Percussion

After the bedrock is exposed and clean, the next procedure is drilling. The productivity of large rotary and percussion drilling rigs is such that these rigs have largely replaced lower capacity well ddUs. 

Chlorine heptoxide is more stable than either chlorine monoxide or chlorine dioxide however, the CX C) detonates when heated or subjected to shock. It melts at —91.5°C, bods at 80°C, has a molecular weight of 182.914, a heat of vapori2ation of 34.7 kj/mol (8.29 kcal/mol), and, at 0°C, a vapor pressure of 3.2 kPa (23.7 mm Hg) and a density of 1.86 g/mL (14,15). The infrared spectmm is consistent with the stmcture O CIOCIO (16). Cl O decomposes to chlorine and oxygen at low (0.2—10.7 kPa (1.5—80 mm Hg)) pressures and in a temperature range of 100—120°C (17). It is soluble in ben2ene, slowly attacking the solvent with water to form perchloric acid it also reacts with iodine to form iodine pentoxide and explodes on contact with a flame or by percussion. Reaction with olefins yields the impact-sensitive alkyl perchlorates (18). 

Abklingzeit,/. decay period, abklopfen, v.t. beat beat off, knock off scale off (Med.) percuss, abklbren, v.t. boil out (for redyeing). abkoalleUt v.t. go off, explode. — v.t. fire off. abkneifen, v.t. pinch off, nip off. abknicken, v.t. bend (sharply) crack or snap off. 

Aufschlag, m. impact percussion increase, extra (in price or tax) cuff, facing warp bound (of a ball) (Med.) application. Aufschlagebuch, n. reference book, aufschlagen, v.t. strike up or open open, unfold unbung (casks) handle (hides) set up, erect raise apply (as a poultice). — v.r. spring up strike rise (in price). — v.i. strike, impinge. 

Fall-werk, n. drop machine stamp pile driver. -wiokel, m. angle of inclination angle of fall, -ziinder, m. percussion fuse. 

Schlag, tn. stroke, blow, percussion, knock, shock, impact, jar, kick, beat apoplexy coinage, stamp, sort cutting (of wood or in... 

Schlag-versuch, m. impact test, percussion test, -wasser, n. bilge water, -welte, /. striking distance (of an electric spark), spark distance. -werk, n. striking appparatus, specif, rammer signal bell, -wetter, n. pi. fire damp. 

Stoss, m. impulse, thrust, push, blow, stroke impact, collision, percussion, shock, jolt, blimp recoil pile, heap, (of papers) file joint blast (of a horn), stossartig, a. jolting, jerky, intermittent. Stossbutter, /. farm butter, stossdlimpfend, a. shock-absorbing, cushioning. Stoss ddmpfer, m. shock absorber dash pot. -dauer, /. duration of collision, of impact, etc. (see Stoss). 

Stoss-welle, /. percussion wave, impact wave, -widerstand, m. resistance to shock, -zahl, /. number (A collisions, impact number. -zUn-der, m. percussion fuse, stottern, t.i. stutter. 

Air Hammer. This is a special downhole drilling tool for controlling severe deviation problems and for drilling very hard formations. The air hammer is an air percussion hammer system that operates from compressed air and the rotary motion of the drill siring. 

In the early 1960s efforts were made in the United States to operate vane motors and reciprocating motors with compressed air. The vane motors experienced some limited test success but were not competitive in the market of that day [84]. Out of these development efforts evolved the reciprocating (compressed) air hammers that have been quite successful and are operated extensively in the mining industry and have some limited application in the oil and gas industry [85]. The air hammer is not a motor in the true sense of rotating equipment. The reciprocating action of the air hammer provides a percussion effect on the drill bit, the rotation of the bit to new rock face location is carried out by the conventional rotation of the drill string. 

Monochromator 663, 791 Monodentate ligand 51 Morphine (and codeine) D. of (fu) 740 Mortar agate, 155 mullite, 155 percussion, 155 synthetic sapphire, 155 Muffle furnace 97 Multielement analysis 174, 184, 775 Multiple range indicators 268 Murexide 316... 

Percussion mortar 155 Perchloric acid oxidation with, 112 titration with (nonaqueous), 408 Periodates, D. of as silver iodide, (g) 483 Peroxides analysis of, (ti) 373 Persistent lines 759... 

AN 76, N.S.N. 10, K nitrate 10, K perchlorate 2 resin 2% (2) Explosives patented by Distier, Blecher and Lopez (Refs 2 3) (a) AN 88 N.S.N. 12%. It is insensitive to shock or percussion and does not explode when heated to 200° or when ignited in an open flame, but detonates with considerable brisance when strongly initiated. The brisance may be reduced by substituting either K nitrate or Amm perchlorate for part of the AN. (b) AN 85,... 

Its suitable sensitivity to friction and impact (comparable to that of MF), its stability and high flame temp, render it very suitable for percussion-fuze use. An additional asset is that LNP functions in a practically smokeless manner, leaving little residue or slag Refs 1) Mellor 8 (1928), 887 2) E.R. von... 

The compd burns explosively at 470° and produces a flaming expln when heated quickly to 500° in air. It is not decompd by percussion or friction. Cu3N is violently decompd on reaction with w, ale, coned nitric sulfuric acids. Decomps with dil mineral acids, no reaction with dll or coned alkalies. Qf —17.8kcal/mole sp ht 0.1059cal/g/°C... 

Percussion Primers, Design Requirements , Report MDC-AG614, McDonnell Aircraft Co, St Louis, Mo (30 June 1970) 3) Anon, Eng-... 

Another suggested application for the diazido nitrato compd is that of a combustible percussion primer for caseless ammo Ref L.P. Kuhn A.C. Duckworth, The Preparation of Some New Polyfunctional Organic Azides , BRL Rept 1607(1972)... 

Percussion. The act of striking one body against another with a sharp blow. As some expls, such as MF or LSt are very sensitive to such a blow (shock or impact), they may be expld (or ignited) by such action. In this case, the term percussion can be applied to initiation or priming by such action, as weil as to the expln (or deflagration or ignition) caused by percussion... 

Percussion or Explosive Bullet. A bullet provided with a percussion cap which, on impact, explds a powder charge inside the bullet... 

Primer and Caps in Vol 3, C577 and Anvil of a Percussion Primer in Vol 1, A473-L)... 

Percussion Lock. A firearm mechanism in which a cap loaded with a detonating mixt is fitted over a pierced nipple and exploded by the blow of the falling hammer. The flash of the exploding cap is carried to the charge. Its development followed that of the flintlock (See Vol 6,... 

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