Small lead block compression test

Small Block (or Small Lead Block) Compression Test for Detonators (Epreuve des petits plombs, in Fr). See "Compression Test with Small Lead Block" in Vol 3, pp C492-R to C493-L and also Esop s Test in Vol 1, p XI... 

After firing the fuze the cylinder is examined for mushrooming effect (p IIB-19 of Ref 39). This test is similar to the " Small Lead Block Compression Test , described in Vol 3 of Encycl (Ref 41, p C493-L)... 

Detonators) XXII (SENSITIVITY TO FLAME, SPARK, ELECTROSTATIC DISCHARGES, ETC) XXIII [Sensitivity to Initiation by Primary (Initiating) Explosives, Detonators and Boosters, Tests] XXIV (Small Lead Block Compression Test is described in Vol 3 of Encycl, p C493-L) XXIV (Small Lead Block Expansion Test is briefly described under Trauzl Test) XXIV (Sound Test for Detonators) XXIV (Strength of Detonators. See under INITIATING EFFICIENCY, p XVIII) XXIV (Surveillance Tests) XXIV (Taliani Test) XXV (Trauzl Test) XXVI (Vacuum Stability Test) p A2 (Abel s or Kl-Starch Test) p A573-L (Ball Drop Test for detg sensitivity of LA or other primary expls)... 

MarohaU 2, (1917),663-4 3)Reilly(1938),81 4)Kaet-Metz(1944),318 Small Lead Block Compression Test will be discussed under Compression Testa in Vol 11 Small Lead Block Compression Test for Oetenotors. See under Esop s Teat Small Leod Block Expansion Test for Oetonotors. See under Traunl Test... 

In the small Trauzl test pentryl caused an expansion of 15.8 cc., while the same weight of tetryl caused one of 13.8 cc., TNT 12.2 cc., and picric acid 12.4 cc. In the small lead block compression test, in which 60 grams of the explosive was exploded by means of a detonator on top of a lead cylinder 64 mm. long, it was found that pentryl produced a shortening of the block of 18.5 mm., tetryl 16.6 mm., picric acid 16.4 mm., TNT 14.8 mm., and diazodinitrophenol 10.5 mm. Determinations of velocity of detonation made with half-meter lengths, the explosives being... 

Epreuve des petits plombs ou Epreuve aux blocs de Hess (Small Lead Blocks Test or Blocks of Hess Test). This test, known in the USA as Lead Block Compression Test (LBCT) or Hess Crusher Tes (Stauchprobe nach Hess, in Ger) was invented in Austria by Hess. It is one of the Compression (or Crusher)Tests for Oetetmination of Brisance, described in Vol 3 of Encycl, pp C492 to C494. Its French modification, designed by La Commission des Substances Explosives, is listed on p C493-L, but not described. 

Determination of Heat Liberated on Explosion with Calorimeter (99-104) Lead Block Expansion Test (Trauzl Test) (104-06) Compression Tests with Small Lead Blocks (106-08) Testing of Detonators, which include Sand Test and Nail Test (108-14) Water Resistance of Electric Detonators (114-15) Testing Burning (Safety) Fuse (115-18) Testing Detonating Fuse (118-19)... 

In the US modification of Hess test, which has been used by Bureau of Mines under the name of Compression Test with Small Lead Block, one lead block is used. It is 38mm in diam 64mm thick and is placed upon a rigid steel support imbedded in concrete. The block is covered with a disk of annealed steel, 38mm in diam 6.4mm thick. On top of the disk is placed a lOOg charge of expl to test, provided with a No 6 blasting cap. Detonation of the expl compresses the block appr proportionally to the brisance of expl (Ref 6 pp 107-08)... 

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