Pumping pipe fittings

Impervious graphite centrifugal pumps, pipe fittings, and valves were developed because most chemical processes require the movement of Hquids. Graphite pipe and fittings in sizes ranging from 25 to 635 mm ID are used to convey corrosive fluids. 

Major polymer applications silicon wafer carriers, pump, pipes, fittings, filtration, tubing, column packing, marine coatings, wear resistant products, coating for hostile environments, automotive weather seals for doors and windows... 

The coefficient of linear expansion of these alloys in the temperature range of 21 to 100°C (70 to 212°F) is 12.2 X lO C (6.8 X 10"V°F), which is slightly above that of cast iron (National Bureau of Standards). Since these loys have practically no elasticity, it is necessary to use expansion joints in relatively short pipe hnes. Connections for flanged pipe, fittings, valves, and pumps are made to 125-lb American Standarci drilling. 

By virtue of its chemical and thermal resistances, borosilicate glass has superior resistance to thermal stresses and shocks, and is used in the manufacture of a variety of items for process plants. Examples are pipe up to 60 cm in diameter and 300 cm long with wall tliicknesses of 2-10 mm, pipe fittings, valves, distillation column sections, spherical and cylindrical vessels up 400-liter capacity, centrifugal pumps with capacities up to 20,000 liters/hr, tubular heat exchangers with heat transfer areas up to 8 m, maximum working pressure up to 275 kN/m, and heat transfer coefficients of 270 kcal/hz/m C [48,49]. 

The discharge head of a pump is the head measured at the discharge nozzle (gauge or absolute), and is composed of the same basic factors previously summarized 1. static head 2. friction losses through pipe, fittings, contractions, expansions, entrances and exits 3. terminal system pressure. 

In burn-out experiments, a test section is part of a loop which may be open or closed, and the question arises as to whether or not any of the loop equipment, such as condensers, heaters, pumps, or pipe fittings, have any significant effect on the burn-out flux. This issue came to prominence at the Boulder Heat Transfer Conference in 1961 with a Russian paper by Aladyev (A4) describing burn-out experiments in which a branch pipe, connecting to a small vessel, was fitted close to the test section inlet. The test section itself was a uniformly heated tube 8 mm in diameter and 16 cm long. The results are reproduced in Fig. 9, and show burn-out flux plotted against exit steam quality. Curve (A) was obtained with the branch vessel filled with cold water,... 

Equipment manufacturers also work to standards to produce standardised designs and size ranges for commonly used items such as electric motors, pumps, pipes and pipe fittings. They will conform to national standards, where they exist, or to those issued by trade associations. It is clearly more economic to produce a limited range of standard sizes than to have to treat each order as a special job. 

The selection of the pump cannot be separated from the design of the complete piping system. The total head required will be the sum of the dynamic head due to friction losses in the piping, fittings, valves and process equipment, and any static head due to differences in elevation. 

Miscellaneous friction losses due to the tanker outlet constriction and the pipe fittings in the inlet piping, are equivalent to 1000 equivalent pipe diameters. The vapour pressure of chlorine at the maximum temperature reached at the pump is 685 kN/m2 and its density and viscosity, 1286 kg/m3 and 0.364 mNm 2s. The pressure in the tanker is 7 bara. 

The biggest use of plastics is for piping sheets are also used for lining vessels and for fabricated ducting and fan casings. Mouldings are used for small items such as, pump impellers, valve parts and pipe fittings. 

As the process model is made more accurate and complicated, you can lose the possibility of obtaining an analytical solution of the optimization problem. For example, if (1) the pressure losses through the pipe fittings and valves are included in the model, (2) the pump investment costs are included as a separate term with a cost exponent (n) that is not equal to 1.0, (3) elevation changes must be taken into account, (4) contained solids are present in the flow, or (5) significant changes in density occur, the optimum diameter will have to be calculated numerically. 

Ithough liquids particularly can be transported by operators carrying buckets, the usual mode of transport of fluids is through pipelines with pumps, blowers, compressors, or ejectors. Those categories of equipment will be considered in this chapter. A few statements will be made at the start about piping, fittings, and valves, although for the most part this is information best... 

Conclusions on pipe-fitting equations. Each of the ft values given in Table 6.1 is the experimental friction factor for that pipe size. This friction factor ft is not to be mistaken for the friction factor for straight pipe f. They are different discrete values to be applied per Eq. (6.11). Ku K2, K3, and KA each represent a different pipe valve or fitting. One could also be a control valve, item 10 in the pipe fitting list. The objective here is to add up all of the fittings expressed as K values and execute Eq. (6.11) to solve the pipe run pressure drop. In summary, this tells how much head hL the pump must put out in order to do the job. 

Economic velocities for turbulent flow (the most common industrially), taking into account piping capital costs (piping, fittings, pumps, etc.) and running costs (pressure drops), are primarily a function of fluid density [A/ fT oc pu2]. Details are given in the literature.4 Order of magnitude economic velocities are ... 

The distribution systen for pure gases and liquids is a classical example of a network system described by large and weakly non-linear systans of algebraic equations. The network comprises pipes, fittings and valves, pumps and compressors, turbines etc., and is subject to boundary conditions at the terminal inlet and outlet points. At these points, the pressure or flow or both are specified. 

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