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To obtain better fatigue resistance for marine engineering equipment welded joints in the design stage, the design method of the marine engineering equipment welded joint design stage needs to be studied.

Based on the structural stress theory, a design method of the marine engineering equipment welded joints with better fatigue performance is proposed. The effectiveness of the method is demonstrated through the simulation analysis and fatigue test of typical marine engineering equipment welded joints.

Methods based on the theoretical advantages of structural stress and the principle of ensuring that the welded joint has a low degree of stress concentration.

The design method of marine engineering equipment welded joints proposed in this study provides a set of operable design routes for technicians, which can better meet the needs of engineering applications.

The purpose of this paper is to compile a comprehensive status report on pipes/piping networks across different industrial sectors, along with specifications of materials and sizes, and showcase welding avenues. It further extends to highlight the promising friction stir welding as a single solid-state pipe welding procedure. This paper will enable all piping, welding and friction stir welding stakeholders to identify scope for their engagement in a single window.

The paper is a review paper, and it is mainly structured around sections on materials, sizes and standards for pipes in different sectors and the current welding practice for joining pipe and pipe connections; on the process and principle of friction stir welding (FSW) for pipes; identification of main welding process parameters for the FSW of pipes; effects of process parameters; and a well-carved-out concluding summary.

A well-carved-out concluding summary of extracts from thoroughly studied research is presented in a structured way in which the avenues for the engagement of FSW are identified.

The implications of the research are far-reaching. The FSW is currently expanding very fast in the welding of flat surfaces and has evolved into a vast number of variants because of its advantages and versatility. The application of FSW is coming up late but catching up fast, and as a late starter, the outcomes of such a review paper may support stake holders to expand the application of this process from pipe welding to pipe manufacturing, cladding and other high-end applications. Because the process is inherently inclined towards automation, its throughput rate is high and it does not need any consumables, the ultimate benefit can be passed on to the industry in terms of financial gains.

To the best of the authors’ knowledge, this is the only review exclusively for the friction stir welding of pipes with a well-organized piping specification detailed about industrial sectors. The current pipe welding practice in each sector has been presented, and the avenues for engaging FSW have been highlighted. The FSW pipe process parameters are characteristically distinguished from the conventional FSW, and the effects of the process parameters have been presented. The summary is concise yet comprehensive and organized in a structured manner.

In the presented study, AISI 1040 medium carbon steel and AISI 304 austenitic stainless steel parts were joined by friction welding. The welding process was carried out under optimized conditions using statistical approach. Tension tests were applied to welded parts to obtain the strength of the joints. Fatigue properties were additionally obtained experimentally under fluctuated tensile loads. Finally, notch impact tests were applied to the joints. Microstructures using microphotographs were examined in the heat affected zone of welded parts. Hardness variations in welding zone were also obtained. Experimental results were compared with those of previous studies.

The world's most powerful electron‐beam welding facility was officially commissioned in September, providing 75 k\V of beam power in a vacuum chamber measuring 7 × 3.6 × 3.6m. Single pass welds in steel up to 200m thick may be produced at high speed and prototype fabrications may be welded in the large chamber using numerically controlled manipulating equipment.

Automatic arc‐welding machines have been used in manufacturing plant for a number of years now. They are special machines for a special purpose. But one of the main problems for automatic arc‐welding machines is presented by assembly element inaccuracies. These inaccuracies arise even when the parts are being stamped in the press. What is no problem for the manual welder, for he sees the discrepancies and is able to bridge the gap, may only be solved by automatic arc‐welding machines if powerful clamping tools are used. The same problem is also present in principle when programmable inddustrial robots are used for arc welding instead of conventional automatic machines. However, initial successes have been recorded in bridging assembly element inaccuracies with an automatic program shift and pendulum movements for the welding torch attached to the industrial robot. In recent times, these features have been supplemented by the welding power source being equipped with a parameter selection unit.

The potentially highly automated process of surface mounting electronic components directly onto a substrate or printed circuit board possesses a very weak link. Component movement subsequent to placement and before or during solder reflow leads to defect conditions such as tombstoning or rotational misalignment. This work investigates the feasibility of replacing this ‘weak’ assembly step(s) with ultrasonics. The selection and modification of suitable ultrasonic equipment is described as in the bonding of chip components onto PCBs. Reliability analysis of the resultant bonds along with bond quality in terms of shear strength and appearance under scanning electron microscope and optical microscope is studied. The results show that, with certain preferred directions of ultrasonic weld, weld preload and weld time bond strengths obtained compare very favourably with those achieved with the present surface mount technology reflow process, hence establishing the feasibility of ultrasonics for this application.

The paper aims to report on a new welding technology, TIP TIG.

The principle of operation and benefits of the technology are described together with a typical application.

The study finds that the technology provides the quality of TIG welding at the speeds of MIG welding, providing significant cost savings to the user.

TIP TIG provides a good opportunity for all users of robotic MIG welding to improve the quality of their product and reduce their costs.

The paper introduces a new and useful technology to the robot industry.

The main purpose of the present work is to study the effect of tool pin profiles on mechanical properties of welded plates made with two different aluminium alloy plates.

The welded plates were fabricated with the three different kinds of pin profiled tools such as taper cylindrical, taper threaded cylindrical and stepped cylindrical pin profiles. Tensile properties of welded plates were evaluated using tensile testing machine at room temperature. Microstructures studies were carried out using scanning electron microscope.

Tensile properties were improved with the use of taper threaded cylindrical pin tool in friction stir welding process when compared with taper cylindrical and stepped cylindrical pin tools. This is due to refinement of grains and mixing of plasticized material occurred with generation of sufficient heat with the taper threaded pin tool. Through these studies, it was confirmed that friction stir welding can be used to weld Al6061 and Al2014 aluminium alloy plates.

In the present study, the friction stir welding is performed with constant process parameters such as tool rotational speed of 900 rpm, transverse speed of 24 mm/min and tilt angle of 1°.

Aluminium alloys are widely using in automotive and aerospace industries due to holding a high strength to weight property. These aluminium alloy blanks can be developed with friction stir welding method with better properties.

Very limited work had been carried out on friction stir welding of aluminium alloys of Al 6061 and Al2014 with different tool pin profiles. Furthermore, this work analyzed with tensile properties of welded plates correlated with weld zone microstructures.

New weld inspection methods superceding visual inspection are presented. Laser‐based sensor technology contained in a handheld scanner for pre‐ and post‐weld inspection enables measurement of joint preparations or finished welds and validation of their geometry against pre‐set limits, as well as the analysis of three‐dimensional images of weld beads. The range of laser‐based sensor equipment available extends to full robotic weld inspection systems, which are applied in arc and laser welding processes on production lines, such as in the automotive industry. The benefits of these systems include higher repeatability, a permanent record for generating trending information, and the production of data helpful in reducing welding consumables used, resulting in significant savings to manufacturers.

The essence of a successful weld is that the joint should possess similar properties to the parent material. In the welding of stainless materials it is essential that the corrosion resistance be preserved in the weld metal and adjacent areas. In this article the author discusses the difficulties involved and the means whereby corrosion resistance is maintained.