Ball-pein hammers

You ean see, ba.sed on the veloeity head formula, a eavitation bubble impacts the impeller and other pump parts at about 155,069 psi. Other experiments in test laboratories using a more preeise rHv, have calculated the impact pressure at 1 Gigapascal, or 147,000 psi. This is the reason that the damage from eavitation appears like someone was beating on your impeller with a large ball pein hammer. 

Impact sensitivity can be gauged by striking a few crystals of the compound on a metal last with the ball of a ball-pein hammer. Ignition, smoking, cracking or other sign of decomposition are considered hazardous. 

The first thing that we did was to test the hardness of the hammer. The results are shown in Fig. 13.9. The steel is very hard near the striking face and the ball pein, but... 

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