Explosive Rivet

Rivets, Explosive. See under Explosive Rivets or Other Fastening Devices in Vol 6, E442-R to E445-L... 

Transition Joints. Use of explosion-clad transition joints avoids the limitations involved in joining two incompatible materials by bolting or riveting. Many transition joints can be cut from a single large-area flat-plate clad and deflvered to limit the temperature at the bond interface so as to avoid undesirable diffusion. Conventional welding practices may be used for both similar metal welds. 

Explosion-welded constmction has equivalent or better properties than the more compHcated riveted systems. Peripheral benefits include weight savings and perfect electrical grounding. In addition to lower initial installation costs, the welded system requires tittle or no maintenance and, therefore minimizes life-cycle costs. Applications of stmctural transition joints include aluminum superstmctures that are welded to decks of naval vessels and commercial ships as illustrated in Figure 11. 

USP 2410047 (1946) (Various expl rivets and other explosively blasting joints) 8)F.F.Huston et al, USP 2412886 and 2412887 (1945) (Application of the principle of expl rivets in the construction of locomotive boilers. It is claimed that completely fluid-tight joints may be produced by expanding the ends of stay bolts thru the use of expl chges) 9)L.A.Burrows W.E. 

Lawson, USP 2556465 (1951)(Improvements in explosive rivets and in charges used in them)... 

A.H.Holtzman G.R.Cowan, Ordn 50,536, March-April 1966 (Explosive rivets were introduced in 1940 for fastening purposes particularly for the aircraft industry. Early expl rivets for aircraft were made of Al more recently, high temp alloys such.as Inconel X have been employed)... 

Uses Can be used in detonators when initiated by another primary expl and functioning as an intermediate booster or when mixed with another primary exp to increase the sensitivity of the latter to flame or heat. Its mixture with LA was patented by Dynamit AG (Ref 8) for use in explosive rivets. Tetracene can also be used in primer caps where as little as 2% in the compn results in improved uniformity of percussion sensitivity... 

In 1937 rivets containing a small explosive charge in their shanks were constructed (Aircraft Factory Heinkel and Rheinisch-Westphalische Sprengstoff A. G. [131]). The composition of the explosive mixture is so selected that a slight explosion occurs on heating the head of the rivet with a hot iron. The explosion causes an expansion of the shank thus fixing the rivet in place. Explosive rivets have found wide application primarily for riveting aircraft components in which rivets are not accessible from both sides of the riveted surface. 

Only one of the acetylides(cuprous acetylide) has found application in industry as an ingredient of electric detonators. Some acetylides, as for instance, that of silver, arc probably suitable for use in primers and detonators. They also may be incorporated in LA-based compositions for expl rivets in order to reduce their ignition point(Ref 6) According to Sax(Ref 6) the toxicity of acetylides is unknown, but their expln hazards are considered to be the same as those of fulminates and azides. The acetylides must be handled with extreme care and In storage they must be kept cool and wet. Metal powders, such as finely divided Cu or Ag, should be excluded. Shipping regulations are the same as for other primary and initiating explosives Refs l)Beil 1,238-40,(104 6),[217-20] ... 

Burrows Inventions L.A.Burrows, during his work with the DuPont Co, obt many patents on explosives, igniters, initiators, fuses, explosive rivets, electric squibs, etc... 

Von Herz patented explosives for explosion rivets. Allison patented a smokeless powder the grains of which are coated with phthalide, which serves as a deterrent. 

Uses The line powder is used as component of explosive mixtures and primer compositions, in flares and various other pyrotechnic devices. The coarse powder is used in incendiary bombs. Aluminum flakes are also used as an ingredient of explosive mixtures for detonating rivets, P.9 10 ... 

Uses As a substitute for mercury fulminate in priming compositions for percussion caps. Used in combination with tetracene for explosive charges of detonating rivets, P9 10. 

Uses In priming compositions. In explosives for detonating rivets, in combination with lead azide, for the purpose of reducing the flash point of the latter,... 

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