Pipe enlargement

CALCULATE THE K VALUES OF THE SUDDEN CHANGES IN PIPE ENLARGEMENT/REDUCTION WITH TAPERED ANGLES OR WITHOUT TAPERED ANGLES. 

Sudden enlargement losses. If the cross section of a pipe enlarges very gradually, very little or no extra losses are incurred. If the change is sudden, it results in additional losses... 

Trumpet-shaped enlargements for turbulent flow designed for constant decrease in velocity head per unit length were found by Gibson (ibid., p. 95) to give 20 to 60 percent less friclional loss than straight taper pipes of the same length. 

There is a sudden reduction in the suction between the tank and the piping. There is an eccentric 6-to-4 reducer between the suction pipe and the pump. There is a eoneentrie 3-to-4 inereascr from the pump back into the piping, and a sudden enlargement going into the discharge tank. The formula is ... 

The velocity of pumping has to be reduced. It may be done by exchanging the pipes for bigger diameters, or by insetting at least an additional enlarged sector of pipe which acts as a relaxation tank and allows self-relaxation of the generated current. 

For sudden enlargements in a pipe system when there is an abrupt change from a smaller pipe flowing into a larger pipe, the resistance coefficient, K, is given by ... 

For sudden pipe system contractions as represented in Figure 2-12A through 2-16, the values of the resistance coefficient, K, can be read from the charts. For more details for various angles of enlargements and contractions, see References [3] and [2]. 

The K coefficient values for each of the items of pipe, bends, valves, fittings, contractions, enlargements, entrance/exits into/from vessels are additive as long as they are on the same size basis (see Table 2-2 and Figures 2-12A through 2-16). Thus the resistance equation is applicable to calculate the head or pressure loss through the specific system when the combined Rvalue is used. 

P = ratio of small to large diameter orifices and nozzles and contractions or enlargements in pipes... 

Figure 2-38C. Critical Pressure Ratio, r, for compressible flow through nozzles and venturi tubes. By permission, Crane Co., Technical Paper 410, 1957. Also see 1976 edition. See note at Figure 2-18 explaining details of data source for chart. Note P = psia p= ratio of small-to-large diameter in orifices and nozzles, and contractions or enlargements in pipes.

P = Ratio of imernal diameter of smaller to large pipe sizes, or for orifices or nozzles, contractions or enlargements... 

Some situations bring into question the necessity of a surge drum in the system. This hecomes more evident in the low flow rate, high compression ratio units in which the drum is calculated to he only slighdy larger than the usual pipe size. In some of these cases, it has heen found satisfactory to enlarge the pipe size and eliminate the drum. Each system must he carefully evaluated as generalities cannot solve the variety of situations. 

To maintain the BSR at less than 5.5, the string of drill collars must frequently be composed of different sizes. For severe drilling conditions (hole enlargement, corrosive environment, hard formations), reduction of the BSR to 3.5 helps to reduce frequency of drill pipe failure. 

In 1929, an international commission, the Commission Mixte Internationale pour les experiences relatives a la protection des lignes de telecommunication et des canalisations souterraines (C.M.I.), was enlarged and its scope extended for the purpose of making experimental studies concerning the corrosion of pipes and cables. The C.M.I. membership was composed of international technical experts from learned bodies, research laboratories and manufacturers of electrical equipment, and representatives of authori-... 

Angles of divergence or convergence in enlargements or contractions in pipe systems, degrees... 

Venting, dusts, (deflagration), nomograph, API, 514-520 Relief valves, 400 Code requirements, 415, 420 Installation, 422, 429-434 Safety-relief, 400 Relieving pressure, 411-417 Resistance coefficient, K, (flow), 71, 72 Flow coefficient, Q, 81, 83 Pipe sizing, 83, 84, 86 Sudden contraction, 80 Sudden enlargement, 80 Tables/charts, 73-76, 77, 78-80 Valves, 81... 

Friction losses occurring as a result of a sudden enlargement or contraction in the cross-section of the pipe, and the resistance of various standard pipe fittings, are now considered. 

For the fluicj flowing as shown in Figure 3.15, from section 1 (the pressure just inside the enlargement is found to be equal to that at the end of the smaller pipe) to section 2, the net force = the rate of change of momentum, or ... 

The loss can be substantially reduced if a tapering enlarging section is used. For a circular pipe, the optimum angle of taper is about 7° and for a rectangular duct it is about 11°. 

Water flows at 7.2 m- /h through a sudden enlargement from a 40 mm to a 50 mm diameter pipe. What is the loss in head ... 

For flow at right angles to the axes of the tubes, the cross-sectional area is continually changing, and the problem may be treated as one involving a series of sudden enlargements and sudden contractions. Thus the friction loss would be expected to be directly proportional to the number of banks of pipes j in the direction of flow and to the kinetic energy of the fluid. The pressure drop - APf may be written as ... 

Any obstruction to flow will generate turbulence and cause a pressure drop. So, pipe fittings, such as bends, elbows, reducing or enlargement sections, and tee junctions, will increase the pressure drop in a pipeline. 

After extensive research and several tests, the option selected was recycling hypochlorite to the feed brine of the electrolysis cells. For this purpose, hypochlorite feed pipes were manufactured and the hydrochloric acid feed capacity to the brine degassing tanks was enlarged. 

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