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The introduction of surface mount technology has changed the approach which is needed for successful rework of components. This has been brought about by the requirement of simultaneous reflow of all joints to remove the component from the board. To meet this need, manual soldering methods have been adapted, and subsequently complemented, with dedicated hot bar, hot gas and infra‐red systems. Each of these techniques with their respective applicability is considered, prior to a discussion of the parameters which need to be addressed before embarking on successful rework. All aspects of component, board and the joint itself are considered. The procedure for addressing rework is then laid out, providing a standard methodology to obtain rework joints which maintain the quality of the production joints.

BOEING are using IRCON ULTIMAX™ portable infra‐red thermometers to check heated pitot tubes mounted eight metres high on 747 aircraft fuselages by measuring the surface temperatures, remotely, from the ground.

Debonding, leading to the subsequent detachment of applied finishes to concrete buildings, is becoming a serious problem in many parts of the world. Checking building elevations by employing the technique of Infra‐red Thermography using a process developed by the writer can give advance warning of potential defects. This can enable early remedial action to be undertaken to repair a building surface before it becomes detached from the concrete substrate, possibly resulting in a hazard to passers‐by. The thermographic test method has been compared with other more traditionally used NDT methods including sounding, rebound hammer, and ultrasonic pulse velocity measurements. Although the thermographic equipment is initially more expensive, the surveying method can be shown to be faster and more accurate than any other technique currently available for this type of building evaluation.

Great savings can be achieved by detecting and isolating design problems early in an electronic programme. Many design problems, including electrical overstress, poor thermal design and circuit layout problems, are detectable by their infrared (I‐R) signature. A reliability and design improvement tool utilising current I‐R scanning technology has been developed. Specifically, an I‐R scanning method for making accurate temperature measurements for the purpose of electronic design reliability improvement and qualification has been developed and verified experimentally. Field‐actual conditions, in which radiative and convective heat losses from the components are negligible, are simulated with a thermally insulating enclosure. The enclosure is designed for rapid removal just before the scan, obviating the need for exotic materials that are transparent to I‐R in the scanner's passband. With typical hardware thermal lags, the method allows determination of true temperatures simulating field conditions. Corrections for unwanted scanner‐produced radiation and for the target emissivity are made with a three‐scan method and specially designed apparatus. An integral part of this apparatus is the aforementioned quickly removable thermal enclosure. The three scans take approximately an hour for a typical circuit board after initial set‐up time. True‐temperature measurements of circuit boards can be made with the I‐R design improvement tool now.

This paper reviews and compares the methods of kinetic heat simulation which may be used simultaneously with normal loading in structural tests of aircraft or components. Basic data on the quantities involved in and the limitations of the various techniques are given. An extensive bibliography of current literature on heat technology is provided.