Mortar tubes pressure

Substituting typical values into equation (4.1) enables an estimate of the maximum mortar tube pressure to be made [equation (4.2)],... 

Pressure in the Mortar Tube. The maximum pressure generated in the mortar tube has been shown to be related to the ballistic parameters presented in equation (4.1),... 

Figure 4.5 Approximate pressure-time curve for combustion of lifting charge within a mortar tube.

For display shells of 200 mm and above, reinforced fibreglass mortar tubes are invariably used. Welded steel tubes have long been considered to be amongst the safest because, in the event of a pressure-burst, the tube will split in the vicinity of the weld, thus creating a predictable danger zone. With seamless tubes the fragmentation is completely random and creates a shrapnel hazard for the fireworks operator. 

BALLISTICS (INTERNAL) The science of internal ballistics is concerned with the propulsion of a projectile such as a shell along the tube of a mortar by gas pressure acting on the base of the shell, or, in the case of rockets, by the backward exhaust of the gas jet. 

A supported Pd catalyst (0.1 g) was pretreated at 200 °C for 30 min with a H2 stream. The resulting catalyst was mixed with H2TES or Na2TES (0.1 g), and die mixture was ground to a fine powder using a mortar and pestle. The mixture was placed in a Schlenk tube, and then the air in the tube was replaced by hydrogen gas. The reaction vessel was allowed to stand at 30 °C in the pressure of hydrogen (0.1 MPa) for 2 days. 

Montmorillonite K-10 clay (1.0 g) is mixed with la (0.1 g, 0.45 mmol) in solid state using a pestle and mortar or alternatively with a solution of la in dichloro-methane (2 mL). The adsorbed material is transferred to a glass tube and is inserted in an alumina bath (alumnia 100 g, mesh 65-325, Fisher scientific bath 5.7 cm diameter) inside the microwave oven. The compound is irradiated for 1.5 min (the temperature of alumina bath reached 110°C at the end of this period) and the completion of the reaction is monitored by TLC examination. The product is extracted into dichloromethane (2x15 mL) and clay is filtered off. Removal of the solvent under reduced pressure affords 2-phenyl-1,2,3,4-tetraliydro-4-quinolone 2a, in 80% yield, mp 148-150 °C. 

Disposable sample cards (option) Mortar and pestle Spatulas Mulling agent if required Tubing and connectors as required Pressure sensor Bottle for vaporization... 

Table 1.8 Hazards of Reactive Chemicals evaluated by the Pressure Vessel Test (PV), Mkm Ballistic Mortar Test (MkHI), BAM 50/60 Steel Tube Test (50/60), Test of Deflagration Violence (DF), and SADT Test (SADT)...

Take a glass tube about 90 cm. long and closed at one end, and dry and warm it. Fill it with dry, warm mercury and invert in a mortar containing the same liquid. The mercury will fall a little in the tube. Introduce a little water by means of a small pipette or by a medicine dropper, and the mercury will soon fall slightly, owing to the pressure of the water vapor — tension of aqueous vapor — in the space above the mercury. Warm the upper end of the tube with the hand or a lighted candle, and the mercury falls still lower. If it were possible to boil water in the tube, the pressure of the vapor would be equal to the pressure of the atmosphere at that instant, since water boils when it just overcomes atmospheric pres-... 

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