it is being used in many applications like energy harvesting, heat exchanger, electronic cooling, seal, lubrication and damping. Thermophysical properties of ferrofluid can be controlled by varying externally applied magnetic field. Addition of ferrofluid into base liquid, under the action of externally applied magnetic field, increases heat transfer rate. This paper focuses on enhancement in convective heat transfer due to addition of ferrous material in base liquid under the effect of externally applied magnetic field. As intensity of externally applied magnetic field will increase, convective heat transfer rate also increases.

Record Length Chrome Liner Run Using Innovative, Low-Marking, Non-Ferrous Dies on a Mechanical Casing Running Tool

Abu Dhabi National Oil Company (ADNOC) has steadily advanced toward the use of a casing running tool (CRT) vs. conventional casing running methods to improve efficiency and safety. This advancement focused mainly on 9 ⅝ in to 20 in diameter casing and utilized internal grip tools. Recently they have searched for an external-grip CRT system that would allow them to effectively run the smaller diameter liners of both ferrous and chrome (Cr) materials, especially in the extended reach drilling (ERD) wells with maximum reservoir contact (MRC). For 20 years CRT companies manufactured tools with gripping dies that could efficiently run ferrous material liners. Development of gripping mechanisms which can effectively run corrosion resistant alloy (CRA) materials has been met with varying success. Some of the challenges are to manufacture gripping dies from non-ferrous materials that will not contaminate the CRA liner and develop a gripping pattern that does not mark the CRA liner more than is accepted by API 5CRA industry standards, but maintain effective gripping force. In addition to hoisting and making up the string with no slippage it needs to perform fluid circulation at 3,000 psi. Until recently the liners were typically run in a conventional method using power-tongs. One of the tools chosen for the trial runs was a well-proven, external-grip mechanical CRT designed specifically for smaller diameter casing and liners. It has a 500-ton hoist capacity and a 5,000 psi circulation rating and was packaged with a combination float and cushion tool and a wireless torque turn sub. Dies had been designed to meet the non-contamination and acceptable marking criteria previously mentioned and would be compatible with liners possessing as much as 25% Cr. The dies had been extensively lab-tested, including heavy pull tests and torque application tests, but had not previously been used in field applications. The ERD-MRC well chosen for this trial was planned to have a record length of 6 ⅝ in, 24 ppf, 13% Cr liner with a wedge thread premium connection. In addition to not contaminating the liner, ADNOC expected an average running speed in joints per hour equivalent to the conventional casing running methods and a reduction in time during circulations. The result of the trial was 589 connections (25,035 ft liner length) successfully run with an average running speed matching their expectations. The liner displayed very minimal marks and there were no issues when hoisting or torqueing the connections. In addition, there were no rejected connections during the run. This publication will review the preparation for the run, actual run details, photos of the die marks, torque graphs and conclusions expressed by the operator with recommendations for changes moving forward.

A Research on Friction Stir Welding using M42 Tool on Aisi 1018 Steel Plates

Friction Stir Welding was mainly suitable for aluminum alloys due to low softening temperatures. It is challenging to join the high melting temperature metals due to the lack of tool materials. The main focus of this work is to study the feasibility of joining the similar or dissimilar ferrous material. The molybdenum based high speed steel acts a rotating non consumable tool to weld the two ferrous plates. The friction stir welding was achieved using vertical milling machine. Welding samples were examined by destructive and nondestructive test. The welds were produced by 3 mm plate over a range of spindle speed from 500 to 1000 rpm. The results of FSW, stir zone of hardness varies from 139 to 145 HV executed on AISI 1018 plate steel.

Effect of Shape of Magnet on the Machining of Workpiece

Viscoelastic Magnetic Abrasive finishing has achieved a wide popularity in the field of finishing as the process is capable of finishing Non-ferrous material along with the ferrous material. With the development in technology the quality and surface finish attract more attention as compare to the machining perfection and dimensional accuracy. The present paper consists of comparison of four type of magnet available in the market and one of them as self-proposed electromagnet. A single aluminium hollow cylindrical workpiece of outer diameter as 10 mm and the inner diameter as 8 mm is finished by taking the magnet one by one whose dimensions are made according to the available literature and market and are placed as two magnetic poles with 180 degrees apparats. Ansys Maxwell 16 software was used to predict the value of maximum magnetic field on the workpiece due to the shape of the magnet and it was found that the maximum magnetic field was produced by fan shape magnet of about 0.6 Tesla. From the idea of magnetic field intensity of the workpiece, the machining ability of the magnet in viscoelastic magnetic field can be produced.

Special Issue on “Mechanical Behaviour of Aluminium Alloys”

Aluminium alloys are the most common type of non-ferrous material utilised for a wide range of engineering applications, namely in the automotive, aerospace, and structural industries, among others. [...]