AIRCRAFT TYRE

Furthermore, concentrates may also be used as conventional additives in the same polymer or in different polymers. In this way a substantive antioxidant (or modifier) system can be produced with very high effectiveness especially under aggressive environments. In comparison, under such demanding conditions, conventional antioxidants will not only lead to premature failure of the polymer but also to dangerous situations such as in the case in food contact application (packaging), medical uses of polymers (artificial joints), and failure of aircraft tyres where human lifes are at risk. 

Rubber which is deliberately rendered electrically conductive by the inclusion in the unvulcanised mix of certain types of carbon black. Conductive rubber for use in, e.g., aircraft tyres has a resistivity below about 105 to 107 ohm-cm. The changeover from the use of channel blacks to oil-based furnace blacks has conferred a degree of conductivity (sometimes unwanted) on many black rubber products, and it should no longer be assumed that any black rubber is a good electrical insulator. See Antistatic Rubber. 

The two most important nylon fibres are nylon 6 (made from e-caprolactam) and nylon 6,6 (made from hexamethylenediamine and adipic acid). They have moderately high tensile strength, limited modulus, excellent toughness, abrasion resistance, recovery and adhesive properties, and melting temperatures of about 220°C and 250°C respectively. Nylon 6,6 was at one time widely used in tyre cords and other flexible composites, but polyester and steel, on grounds of cost and modulus, have largely displaced it except for certain heavy-duty and aircraft tyres. 

Comments are reported from companies involved in the aircraft tyre industry, which aim to reassure the user about the safety of such tyres following the recent Air France Concorde crash which resulted from tyre debris puncturing the plane s fuel tank. Test and inspection methods used, the use of retreaded tyres, and the trend towards the use of radial tyres are discussed. 

It is explained that if extreme heat builds up in aircraft tyres it can lead to reversion of the compounds and tyre failure. This paper traces the development of work done in which the combination of two anti-reversion agents used in an aircraft carcass compound provided a synergistic improvement in reversion resistance. Materials and methods are detailed, results are presented and discussed, and conclusions drawn. 

Up to 40% of all aircraft tyres have to be taken out of service on account of mechanical damage. Up to now there has been practically no analysis of the effectiveness and level of reliability of tyres with widened tolerances in respect of mechanical damage, and this has led to a study of the fatigue life and service life and service reliability of such tyres, leading to considerable financial savings. 4 refs.Translation of Kauch.i Rezina, No.4, 1992, p.l2 RUSSIA... 

Aircraft tread requires a high modulus, better abrasion resistance and low heat generation. The above requirements could be satisfied by using a CV/SEV cure system with DCBS as accelerator and insoluble sulfur (IS) as crosslinker. For achieving high modulus, HMT and a resorcinol system is used. In order to reduce the heat generation, the use of Perkalink 900 has been suggested. A typical formulation for an aircraft tyre tread recipe is shown in Table 40. 

Helium To provide an inert atmosphere for welding As a coolant in nuclear reactors With 20% oxygen, as a breathing gas for deep-sea divers To inflate the tyres of large aircraft To fill airships and weather balloons (Figure 11.12) In the helium-neon laser In low-temperature research, because of its low boiling point... 

Locust aircraft were too small for pilots, but were laden with bombs and missiles, just visible under the kinked delta-wings. Most let loose their pay-loads at the receding buggy and the vehicle exploded in a massive fireball, its suspension and swollen tyres the last to be consumed. 

Tyres and related products Pneumatic tyre manufacturing dominates the rubber industry in terms of the quantity of raw rubber consumption. About 50-60% of the rubber produced in the world is used for manufacturing tyres and related items. Tyre products include pneumatic tyres and tubes, sohd tyres, t)n e flaps, retread material, and puncture repair Wts (PRKs). NR is the ideal base material for tyres for aircraft, racing cars, heavy duty vehicles such as trucks and buses, off the road vehicles, and tractors. An oil extended form of natural rubber could be used as base material for the manufacture of winter tyres [61]. 

Tires syn. tyres are the outer circumference of a wheel which makes contact with a surface. Metal tires are used on rail and other vehicles. Solid rubber tires are used in factories where they carry high loads to resist abrasion and puncture. Where the greatest need for protection from shock is required (e.g., in automobiles, aircraft, and other vehicles) pneumatic (compressed air-filled) tires are used. Tire assemblies consist of the tire and the wheel to which they are attached. Assemblies may also include rubber inner tubes which hold the air. On inflation, the edge of the tire is pressed against the rim of the wheel and forms an airtight seam or an inner tube is filled. Tires are manufactured to rated inflation pressures appropriate to the weight of the vehicle and driving conditions. 

Steel High tenacity and modulus High density Tyres cars, aircraft... 

Tyres, especially for heavy-duty automobiles and aircraft. 

Errors, accidents and hazards are reasonably predictable, however injury experience is far more difficirltto predict. It may well be that, presently, expositre outcomes are, in the main, a function of luck. There woirld be some clear examples where that is not the case. If an aircraft loses power at 30000 feet and control is lost and unable to be recovered the outcome is able to be predicted with a high degree of certainty. The same carmot be said of the tyre blow-out. 

Poly(p-phenylene terephthalamide) fibres currently have three major applications, namely as reinforcement in radial tyres and mechanical rubber goods, in ballistic protective fabrics and ropes, and as reinforcement in polymer (particularly epoxy) composites for aircraft and aerospace components. 

A tyre failure on [that aircraft type] now, you would go off the roof. But it is just a tyre failure like any of the other ones. Now it would be... 

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