Minimize manifold pressure drop

Zenz, F.A., Minimize manifold pressure drop. Hydrocarbon Processing and Petroleum Refiner, 41(12), 125-130, 1962. 

Spiral-Mandrel Die n The most popular die design for extrusion of blown film, in which the melt, fed into a manifold at the bottom of the die, flows up to the die lip via multiple spiral grooves. The design is capable of handling a range of resins, provides even distribution to the lip, thus helping to minimize circumferential variations in film thickness, and has relatively low pressure drop. 

Gas-Phase Transport and Parasitic Pressure Loss The channel and stack manifold design directly affects the flow and mass transport to the catalyst surfaces as well as the parasitic pressure drop. The flow through the DM and to the catalyst surface must be adequate to limit mass transport losses, and the pressure drop must be minimized. 

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