Dynamite
Dynamite is an explosive based on the explosive potential of nitroglycerin, initially using diatomaceous earth (kieselguhr) as an adsorbent. It was invented by Swedish chemist and engineer Alfred Nobel in 1866 in Krümmel (Geesthacht, Schleswig-Holstein, Germany) and patented in 1867. It is usually sold in the form of a stick 20 centimetres (roughly 8 in) long and 2.5 centimetres (1 in) in diameter, but other sizes also exist. Dynamite is considered a "high explosive", which means it detonates rather than deflagrates. Another form of dynamite consists of nitroglycerin dissolved in nitrocellulose and a small amount of ketone. This form of dynamite is similar to cordite. This form of dynamite is much safer than the simple mix of nitroglycerin and diatomaceous earth/kieselguhr.
The chief uses of dynamite used to be in construction, mining, demolition, and on the battlefield. However, newer explosives and techniques have replaced dynamite in many applications. Dynamite is still used, mainly as bottom charge or in underwater blasting. Dynamite has been used in armed conflicts, mainly to destroy bridges and other ways of travel in order to slow the advance of supplies or enemy troops. Enthusiasts interested in safe-cracking have deliberately extracted nitroglycerin from dynamite by boiling the sticks and 'skimming' the nitroglycerin as it is forced out. Dynamite is also frequently used in ski resorts. The safety patrolers use sticks of dynamite to purposefully create avalanches so the runs can be safe once the skiers arrive.
Dynamite consists of three parts: nitroglycerin, one part diatomaceous earth and a small admixture of sodium carbonate. This mixture is formed into short sticks and wrapped in paper. Nitroglycerin by itself is a very strong explosive, and in its pure form it is shock-sensitive (physical shock can cause it to explode), degrading over time to even more unstable forms. This makes it highly dangerous to transport or use in its pure form. Absorbed into diatomaceous earth, nitroglycerin is less shock-sensitive.
Over time, the dynamite will "weep" or "sweat" its nitroglycerine, which can then pool in the bottom of the box or storage area. Crystals will form on the outside of the sticks. This creates a very dangerous situation. While the actual possibility of explosion without a blasting cap is minimal, old dynamite is still dangerous.
A priming device is used for initiating dynamite. The device includes a shell, usually formed of a material in a compartment at one end for housing a sensitive explosive material which is more sensitive than the dynamite to be detonated. Also included in primer units are passageways which are open at both ends of the shell for receiving and housing an electric blasting cap.
History
Dynamite was invented by Alfred Nobel and was the first safely manageable explosive stronger than black powder. Nobel patented his invention in October 1867. He originally sold dynamite as "Nobel's Blasting Powder". After its introduction, dynamite rapidly gained popularity as a safe alternative to gunpowder and nitroglycerin. Nobel tightly controlled the patent, and unlicensed duplicators were quickly shut down. However, a few United States businessmen got around the patent by using a slightly different formula. Nobel later on deeply regretted his inventing of the explosive due to its use on the battlefield as a means of killing. This led him to use the great fortune dynamite brought him to fund the Nobel Prize.
For several decades from the 1940s, the biggest producer of dynamite in the world was the Republic of South Africa, where De Beers established a factory in 1902 at Somerset West. The explosives factory was later operated by AECI (African Explosives and Chemical Industries). The demand for the product came mainly from the country's vast gold mines, centered on the Witwatersrand. The factory at Somerset West was in operation in 1903 and by 1907 was already producing 340,000 cases (22 kilograms (50 lb) each) annually. In addition, a rival factory at Modderfontein was producing another 200,000 cases per year.[1]
One of the drawbacks of dynamite was that it was dangerous to manufacture. There were two massive explosions at the Somerset West plant in the 1960s. Some workers died, but loss of life was limited by the modular design of the factory and earth works and plantations of trees that directed the blasts upwards. After 1985, production of dynamite at the factory was phased out.[2]
In the United States, dynamite was manufactured by the DuPont Corporation well into the 1990s. Dynamite was eventually eclipsed by Water gel explosives, which are safer to handle. [3]
Difference from TNT
It is a common misconception that TNT and dynamite are the same thing. Though both are high explosives, there is no other similarity between them. Where dynamite is an absorbent mixture soaked in nitroglycerin, then compacted into a cylindrical shape and wrapped in paper, TNT is a specific chemical compound.
Popular culture
- The familiar thin reddish cylinder, equipped with a fuse or blasting cap, is a stock movie prop. In comedies and cartoons, dynamite commonly explodes with the only effect being a blackened face and wild hair. In dramas, the impending explosion of lit dynamite parcels provides movie tension. In action films, dynamite is often used as a weapon.
See also
Patent
- U.S. patent 0,078,317, Improved explosive compound
- U.S. patent 3,931,763, Explosive priming device