Vacuum gear operation

When the torpedo was ejected, it rushed thru the water and this spun a small turbine. This, in aim, operated a gear train that pushed the detonator into the booster car vity. The 450 yards of travel of the torpedo required for this operation gave the vacuum tubes within the mechanism time to warm up... 

There are three basic types of devolatilization equipment that have been used for the commercial manufacture of polystyrene wiped film evaporators, devolatilizing extruders and flash evaporators. In wiped film evaporators, the polymer solution is fed into a vessel under vacuum. The solution is moved into thin films along the vessel walls by a set of rotating blades. These blades continue to move the polymer through the vessel while continually renewing the surface area. The tank walls are heated to supply the required energy for devolatilization. These units are typically mounted vertically with the polymer solution fed at the top. At the bottom is a melt pool where a gear pump transfers the melt to the next unit operation, typically pelletization. 

Vacuum blowers (vacuum pumps) are used to draw waste nitrogen, carbon dioxide, and water vapor from the adsorber vessels during the evacuation step. There are two rotary-lobe blowers operating in series. They are positive displacement machines. A timing gear arrangement maintains the close tolerances that are essential for ef cient operation. 

Hash devolatilization is a simple and effective method to remove the majority of solvent and unreacted monomers from the polymer solution. Product from the reactor is charged to a flash vessel and throttled to vacuum conditions whereby the volatile solvent and monomers are recovered and condensed. In the process, the polymer melt cools, sometimes considerably, due to the evaporation of volatiles. The polymer product is pumped from the bottom of the flash vessel with a gear pump or other suitable pump for viscous materials. Critical to operation of the flash devolatilization unit is prevention of air back into the unit that reduces stripping ability and potentially allows oxygen into the unit that can discolor products or pose a safety hazard if low autoignition temperature solvents are used. Often one flash devolatilization unit is insufficient to reduce the residual material to a sufficient level and thus additional units can be added in series [61]. In each vessel, the equilibrium concentration of volatile material in the polymer melt, is a function of the pressure and temperature the flash unit operates at, with consideration for the polymer solvent interaction effects described by the Hory-Huggins equation. Flash devolatilization units, while simple to operate, may be prone to foam development as the superheated volatiles rapidly escape from the polymer melt. Viscous polymers or polymers with mixed functionalities... 

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