Valve assemblies, illustration

Numerous solvent intensive procedures are facilitated by the installation of direct liquid transfer feedthroughs. The assembly illustrated in Figure 5 may be easily installed into either aluminum or Lexan glovebox panels using only an electric hand drill.(9) The primary components consist of a Swagelock(3) 1/8" OD tube to bulkhead male connector and a Whitey(lO) 3-way Ball valve, and all liquid connections employ 1/8" OD Teflon (5) or stainless steel tubing. 

Although intrinsically contained, the complexity could lead to operator error and automation of the valve sequencing could be beneficial. Jefferis and Schlager applied a quantitative risk assessment technique based on a fault tree analysis to a similar bioreactor sampling valve assembly. Their analysis illustrated the benefits of automation. 

Figures 29-19 and 29-20 illustrate two different mecbanical-hydraulic systems. Figure 29-19 is a bar-lift steam chest with a heavy-duty hydraulic seivo. The speed-sensing element is a flyball assembly attached to a rotating pilot. This rotating pilot sends a control-pressure signal that is proportional to speed to a bellows on the seivo. A change in control pressure initiated through the rotating pilot by either speed or speed changer deflects the bellows and seivo pilot valve. The seivopiston position is proportional to the control pressure.

Figure 10-175 illustrates the assembly of a typical forced draft unit with electric motor and gear drive. Note that walkways and access ladders are necessary to reach the exchanger connections where valves are usually installed. If... 

Figure 10 below illustrates a mock up of the initial target structures we will build with the assembly tank. By selectively plugging some of the holes in the structures we can pre-valve them (while the smart cubes are being developed) and assembly multi-cube structures like the C U structures shown in the figure. We note that the latches on the structures are sufficiently strong that they can support the weight of the structure after the assembly fluid is drained. 

FIGURE 39.1 Schematic illustrations of common microfluidic features utilized in microchip separation devices (a) top view of a multilayer assembly of microchannels formed by capping a layer with etched channels, (b) side view of micropatterned channel with capping flhn layer, (c) side view of a vacnmn-driven three-layer negative pressure valve, (d) side view of a positive pressure valve. 

It is characteristic that traditional industries which maintain older plants (metal fabrications, polymer fiber, rubber plastics, wood furniture, organic chemicals) contribute more to releases and transfers of solvents (as measured by releases plus transfers per 1000 sales), than industries which invest capital in the improvement of equipment, safety, and research and development (e.g., printing, motor vehicle assembly). This suggests that the avoidance of cost of the required investment is one reason for pollution. This reason was illustrated in the discussion of the petroleum industry where one manufacturer almost eliminated pollution by fixing leaking valves. 

FIGURE 2.5 Illustration of a SIA-LOV microflow network as assembled for in-valve sorptive preconcentration using renewable sorbent materials prior to further detection via peripheral analytical instruments. SP, syringe pump HC, holding coil. The inset at the right shows how the sorptive beads are retained within the column positions. (Reprinted with permission from Miro, M., and E. H. Hansen. 2007. Miniaturization of environmental chemical assays in flowing systems The lab-on-a-valve approach vis-a-vis lab-on-a-chip microfluidic devices. Anal. Chim. Acta 600 46-57.)... 

A1.3.1 Azobenzene Percolation Column, glass constructed from 12.0-mm outside diameter and 6.0-mm outside diameter standard glass tubing with a reservoir of approximately 125 mL near the top. The top of the column shall be a female spherical ground-glass joint. The bottom of the cblumn has a stopcock with internal metering valve attached by means of a standard taper joint. The entire percolation assembly is illustrated in Fig. 3. 

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