36 AIRCRAFT ENGINEERING October 1969 Secondly, an automatic economiser valve is incor porated for the supply of argon gas to the weld area, which is recommended when welding aluminium and its alloys. The valve permits the flow of argon gas only after the stud is in contact with the workpiece and the Tools for the Industry tool depressed in the ready-to-weld position, the gas flow being cut off immediately the weld has been made and the tool lifted from the stud. Whilst the control unit can be easily lifted and carried by the two built-in handles provided, a specially designed light steel tubular trolley mounted A Selection of Equipment of Use in the Production and Maintenance on rubber-tyred castors is also available. The control unit is carried at waist level in a con veniently inclined operating position and there is a of Aircraft, Missiles, Space Vehicles and Components holster for the handtool as well as a compartment for chucks and other accessories. A perforated metal tray shelf at the base of the trolley provides for cables and cartons of studs. The unit operates from a single-phase 50c/s. a.c. C.P. INTRODUCE PACKAGED COMPRESSOR mains supply at 110, 200, 220 or 240 volts. A 13A. RANGE supply is adequate for the 200/240V. range and a 30A. A new class R rotary stationary air compressor supply for the 110V. range. No other source of power range has been introduced by the Consolidated Pneu is required. The maximum demand is 3 kVA. matic Tool Co. Ltd., as a series of models with capaci ties of 70, 100, 160, 200, 300 and 500 cu. ft./min. at 100 lb./sq. in. Every size is available as an air or DIAMOND TOOLS USED IN GOLD water cooled model and each of these variants can TURNING be supplied with a built-in aftercooler. This extensive I.D.M. Electronics Ltd., of Reading, manufacture choice ensures that most operating conditions can be miniature precision slipring assemblies to carry satisfied from the new range. The class R machines electrical signals between stationary and rotating embody the well proven Power Vane principle of air parts of electronic systems in missiles and aircraft. compression in a new plant layout which now con Gold sliding contacts are used to avoid corrosion, tains all the ancillary equipment for a stationary and a fine surface finish of 3 microinches or better air compressor installation on one deck. This fully is needed to ensure a perfect finish. develops the inherent vibration free running and On harder metals polishing would be the obvious simple maintenance characteristics of the series to finishing technique, but it leaves abrasive particles form a unique, continuous duty, packaged com lodged in the soft gold, causing variations in electrical pressor. It is a feature of this new class R range that performance and rapid wear of the stationary contacts. the need for supplying, mounting and connecting up The only alternative is turning, and after steel and any ancillary equipment such as an air receiver, after- tungsten carbide had failed to hold the necessary cooler or an electric starter is completely eliminated. ultra-sharp edge, diamond tools were tried. It was Thus any model from the range can be supplied off found that not only did they produce the required the shelf and installed at its destination without special finish but they did so with a 0·002 in. deep final cut. foundation preparation and with only simple connec As a result of their experience in gold, I.D.M. have tion to the electrical power supply and air mains. adopted diamond tools for all turning on miniature In this new packaged form the class R series meets sliprings: shaping and grooving the cast epoxy a demand for greater flexibility in the provision of various accessories, enables rapid and consistent bodies, plunge grooving the copper substrates on compressed air for a wide range of duties. The welding of studs up to \ inch diameter (or equivalent which the contact surface is deposited, and finishing ability to provide a continuous running stationary air area) to be made to light gauge and prc-coatcd the silver surfaces of assemblies in which signal- compressor as a complete package installation to materials without damaging the rear face by heating. path quality is not quite so critical. Leinen miniature meet either long term needs or the demands of short It will weld attachments to all low carbon and stain precision lathes are used with tools supplied by the term planning enables substantial overall economies less steels down to 26 gauge and all weldable non- Majestic Diamond Tool Co., New York, and either to be made. These economics are achieved not only in ferrous metals down to 22 gauge. straight alcohol or alcohol with compressed air to reduced costs of site preparation, installation and The Cromp-Arc 250 is physically less than one- cool the work. maintenance, but also in reducing or eliminating the third the size of its predecessors and is capable of a losses due to friction and leakage associated with very high duty rate in relation to its size. Because of extending existing air mains to outlying points of the speed with which it can fix studs and its consistent useage. Additionally, the new packaged form of performance, a considerable reduction in costs in installation enables compressors to be readily sub many light engineering applications will be found stituted or removed as production demands change, possible. giving greater flexibility of production resources. The equipment has a number of significant advan As in other Power Vane compressors produced by tages such as: C.P. for continuous duty under demanding conditions, (a) The use of a thyristor solid-state device instead of air is compressed by the rotation of vanes carried in a an electro-mechanical contactor for high-speed rotor within an offset cylindrical casing, the heat of switching of the welding current. compression being absorbed by the oil injected during (b) The complete elimination of bearings and sliding the working cycle. The oil is later separated from the surfaces in the welding handtool. compressed air and is cooled in either a water-cooled (c) The provision of individual, separately adjustable or air-cooled heat exchanger before being recirculated. controls for the selection of capacitance, voltage As the efficiency of the oil separator is 99·999 per cent, and handtool spring pressure. oil consumption is negligible, being approximately (d) The welding tool incorporates a built-in argon one pint for every 300,000 cu. ft. of air produced. feed for use when welding aluminium or its alloys. The oil content of the compressed air produced is (e) An inductance within the control unit large appreciably lower than that of reciprocating machines, enough to overcome variations in the cable lead especially as service hours accumulate. Single stage to the handtool. compression is employed for the 70 cu. ft./min. and (f ) Circuit interlocking to ensure complete safety of 100 cu. ft./min. models, two stage compression being the equipment in operation. used for the rest of the range. The Control Unit is a compact sheet-steel cabinet With the direct coupling of a rotary electric motor provided with two recessed fold-down carrying to a rotary compressor no adverse out of balance handles. Housed within the cabinet are the electrical forces are created - thus foundation problems are components which, for easy servicing, have been eliminated. divided into two main sections: (a) the Power Pack, Routine oil checks and changes, periodic attentoin comprising the capacitors mounted in the base of the to filters are all the maintenance called for over very unit; (b) the Control Panel with the control com long periods. Specialised maintenance is generally not ponents and associated circuitry for charging the required until after some thousands of hours running capacitors mounted on an independent chassis in the and even this is simplified by the service exchange top half of the cabinet. For ease of access, the scheme operated by the company. chassis is carried on telescopic slides providing for complete or partial withdrawal. NEW CAPACITOR-DISCHARGE The Handtool consists of a light alloy cylindrical STUD-WELDING UNIT pistol-shaped body weighing 3½ lb. embodying certain The Cromp-Arc 250, a new advanced type of interesting features such as, firstly, the use of friction- capacitor-discharge stud-welding equipment is now less bearings. Because of this, the handtool requires available from Crompton Parkinson Ltd., a Hawker no lubrication and little maintenance, and the speed Siddeley company. This portable equipment which of the plunger is unaffected by any rise in the body consists of a control unit, a welding handtool and temncrature of the tool.
Aircraft Engineering and Aerospace Technology – Emerald Publishing
Published: Oct 1, 1969
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera