This article first appeared in Practical Engineering 1940 Vol1 No23. The content of the article is accurate as of 1940. This article describes developments in Engineering at the time.
A New Optical Pyrometer
The firm of Elliott Brothers (London) Ltd., of Century Works, Lewisham, S.E.13, are noted for their wide range of high temperature measuring instruments, and one of the most recent additions to this range is a new disappearing-filament type optical pyrometer. This has been designed for measuring very high temperatures, particularly in cases where it is impracticable to employ thermo-electrical pyrometers.
This instrument is of particularly neat design, the indicator and telescope being combined in the one casing and carried on a handle which also contains the special cylindrical 2-volt "dry" accumulator. The handle will accommodate a standard T2 size dry battery if this is preferred, but the accumulator is better, as this gives a steady current supply. A terminal socket is also fitted so that a larger or existing 2-volt accumulator may be used if desired.
A range of either 800-1,400 deg. C. or 1,200-2,200 deg. C. can be provided or, if preferred, the indicator can be calibrated for both ranges. In the latter case, the changeover from one range to the other is effected by attaching an absorption screen to the objective.
Among the advantages claimed for this instrument are the following. No part of the instrument is in contact with the furnace, so that costly replacements are eliminated. It is portable, of a convenient size, and readings are obtained easily and accurately. By measuring with monochromatic light, brightness and not colour is compared; thus colour-blindness will not affect the accuracy of the readings taken.
The lamp units are easily replaced, and may be checked against one another, so that if one lamp is held in reserve, whilst the other is used constantly, the former may be employed periodically to check any variation in the latter. The principle on which the pyrometer operates was described in a recent article in Practical Engineering in which the leading types were dealt with.
Electrode Soldering Tools
Some time ago Stanelco Products, through its parent organisation, Standard Telephones and Cables, Ltd., acquired the sales and manufacturing rights for a class of soldering equipment which has been called electrode soldering.
Extensive tests were made, and such were the results obtained that it was decided to put these tools on to the British and Empire markets, since it was felt that they represented a really valuable addition to the technique of soldering.
The manufacturers do not claim that these electrode soldering tools are the solution to all soldering evils, but they do contend that, for 60 per cent, of soldering work, they do a better, quicker and cheaper job than other soldering methods. On 20 per cent, of the remainder they do an equal job, but the remaining 20 per cent, show, from experience, that the ordinary electric iron cannot be replaced on the grounds of efficiency.
Use in Electrical Work
The tools find a particularly satisfactory field of operation in all electrical work, especially with the plier tool for lugs of all sizes. The fork tools come in useful for tag contact work and the plier tools can be used for tube work. Up to the present the tools are not satisfactory for sheet metal junction work such as tin can seams and the mass production of radiators. However, we understand that a tool is under development to give this facility. At the present time tools are made in five separate sizes, the power consumption of the respective sizes being, 160 watts, 300 watts, 800-1,000 watts, 1,000 watts and 2,500 watts.