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It is well known that the prefabricated vertical drain (PVD) installation process generates a significant soil disturbance around PVD. This disturbed zone significantly affects the rate of settlement and excess pore pressure dissipation. However, the characteristics of these zones were still uncertain and difficult to quantify; there remains large discrepancy among researchers. This study aims to develop a simple analytical solution for radial consolidation analysis of PVD-installed deposit considering mandrel-induced disturbance.

The proposed solution takes into account the nonlinear distributions of both horizontal hydraulic conductivity and compressibility toward the drain. The proposed solution was applied to analyze field behavior of test embankment in New South Wales, Australia.

Both effects significantly increased the time required to achieve a certain degree of consolidation. The effect of hydraulic conductivity on the consolidation rate was more significant than the effect of compressibility variation. And, the increased compressibility in the soil-disturbed zone due to mandrel installation significantly increased vertical strain of the PVD-improved soil deposit. The predicted results using the proposed analytical solution were in good agreement with the field measurements.

A geotechnical engineer could use the proposed analytical solution to predict consolidation behavior of drainage-installed ground.

Consolidation behavior of PVD-installed ground could be reasonably predicted by using the proposed solution with considering variations of both hydraulic conductivity and compressibility due to PVD installation.

A Heli‐Coil insert is defined quite simply; it is diamond section wire formed into a helical coil and wound, by means of appropriate tooling, into a pre‐tapped hole. Made mainly from austenitic nickel chrome stainless steel — it is also available in phosphor bronze, Nimonic 90 and Inconel X‐750 it provides a permanent thread, wholly resistant to wear and the effects of corrosion. High temperatures are taken care of by the use of heat resistant nickel alloy and Inconel wire.

The purpose of this paper is to propose an innovative method to extend the operating range of the laser tracking system and improve the accuracy and automation of boresighting by designing a measurement instrument. Boresighting is a process that aligns the direction of special equipment with the aircraft reference axis. Sometimes the accurate measurement and adjustment of the equipment and the aircraft are hard to achieve.

The aircraft is moved by an automatic adjustment system which consists of three numerical control positioners. For obtaining the position of the bore axis, an instrument with two measurement points is designed. Based on the multivariate normal distribution hypothesis, an uncertainty evaluation method for the aiming points is introduced. The accuracy of the measurement point is described by an uncertainty ellipsoid. A compensation and calibration method is proposed to decrease the effect of manufacturing error and deflection error by the finite element analysis.

The experimental results of the boresighting measurement prove that the proposed method is effective and reliable in digital assembly. The measurement accuracy of the angle between the bore axis and the reference axis is about ±0.004°. In addition, the measurement result is mainly influenced by the position error of the instrument.

The results of this study will provide a new way to obtain and control the installation deviation of part in aircraft digital assembly and will help to improve the precision and efficiency. This measurement method can be applied to obtain the axis of a deep blind hole.

A researcher at Northwestern University's McCormick School of Engineering and Applied Science (Evanston, Illinois) has developed an X‐ray device that is believed to be the first practical means of detecting corrosion hidden beneath the surface of an aircraft's body. When the “virtual core drill” is positioned against the side of an aircraft, a computer screen shows an image of the layers of metal under the surface of the skin. If one or more of those layers are corroded, the amount of corrosion will be recorded on the screen, to an accuracy of 1/1.000 of an inch. The virtual core drill or, more technically, a Compton backscatter depth profilometer, was invented by Larry Lawson, research scientist at the McCormick School's Centre for Quality Engineering and Failure Prevention. The device sends con‐trolled X‐ray beams through the plane's body and detects those X‐rays that are deflected back at an angle near 90° from each layer. Today, whenever corrosion is detected on aircraft, the section must be dismantled, the layers pulled apart, and a micrometer used to measure the thickness. If the corrosion represents more than 10 per cent. the part must be replaced. The virtual core drill can eliminate the downtime and the damage that occurs when aircraft have to be torn apart for inspection. The new device includes a 200lb scan head, which is attached to the plane using feet shaped like suction cups while supported by a flexible boom mounted on a vehicle resembling a fork‐lift truck. The vehicle moves the scan head up and down the aircraft. The drill is equipped with the most sensitive detector known, the sodium iodide scintillator. The drill provides the same kind of information, layer by layer, as would be provided by cutting a plug out of the aircraft with a core drill, except that the aircraft is undamaged. Radiation exposure also is minimal.

THE U.S. Air Force recently ordered twenty‐seven C‐97 Strato‐freighters in addition to the thirteen previously ordered, some of which have been delivered. These are the cargo version of the Boeing Aircraft Company's Stratocruiser.

As a result of the increasing costs of protecting conventional pipes a number of alternative pipe materials have been introduced in the last two decades with considerable emphasis on plastics. Thus a range of thermo‐plastics such as PVC or Polyethylene have been used for both pressure and non pressure applications in the smaller diameters but the most significant addition to the range of pipe materials has been that of fibre reinforced composites particularly glass fibre reinforced plastics (GRP).

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 current issue of the journal of the Institute of Practitioners in Work Study, Organisation, and Methods one of its Members, a Mr. E. Cule Davies, plausibly argues that ‘professional standards’ are interdependent with what he terms ‘practical results’. Mr. Davies cites a notional case of a company inviting a ‘specialist’ (the quote marks are his) to improve productivity in a given section and who gave their own professional work study practitioner the same objective to attain.