Piping flow charts

Economic Pipe Diameter, Laminar Flow Pipehnes for the transport of high-viscosity liquids are seldom designed purely on the basis of economics. More often, the size is dictated oy operability considerations such as available pressure drop, shear rate, or residence time distribution. Peters and Timmerhaus (ibid.. Chap. 10) provide an economic pipe diameter chart for laminar flow. For non-Newtouiau fluids, see SkeUand Non-Newtonian Flow and Heat Transfer, Chap. 7, Wiley, New York, 1967). 

Figure 2-3. Moody or regular Fanning friction factors for any kind and size of pipe. Note the friction factor read from this chart is four times the value of the f factor read from Perry s Handbook, 6th Ed. [5]. Reprinted by permission, Pipe Friction Manual, 1954 by The Hydraulic Institute. Also see Engineering DataBook, 1st Ed., The Hydraulic Institute, 1979 [2]. Data from L. F, Moody, Friction Factors for Pipe Flow by ASME [1].

HPAC Data Sheet, C = 40 Flow Chart for Black Steel Pipe, Heating/Piping/Air Conditioning ]n y 1981. 

For the Reynolds number range typical of drag reduction (Re 105), / is about 0.02 from the Moody chart (see Fig. 11.7). The typical turbulent intensity of gas in a pipe flow is about 5 percent. Using the Hinze-Tchen model (see 5.3.4.1), the ratio of the velocity fluctuation of the particles to that of the gas may be given by Eq. (5.196) as... 

Figure 7 Fanning friction factor chart for pipe flow. (M) piping system example (see Section 3.10) Re = 363,000, e/d = 0.0005, cp =...

For compressible fluid flow in plant piping, one can use Mak s Isothermal flow chart (Figure 1). Mak s chart was provided originally for relief valve manifold design and adopted by API. The relief valve manifold design method, and its derivation, is discussed in Section 20, Safety. Mak s methods can be applied to other common plant compressible flow situations. 

Since Mak s Isothermal flow chart is intended for relief manifold design, it supports calculations starting with P2, the outlet pressure, that is atmospheric at the flare tip, and back-calculates each lateral s inlet pressure. Pi. These inlet pressures are the individual relief valves back pressures. The chart parameter is M2, the Mach number at the pipe outlet. Having M2 is very useful in monitoring proximity to sonic velocity, a common problem in compressible flow. 

An air stream at approxin tely atmospheric temperature and pressure and containing a low concentration of carbon disulphide vapour is flowing at 38 m/s through a series of 50 mm dimneter tubes. The inside of flie tubes is covered with a thin film of liquid and both heat and mass transfer are taking place between the gas stream and the liquid film. The film heat transfer coefficient is found to be 100 W/m K. Using a pipe friction chart and assuming the tubes to behave as smooth surfaces, calculate ... 

Figure FI gives in the form of a flow chart an overview of the sequence of operations necessary to complete the construction of the piping in a process plant. For each stage there will be a programme of surveillance, inspection and tests with the completion of the corresponding records. Piping can only be released to the next stage if all the specified requirements have been met. Welding is an integral part of the prefabrication and site erection of piping, so this appendix has to be read in conjunction with Appendix D.

We now have to thank Stanton and PanneU, and also Moody for their studies of flow using numerous fluids in pipes of various diameters and surface roughness and for the evolution of a very useful chart (see Fig. 48.6). This chart enables us to calculate the frictional pressure loss in a variety of circular cross-section pipes. The chart plots Re)molds numbers (Re), in terms of two more dimensionless groups a friction factor < ), which represents the resistance to flow per unit area of pipe surface with respect to fluid density and velocity and a roughness factor e/ID, which represents the length or height of surface prelections relative to pipe diameter. 

Looking at the friction factor chart (Fig. 48.6), we see how the experimental data further confirms Reynolds earlier work and helps us even today with our own field work. Once we have determined the friction factor (j) for the pipe flow we are studying, all that remains is to evaluate the frictional pressure loss, AP from... 

Use Piping and Instrument Diagrams (P ID), Process Flow Diagrams (PFD), schematics and flow charts to identify components and relations among components. 

The exit Mach number Mo may not exceed unity Mo = 1 corresponds to choked flow sonic conditions may exist only at the pipe exit. The mass velocity G in the charts is the choked mass flux for an isentropic nozzle given by Eq. (6-118). For a pipe of finite length. 

Once the mass flux G has been determined. Fig. 6-21r or Q>-2 h can be used to determine the pressure at any point along the pipe, simply by reducing 4fL/D and computing p From the Figures, given G, instead of the reverse. Charts for calculation between two points in a pipe with known flow and known pressure at either upstream or downstream locations have been presented by Loeb (Chem. Eng., 76[5], 179-184 [1969]) and for known downstream conditions By Powley (Can. J. Chem. Eng., 36, 241-245 [1958]). 

Approximate prediction of flow pattern may be quickly done using flow pattern maps, an example of which is shown in Fig. 6-2.5 (Baker, Oil Gas]., 53[12], 185-190, 192-195 [1954]). The Baker chart remains widely used however, for critical calculations the mechanistic model methods referenced previously are generally preferred for their greater accuracy, especially for large pipe diameters and fluids with ysical properties different from air/water at atmospheric pressure. In the chart. 

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