Detonating cord

Pentaerythritol tetranitrate is a high energy explosive that is used as a pressed base charge in blasting caps and detonators, as the core explosive in commercial detonating cord, and as the main explosive ingredient in sheet explosives. It is also mixed in various proportions with TNT to form the less sensitive pentoHtes, eg, PETN 50/TNT 50. PETN is easily initiated, its responses are reproducible, and it is readily available (144—146). 

E. E. Kilmer, Detonating Cords Eoaded with HNS Recrystallic dfrom Acid and Organic Solvents, TR 75-142, NSWC, White Oaks, Md., 1975. 

In general terms, PETN can be characterized as a sensitive , brisant, and powerful high expl. Explosive sensitivity is a rather nebulous quantity, but there can be no doubt that PETN is a much more sensitive material than TNT, but rather less sensitive than Lead Azide. In particular, PETN requires very little priming i charge (less than 1 mg LA) to initiate its detonation. This is the characteristic that makes PETN so widely used in blasting cap base charges, in detonating cord and in boosters... 

When detonating cord is not required directly to initiate high explosives, but solely to transmit detonation from one place to another, it is sometimes an advantage to use a cord with a very low charge weight. Two types of such cord are at present available in certain countries. 

L.E.D.C. Low Energy Detonating Cord. A detonating fuse with a core charge too low to enable it to be used reliably for initiating high explosives (see p. 124). 

The techniques described are not so complex as to require a chemical laboratory or machine shop however, many of them do assume access to basic demolitions and incendiary supplies, such as explosives, time (safety) fuse, detonating cord, blasting caps, and flammable materials, and to a few household tools. 

Primacord, or detonating cord, differs from time fuse in that it detonates practically instantaneously along its entire length rather than burning progressively and relatively slowly. 

Slit open about 1 yard of primacord with a sharp knife and collect the powder on a piece of clean paper or in some clean container. (NOTE The explosive used in primacord usually is PETN. Other explosives sometimes used in detonating cord are Tetryl, RDX, and TNT. In this technique Tetryl will work as well as PETN. The others may not.)... 

Explosives are generally detonated with the assistance of initiating devices (initiators) that are activated by external stimulation sources (friction, spark, or flame), and may include (1) primers, (2) detonators, (3) electric detonators, (4) safety fuses, and (5) detonating cord. 

A detonating cord is used for simultaneous detonation of a number of explosive charges. The cord is comprised of a core (often made of Pentrit), cotton threads around a core, and a plastic coating. A detonating cord with a Pentrit core has a detonation velocity of approximately 6500 meters/second and is initiated by a blasting cap.9... 

Pentaerythritol tetranitrate (PETN) is a colorless crystalline solid that is very sensitive to initiation by a primary explosive. It is a powerful secondary explosive that has a great shattering effect. It is used in commercial blasting caps, detonation cords, and boosters. PETN is not used in its pure form because it is too sensitive to friction and impact. It is usually mixed with plasticized nitrocellulose or with synthetic rubbers to form PBXs. The most common form of explosive composition containing PETN is Pentolite, a mixture of 20 to 50% PETN and TNT. PETN can be incorporated into gelatinous industrial explosives. The military has in most cases replaced PETN with RDX because RDX is more thermally stable and has a longer shelf life. PETN is insoluble in water, sparingly soluble in alcohol, ether, and benzene, and soluble in acetone and methyl acetate. 

Figure 6.13. Experimental arrangement of the hot-explosive compaction method for the preparation of consolidated Ni-Al alloys (after Kecskes etal. 2004). (a) Precursor powder sample inside a steel-tube container placed in, (b) an asbestos thermal insulation sheet (c) a concentric card-box filled with the powdered explosive (80% NH4NO3 + 20% TNT) (d) threaded steel plugs serving as contacts for the preliminary heating and to be lifted off just before detonating the explosive (e) detonating cords.

About 10 30 in the morning, April 20th, I wandered outside the plant and over to where I had stashed the plug-in. Before plugging in the extension cord I checked the circuit breaker in the block house to ensure it was in the OFF position. Then I plugged in the detonation cord and went back into the block house and shut the steel door tight. .. I wanted to make sure I did not blow up in the explosion. 

Pentaerythritol tetranitrate (PETN) (3) is a powerful explosive which exhibits considerable brisance on detonation (VOD 8310 m/s at = 1.77 g/cm ). It is the most stable and least reactive of the common nitrate ester explosives. The relatively high sensitivity of PETN to friction and impact means that it is usually desensitized with phlegmatizers like wax and the product is used in detonation cord, boosters and as a base charge in detonators. Pentaerythritol tetranitrate can be mixed with synthetic polymers to form plastic bonded explosives (PBXs) like detasheet and Semtex-IA. A cast mixture of PETN and TNT in equal proportions is known as pentolite and has seen wide use as a military explosive and in booster charges. The physical, chemical and explosive properties of PETN commend its use as a high explosive. 

Without disturbing the main charge, cut the detonating cord or other leads between the disarmed firing device and the main charge. 

Cord Detonating or Cordeau. See Vol 3, p C529-R and also Detonating Cords or Detona-... 

Detonating Cord, SpeciaL See Vol 2, p B17-L under Bangalore Torpedoes... 

Sand Test (Essai au sable) (69) Nail Test (Essai au clou) (69) Tests for Electric Detonators (69-70) Tests for Fuses (Essais des meches) (70) Tests for Detonating Cords (Essais des cordeaux detonants)... 

Dynamite primers with LEDC (low energy detonating cord) delay assemblies made by the DuPont Co are described in Ref 50, pp 106-09 192-93. They are essentially nonelectric MS(microsecond) delay caps"... 

Detonating Cord. See Cord, Detonating in Ref 48, p C529-R and Detonating Cord or Fuse in Ref 48, p D103... 

Concussion Detonator Ml, Delay Type is a mechanical firing device actuated by the concussion wave of a nearby blast. It fires several charges simultaneously without connecting them by wires or detonating cord. A... 

It consists of a casing fitted with a gasket, two suspension lugs, a hinge tube, an electric cable, two fuzes AN-M152A1 (described in Ref 51a, p 3-77), a burster (detonating cord), fin assembly M13 and arming wire assembly M23... 

Bomb Adapter-Booster, T59, shown in Fig 5-6 of Ref 51a (not reproduced here), is used to ignite the detonating cord which opens leaflet bomb M139- Adapter is metallic cylinder 2.89-inches in diam, 6.03-in long, which contains Tetryl booster charge (Ref 51a, p 5-9)... 

Fig 24 (Primer, percussion M39A1) 50-2 (Time blasting fuse) 52-4 (Detonating cord) 54-69 [Firing devices and components for demolition charges, boobytraps and mines. 

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