Valve unit hydraulic diameter

Tray layout. The preliminary tray and downcomer layout is prepared in the column-sizing phase and refined during the hydraulic design phase. In addition to the parameters previously set, such parameters as hole diameter or the type of valve unit are determined. 

Decomposition Flame Arresters Above certain minimum pipe diameters, temperatures, and pressures, some gases may propagate decomposition flames in the absence of oxidant. Special in-line arresters have been developed (Fig. 26-27). Both deflagration and detonation flames of acetylene have been arrested by hydrauhc valve arresters, packed beds (which can be additionally water-wetted), and arrays of parallel sintered metal elements. Information on hydraulic and packed-bed arresters can be found in the Compressed Gas Association Pamphlet G1.3, Acetylene Transmission for Chemical Synthesis. Special arresters have also been used for ethylene in 1000- to 1500-psi transmission lines and for ethylene oxide in process units. Since ethylene is not known to detonate in the absence of oxidant, these arresters were designed for in-line deflagration application. 

A typical flow diagram for the adiabatic process is schematically shown in Figure 3(2). The feed is first adjusted to a tenmerature previously determined, and sent to a high pressure vessel. Pressure is then applied by a piston driven by a hydraulic oil unit. After the pressure reaches a predetermined value, a valve in the outlet line is opened and the mother liquor flows out. In the outlet line, a nozzle with a very small diameter is fabricated so as to regulate the flow rate of the mother liquor. As the oil pressure can be controlled as a constant, the piston is inserted inside the vessel according to the mother liquor removal so as to keep the piston head pressure as a constant. And crystals are compacted with liquid pressure decrease, which accompanies the sweating. Finally, the purified and compacted crystals form a bulky solid or cake. 

We selected our standard fixed stroke 906 size aircraft piston pump for pumping liquid nitrogen. This unit consists of 9 axial pistons 3/l6 in. in diameter), a cylinder block, a valve plate, a drive shaft supported by anti-friction roller bearings, and an aluminum housing. The pump has a theoretical hydraulic displacement of 0.095 cu, in. per revolution and a rated continuous speed of about 7, 000 RPM, with an intermittent speed rating of 12,000 RPM. 

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