GB776185A - New and improved explosive elements - Google Patents

Abstract

776,185. Filling hydrostatic pressure-resistant ammonium nitrate explosive charges. IMPERIAL CHEMICAL INDUSTRIES, Ltd. June 29, 1955 [Nov. 8, 1954], No. 32220/54. Class 9 (2). Explosive elements for use at high hydrostatic pressure are produced by packing a charge of an ammonium nitrate powder explosive containing not less than 0.1 per cent. and not more than 1.0 per cent. of water, based on the ammonium nitrate, into a sheet metal canister, subjecting the canister after sealing to such a temperature and for such a time that at least a layer of the explosive close to the sides of the canister attains a temperature which is at least the transition temperature for ammonium nitrate IV to ammonium nitrate III, i.e. 32.3‹C, is below the fusion point of any solid fusible organic sensitizing agent which may be included in the explosive, and does not exceed 80‹C and thereafter allowing the canister to cool so that the explosive which is at least at the transition temperature is converted into hardened explosive. The composition may contain at least 75 per cent. ammonium nitrate and usual ingredients, e.g. vegetable tissue, sugar, starches, trinitrotoluene, aluminium powder, orthonitrotoluol, and dinitrotoluol oils. The canister may be 0.012" thick metal, and heating may be in air or water, but is preferably to 60-70‹C by total immersion in water, so that the exposive is hardened throughout. In examples ammonium nitrate (100 per cent.-30 B.S.S., 98 per cent.- 60 B.S.S., 83 per cent.-100 B.S.S., 70 per cent.- 120 B.S.S., 34 per cent.-170 B.S.S., and 7 per cent.-240 B.S.S.), containing Acid Magenta is mixed with orthonitrotoluol with or without water wet nitrocellulose (4) (1), or with anthracite and orthonitrotoluol or trinitrotoluene (2), (3), and the resulting compositions are loosely packed in tins and roll seamed.