Nomograph for calculating Reynolds number for compressible flow friction factor
Figure 1. Reynolds number for compressible flow friction factor for clean steel and wrought iron pipe. Figure 1. Reynolds number for compressible flow friction factor for clean steel and wrought iron pipe. The nomograph Figure 1 permits calculation of the Reynolds number for compressible flow and the corresponding friction factor. It is based on the equation Figure 2. Equivalent volume and weight flow rates of compressible fluids. Figure 2. Equivalent volume and weight flow rates of...
Nomograph for calculating Reynolds number for flow of liquids and friction
The nomograph Figure 1 permits calculation of the Re 22 700 qr 50 6 Qr 6 31-W dvr Reynolds number for liquids and the corresponding friction dm dm dm m a factor for dean ed and wrought iron pipe. where Re Reynolds number The Reynolds number is defined as d inside pipe diameter, in. Figure 1. Reynolds number for liquid flow friction factor for clean steel and wrought iron pipe Reproduced by permission, Tech. Paper, 410, Crane Co., copyright 1957 . Figure 1. Reynolds number for liquid flow...
For chart on deflection of horizontal pipe lines see next page
When a horizontal pipeline is supported at intermediate points, sagging of the pipe occurs between these supports, the amount of sag being dependent upon the weight of the pipe, fluid, insulation, and valves or fittings which may be included in the line. If the pipeline is installed with no downward pitch, pockets will be formed in each span in which case condensation may collect if the line is transporting steam. In order to eliminate these pockets, the line must be pitched downward so that...
Rt 1072 T
P absolute pressure, psi psig 14.7 R individual gas constant 10.72 M M molecular weight of gas T temperature, R Sg specific gravity of individual gas relative to air to ratio of gas molecular weight to that of air The above equation and corresponding nomograph Figure 1 can be used to calculate the density or specific volume of gases at low pressures and high temperatures, where the ideal gas law holds. Note that the pressure scale is calibrated in psi gauge so that the correction of 14.7 psi is...
10000 1
Mol flow of ethane 15,000 30.07 499 Mol of ethane 499 4,503 11.08 When a dry gas is saturated with water, it will be necessary to consider the effects of the water on the molecular weight of the mixture. The water will also affect the total mass flow of the mixture. Given Compress 1,000 lbm min dry CO2, which is initially water saturated. MW 44.01, Pinlet 16psia, Tinlet 100 F. Calculate the molecular weight of the mixture and the total mass flow for the required 1,000 lbm min of dry CO2. f...
Reference 1
1. Spink, L. K., The Principles and Practice of Flowmeter Engineering, The Foxboro Company. Streams which transport mixed natural gas liquids require the use of mass measurement to accurately account for the volume of the components which make up the mix. When natural gas liquid components are mixed, non-ideal mixing occurs. Compressibility factors are difficult to determine for mixes. Mass measurement eliminates the effects of non-ideal mixing and the need for compressibility factors. Certain...
Multiphase flow
As stated at the beginning of this chapter, the problems of the simultaneous flow of oil and gas or of oil, gas, and water through one pipe have become increasingly important in oil field production operations. The problems are complex because the properties of two or more fluids must be considered and because of the different patterns of fluid flows, depending upon the flow conditions. These patterns, in any given line, may change as the flow conditions change, and they may be coexistent at...
Estimate engine cooling water requirements
This equation can be used for calculating engine jacket water requirements as well as lube oil cooling water requirements where H Heat dissipation in Btu's per BHP hr. This will vary for different engines where they are available, the manufacturers' values should be used. Otherwise, you will be safe in substituting the following values in the formula For engines with water-cooled exhaust manifolds Engine jacket water 2,200 Btu's per BHP hr. Lube oil cooling water 600 Btu's per BHP hr. For...
Rupture disc sizing
A review of the ASME Section VIII requirements Changes to Section VIII, Division 1 of the ASME Code have impacted the methods used to size pressure relief systems that include rupture discs. The objective of this article is to clarify the sizing methodologies. Kd Coefficient of Discharge This is a unit-less factor used to de-rate the theoretical flowing capacity of a device or system. For rupture discs, this value is defined by the Code as 0.62. Kr Resistance to Flow Factor This is a unit-less...
D
Buoyancy B D 32t 11t2 3 where D outside diameter of pipe, in. t wall thickness of pipe, in. t1 thickness of concrete coating, in. Wc weight of concrete, lb ft3 To find the buoyancy of bare steel and coated pipe in mud in lb ft for coated pipe, where Wm is weight of mud, lb ft3. Example 1. Find the buoyancy of steel pipe with 20-inch OD and 1 2-inch wall thickness in water. What thickness of concrete coating would be required to give this pipe a negative buoyancy of 100lb ft Wc 143 To give this...
Handheld calculator program simplifies dike computations
Calculating height of earthen dikes around above-ground storage can be done easily with a program for a portable calculator Frank E. Hangs, Sovereign Engineering Co., Houston Earthen dikes are widely used all over the world to contain flammable volumes of above-ground storage. They perform two vital functions to prevent loss of fluid into the environ ment and to reduce the likelihood of fire spreading from one tank to another. Sizing dikes by conventional methods is a time-consuming, trial and...
When does a pipeline need revalidation The influence of defect growth rates and
by John F. Kiefner and Patrick H Vieth, Kiefner and Associates, Inc. Worthington, Ohio Buried, high-pressure pipelines are subjected to loads and environmental effects which may cause them to become degraded with the passage of time. All pipeline operators are well aware of this, and the prudent operators have active programs to mitigate deterioration and to remediate defective pipe. The efficiency of an operator's revalidation program can be optimized if the necessary responses can be made...
The hollow bead
The stringer bead defect shown in this sketch is known by several names including the hollow bead, vermicular porosity and wormhole porosity. Its length varies from a fraction of an inch to several inches. Radiography exposes the presence of the problem clearly. Vermicular porosity occurs most readily when welding high silicon pipe generally above .10 silicon. It is aggravated by excessive travel speeds and high currents. Welding the stringer bead with 5 32 4.0 mm' electrode at 130-165 amps DC...
Induced Ac Voltages On Pipelines May Present A Serious Hazard
by Earl L. Kirkpatrick, P.E., ELK Engineering Associates, Inc., Fort Worth, TX, and Kirk Engineering Co., Oneonta, AL The problem of induced AC voltages on pipelines has always been with us. Early pipeline construction consisted of bare steel or cast iron pipe, which was very well grounded. Bell and spigot, mechanical, or dresser-style joint couplings often were used, creating electrically discontinuous pipelines which are less susceptible to AC induction. Although induced AC affects any...
42
Figure 3. Determining two-phase flow pressure drops. Figure 3. Determining two-phase flow pressure drops. From Figure DPtp fL XAPl 0.12 0.16 0.048 0.069 With two pressure drops determined for two flow line pressures for each of the flow rates, lines can be drawn showing pressure drop for different flow line pressures for these two rates Figure 3 . From these two lines relationships can be established for pressure drops for other rates and flow line pressures. The procedure is as follows Start...
Performance calculations for reciprocating compressors
Pd St x N x 3.1416 x D2 4 x 1,728 1 Double acting compressor without a tail rod Pd st x N x 3.1416 x 2D2 -d2 4 x 1,728 2 Double acting compressor with a tail rod Pd st x N x 3.1416 x 2 x D2 - d2 4 x 1,728 Single acting compressor compressing on frame end only Pd st x N x 3.1416 x D2 -d2 4 x 1,728 4 where Pd Cylinder displacement, cuft min St Stroke length, in. N Compressor speed, number of compression strokes min D Cylinder diameter, in. d Piston rod diameter, in. Ev 0.97 - 1 f rp1 k - 1 C - L...
What is the maximum allowable length of unsupported line pipe
For Schedule 40 pipe, the maximum span between supports is given by where S is the span length in feet and P is the actual outside diameter of the pipe in inches. For pipe smaller than 12-inch, the nominal size may be used, and Example. How wide a ditch can be spanned with four-inch line pipe without the use of intermediate supports S 6.6VI5 6.6 X 2.12 13.99 14 feet S 7V4 7 X 2 14 feet Note. The above rule is approximate, but conservative. It does not assume that the pipe is held fixed at...
Commissioning petrochemical pipelines
Pipelines carrying a variety of gaseous and volatile liquid products are extensively employed in today's industry as a safe and efficient means of transportation. New pipelines must be placed into service initially i.e., commissioned , and older lines occasionally are taken out of service in order to perform some desired maintenance and are then recommissioned. Among the reasons for taking a pipeline out of service i.e., decommissioning are hydrostatic testing to recertify or upgrade the...
Lowering a loaded pipeline is a lowcost alternative for constructing new
Lowering an existing line is a dirty little job, but it can have big cost benefits. The line can be lowered while remaining in service with no lost production, and the cost of lowering an existing pipeline section is relatively cheap. No expenses are incurred for new pipe, valves, stopples, and fittings. Construction is much faster than cutting and relocating a pipeline section. Construction of new highways, buildings, airport runways, and other facilities is often planned at locations where...
The fluidpipeequipment interaction
The liquid and the pipe, according to its environment, expand and contract as the surges travel. The pumps, valves and other equipment change the pressures and or flows as the surges reach them. The surges travel at the speed of sound in the fluid-pipe system. The fluid itself is what relays the surge energy to the various pipe sections and the equipment. The fluid, pipe and equipment are inextricably linked and their behavior must be determined by a model that employs simultaneous fluid pipe...
How fast does oil move in a pipeline
Divide the throughput, in barrels per day, by the square of the nominal diameter, in in. divide this result by 100 and subtract 1 from the answer. The answer is the speed of the oil column in miles per hour. Example. A 12-in. line has a throughput of 70,000bpd The oil moves about 4 miles per hour. This rule is rough, but seldom is an exact answer needed for this problem. Greater accuracy can be had by using the true inside diameter of the line in the following formula Q throughput, bpd d inside...
Calculate brake horsepower required to compress gas
The approximate brake horsepower per million cubic ft of gas to be compressed may be obtained from this table. The total brake horsepower required is calculated by multiplying the total million cubic ft of gas compressed. In this estimation, gas volumes are expressed at 14.7psia and60 F, specific gravity as 0.6 and K the ratio of specific heats is 1.27. The suction temperature is assumed as 80 F and interstage temperature as 130 F. The relative humidity of the air equals 100 . Example. What is...
Approximate angle of repose for sloping sides of excavations
Note Clays, SIMs, Loams or Non-Hemorporus Soils Require Shoring and Bracing The presence of ground water requires special treatment. Trench shoring minimum requirements Trench jacks may be used in lieu of, or in combination with cross braces. Shoring is not required in solid rock, hard shale, or hard slag. Where desirable, steel sheet piling and bracing of equal strength may be substituted for wood.
AGA formula
In making field calculations a good rule to follow is the more simple the better. Detailed calculations are difficult to perform under usual field conditions. Another good rule to follow is cool and check. Always allow some time to elapse between calculating and checking. This can be from five minutes to five hours. Even better is to have someone else check your work. Following these rules will eliminate most errors. The gas flow equation as stated in the AGA Committee Report No. 3 is Qh Fb Fr...
Hydrostatic testing for pipelines
After construction of a pipeline is completed, or if pipe has been replaced or relocated, it is necessary to hydrostatically test the pipeline to demonstrate that the pipeline has the strength required to meet the design conditions, and to verify that the pipeline is leak free. The U.S. Federal Safety Regulations for Pipelines require that pipelines used to transport hazardous or highly volatile liquids be tested at a pressure equal to 125 of the maximum allowable operating pressure MAOP for at...
Volume required at test pressure
Vtp Gallons contained in test section at test pressure P, and temperature T F. Fwp Factor to correct for the compressibility of water due to increasing pressure from 0psig to test pressure P, psig Fpp Factor to correct for volume change in pipeline due to pressure increase from 0psig to test pressure P, psig Fpwt Factor to correct for the change in water volume and pipe volume due to change in pipe and water temperature from base of 60 F to pipe and water test temperature, T F. Fwp V 1 - 4.5 x...
Centrifugal compressor performance calculations
Centrifugal compressors are versatile, compact, and generally used in the range of 1,000 to 100,000 inlet cubic ft per minute ICFM for process and pipeline compression applications. Centrifugal compressors can use either a horizontal or a vertical split case. The type of case used will depend on the pressure rating with vertical split casings generally being used for the higher pressure applications. Flow arrangements include straight through, double flow, and side flow configurations....
How to estimate construction costs
Two hand-held calculator programs divide pipeline costs into four component areas right of way, material, labor, and miscellaneous R. D. Green, Energy Center Fellow, University of Pennsylvania Pipeline cost models are numerous and their uncertainty is associated with the degree of generality. Costs vary with distances from manufacturers, terrain, locality, labor costs, season of the year and other variables.1 Hence, it is vital to the interests of construction firms to maintain historical...
Notation
bore diameter of primary device, in. Reynolds number correction factor for steam, vapor, maximum differential or range of differential gauge, in. of water, dry calibrated coefficient of discharge, including velocity of approach at a hypothetical Reynolds number of ratio of specific heats Cp Cr, dimensionless specific weight of flowing conditions, lb ft3
Conclusion
The following factors must be thoroughly considered during the selection process of pulsation dampeners. 1. Maximum design pressure rating of the dampener must be within the operating pressure limit of the system. 2. Liquid port size of the dampener should be equal to the discharge port of the pump or equal to the discharge line size. 3. Dampener should be charged with a neutral gas usually nitrogen to approximately 60 of the mean system pressure. 4. Appendage type dampeners pipe or nipple...
Suppress the surge in the suction and discharge systems of your positive
This article reviews the specific requirements for the selection and sizing of pulsation dampeners to reduce the fluid pressure pulsations generated by positive displacement reciprocating pumps. It includes analyses of the nature of pressure pulsation and explains the advantages of using pulsation dampeners and suction stabilizers. Sizing procedures for dampeners illustrate how their application improves suction and discharge control in reciprocating pumps, reduces pressure pulsations,...
Internal chamfer
It is important to remove any burr or overhang on the inside edge of the pipe after the root face has been machined Figure 6. Recommended joint preparation and typical procedures operate within these tolerances to help ensure good quality welds. Alternate Stringer Bead Procedure AmpeOC - Hot Pass Fills and Stripper Cap Pass Ve 3.2p gt or s 32 4.Op 5 32 4.0 4.8 3 16 4.8 90 120 140 165 4 160 185 160 190 150 180 lt 1 gt Fleetweld 5P , Shield-Arc HYP or 70 suggested depending upon the pipe steel...
Internal undercut
See Figures 1 through 5 for x-rays of the various defects that can cause rejects. Of these, one of the most common and troublesome is internal undercut undercut on the inside of the pipe . This is understandable because it occurs on the blind side and the operator cannot see it happening. Consequently, he cannot immediately do anything to correct it. To make matters worse, he seldom gets a chance to see the x-ray negative or the actual weld itself. All of this makes it difficult for him to...
Underbead cracking
Underbead cracking can be minimized by making repairs with low hydrogen electrodes in a manner that avoids hard weld heat-affected zones. One way to help assure that extremely hard weld zones are not formed during repair welding is to limit repairs to well known carbon equivalent ranges. Unfortunately, chemistries of specific samples needing repairs will seldom be known. Low hydrogen electrodes prevent hydrogen from being present in the welding atmosphere but they do not prevent formation of...
How to bend pipe to fit ditchsags overbends and combination bends
To make straight sags or overbends fit the ditch see drawing add angles of unlike signs, subtract those of like signs. In cases involving either a sag or overbend, in addition to a side-bend, the rule becomes Make the combination bend equal to the largest angle plus 1 3 of the smallest. Slope 10 00' Slope - 1 00' add 11 00' overbend 1 6 00' side-bend left 2 Combination bend 11 V3 x 6 13 00' overbend left. Note This rule gives an error of approximately 1 for a maximum bend of 18.5 Pipe bending...
Size an air receiver for engine starting
Assume that the engine starter requires 16 standard cubic feet per second, that 10 seconds is required for starting and that you want to store enough air in the receiver for three starts. Assume the initial pressure in the receiver is 215psia and the final pressure is 115psia. V Receiver volume, cu. ft. R 53.5 for air T Temperature assumed constant at 520 R M Weight of air required to start the engine based on density of air 0.0763 pounds per cu. ft. P Pressure, pounds sq. ft. M 16 cu. ft. sec....