bluuebunny/crossref_metadata_2025_split huggingface dataset:
Advantages of Flowing Wells through Tubing
Authors: Marsh Hallan N. , Robinson Bruce H. 
Published: June 2014

It is generally believed that the flowing of wells through tubing instead ofcasing results in the conservation of gas. It is further believed that use oftubing prolongs the flowing life of a well and results in greater ultimaterecovery, provided either that there are no adjacent wells, or that anyadjacent wells are similarly operated. Recent experience in the flowing ofBuckbee zone wells at Santa Fe Springs has not only substantiated both of thesebeliefs but has led to the further conclusion that the use of tubing results ina greater cumulative flowing production, even in a highly competitive fieldlike Santa Fe Springs, where the wells concerned are closely offset by wells ofboth the same and other companies flowing through casing. Further, gas-oilratio has been so reduced that greater ultimate recovery can be expected.
In the belief that such would be the case, the majority of the Buckbee zonewells of one company were brought in through tubing, but enough wells wereflowed through casing to form the basis for a comparison. For the purpose ofthis comparison, wells with flow strings 2~-2 or 3-in. dia. are designated astubed wells, while those having flow strings larger than 3-in. dia. aredesignated as untubed wells. Casing used was mostly of 5%-in. dia., theremainder being of 4%-in. dia. There were 15 tubed wells and 8 untubed wellsand they were scattered over the field in such a way that neither group appearsto have any distinct advantage as regards location. Locations of all wellsinvolved in the comparison are shown on Fig. 1. All the Buckbee sand wells ofthe company are included in the average production curves, with the exceptionof eight that were unsatisfactory for reasons other than the method offlowing.

Findings
1. Buckbee sand wells flowing through casing larger than 3 in. had an averagemaximum production rate of 4670 bbl. per day, while wells flowed throughstraight tubing or 3-in. casing had an average maximum production of only 3300bbl. per day. (See Fig. 2.)
Flowing Wells with Small Tubing
Authors: Hawkins R.R. 
Published: June 2014

Properly designed tubing strings make it possible to continue the flowinglife of wells beyond the stage where ordinarily they would be put to pumping.Wells no longer able to flow through 2-in. tubing can be made to producethrough smaller tubing if conditions within the well are carefully studied andcorrectly designed strings are "installed. In this way, pumping expense maybe postponed and in some pools it is within reason that the entire recovery maybe obtained by natural flow if maintenance of pressure is practiced. Infrequenttubing changes would be necessary but their cost would be much less than thatof installing and maintaining pumping equipment.
If small wells are to be made to flow naturally, careful consideration must begiven the actual lifting mechanics within the string, so that fairly accurateknowledge of reservoir conditions, especially pressure, is essential. Wellsproducing between 5 and 25 bbl. daily are classified here as "smallwells."

Exponential Flow
A maximum of the energy contained in the expanding gas must be employed to douseful work if natural flow is to be continued. It is evident that adiabaticexpansion would defeat this purpose, therefore the velocity of the gas must beheld down to a minimum in order that isothermal expansion may be approached. Ofcourse, true isothermal expansion would not be obtainable in an oil well, hencethe use of the term "exponential?. Obviously the closer the approach toisothermal expansion, the more efficient the lift.
Experiments by the U. S. Bureau of Mines have shown that for isothermalexpansion to take place in a gas well where water is being produced, a definiterelationship exists between the depth of the well and the minimum operatingpressure. The latter must be such that the tubing fill-up, if static conditionsprevailed, would be equivalent to 14 per cent of the distance between the topof the fluid inside the tubing and the tubing head.
Recent Development and Use of Bottom-hole Choking
Authors: Ross J.S. 
Published: June 2014

Although the opinion has prevailed for several years that bottomhole chokingunder certain flow conditions should effect an increase in flow efficiencies, the use of bottom-hole chokes until recently has been limited in applicationmainly because of mechanical difficulties encountered in their construction. Within the past year, however, bottom-hole choking, through the development ofa removable type of choke, has been applied successfully under variousconditions of flow in many Mid-Continent fields. The observation of these fieldtests indicates that bottomhole choking, although not applicable to all flowconditions, has an important place in the operation of oil and gas wells.
This paper gives briefly the conclusions drawn from the data obtained from theexperiments with this bottom-hole choke under various flow conditions, and adescription of the choke and its operation.

Purpose of Bottom-hole Choking
Since, in a normal well, the velocity with which the column of gas is movinggenerally has a direct bearing upon the quantity of oil it can lift, probablythe main purpose of bottom-hole choking is to accomplish an increase in thevelocity of this rising column, particularly in the lower portion of the tubingstring. This it does first, by expansion of the free gas accompanying the oil;next, by liberation and expansion of some of the occluded gas normally carriedin the oil to the surface; and lastly, by atomization, which results in a moreintimate and uniform mixture of the oil and gas. It is apparent, then, that ifthis velocity, particularly in the lower portion of the flow string, at a givenrate of production, is inefficiently low, owing either to an insufficientsupply of gas or to excessive surface choking, and slippage takes place, bottom-hole choking should bring about an increased velocity of the gas andhence an increased lifting capacity. But if the velocity of the column of gasat this same rate of production through a surface choke alone is at or above avelocity necessary to lift the oil efficiently, increasing the velocity bybottom-hole choking would probably serve no useful purpose, other than tosteady the flow by the better mixture of oil and gas and to lower deliverypressures.
A Method for Computing Pressure Drop in the Pipe of Flowing Oil Wells
Authors: Nowels K.B. 
Published: June 2014

Data pertaining to pipe line flow for both oil and gas in horizontal ornearly horizontal pipe lines are both extensive and accurate. However, the pipeformulas used to determine pressure drop for flowing fluids (liquids and gases) under conditions of horizontal flow are not generally applicable to flowing oiland/or gas wells. Except for some data developed in small laboratory set-ups, little or no information was available concerning flow of oil and gas mixturesin vertical pipes, when, in 1928, the writer began the development of a methodfor computing pressure drops in the pipes of flowing oil wells, as outlined inthis paper.
In 1929, Uren presented some findings based on laboratory experiments in whichvertical flow of an extremely heavy crude oil was induced by means of airthrough a 2-in. pipe, 41 ft. long. The friction factors derived from theexperiment, as well as values for pressure drop per 100 ft., are not believedsatisfactory in their application to flow problems in the field.
Versluys, also in 1929, presented a mathematical development of the theory offlowing oil wells, and in 1930, gave a companion paper setting forth someprinciples governing the choice of length and diameter of tubing in oil wells. Since the termination of the study presented in this paper, another valuablecontribution pertaining to the problem of vertical flow was made by Moore and Wilde.
Although there were writings dealing with the principles of the gas-lift, asearch of the available literature indicated that specific information onvertical flow was lacking with the exception of the writings of Uren, Versluys, and Moore and Wilde, to which reference has been made.
Petroleum Stabilization in 1932
Authors: Oliver Earl 
Published: June 2014

Superficial observation of the petroleum stabilization movement in 1932 isdisappointing. Threatened overproduction persisted; waste continued; prorationwas violated; gasoline taxes were evaded; and, as a consequence, chaosthreatened the industry as the year drew to a close.
However, comparison of the movement in 1932 with its beginning a few years ago, and analyses of those influences that promote its growth as well as those whichretard it, disclose some reasons for encouragement.
Stabilization, as we see it, is not merely a mechanical engineering problem. Itinvolves social engineering. By which we do not mean it is possible, or evendesirable, to change the nature of men, but rather that it is possible to setup procedure that will avoid causing them to clash. It comprehendsconsideration of physical objects that is clearly within the field of theengineer, but it considers them only in relation to their distribution, utilization and control in harmony with philosophies that motivate men andshape current conceptions of right and wrong or of justice and injustice ifthose terms be deemed more acceptable.
Stabilization cannot be effected without utilizing the knowledge of theengineer, but neither can it be effected without utilizing more than comeswithin his traditional field of activity. In discussing the problem herein weshall endeavor to treat it briefly from that consolidated viewpoint.
Rapid fluctuations in supply have characterized the oil industry from itsbeginning; yet only within the past ten years has an understanding begun todevelop regarding the extent of waste-the degree of dissipation of naturalresources-that attends the operation of the industry under the practices andlaws which control it in the United States. The extent and regrettableconsequences of those wastes, their underlying causes and the ease with whichthey could be prevented are not yet generally understood even within theindustry.

Producing Tomorrow's Oil Today
The interests detrimentally affected by these economic evils are vastly greaterthan the mere 'welfare of the oil industry.
Recoverable Oil and Gas Content of Land as Suitable Standard of Each Owner's Rights in Pool
Authors: Griswold E.H. 
Published: June 2014

The many complexities arising from our present oil pool proration systemsemphasize the need for a suitable standard of property rights. Attempts atconservation and unitization agreements have frequently failed because of thelack of such a standard.
The necessity of reducing production to consumption has caused umpires, committees, commissions and other governing bodies to allocate the productionof flush fields among the respective owners. The methods of allocation varywidely and conservation of underground reserves is frequently neglected ormisused.
Critical economic conditions increase, rather than modify, competitive methods.In some fields we have irregular and uneconomically close well spacing. Manyoperators drill unreasonably large holes, take excessive sand penetrations orleave their wells untubed in order to secure higher potential open-flow teststhan their offsets. All of these practices result in economic waste andfrequently damage to the pool.
Regardless of our agreement with the fundamental principles of proration orunitization, both are actual necessities in many of our present economicsituations, and we are in urgent need of a suitable standard of rights tofacilitate and simplify their operation.
The problems pertinent to unit management are simple and of daily use in manypartnership enterprises, but the problems of fair and proper division ofproduction under either proration or unitization are, as yet, subject tocontroversy. The rights of respective owners must be ascertained andstandardized before we can eliminate wasteful practices and still preserveconstructive competition in our industry.

Valuation of tracts
In a recent unitization conference it was found that each participant had adifferent basis for calculating the relative values of tracts. Some of theseassumptions were as follows:Unrestricted open-flow operation to abandonment.Current proration system to abandonment.
Production Engineering in 1932
Authors: Stephenson Eugene A. 
Published: June 2014

In spite of tremendous handicaps notable advances in production engineeringhave been achieved during 1932. The technique of deep well drilling hascontinued to progress, notably in California and at Big Lake, Texas. In thelatter field a method has been devised by which two grades of oil in contactwith each other are produced without intermingling. In rig design manyimprovements have been made whose objective is to facilitate deep drilling withreduced power losses and increased life of the equipment. Flush joint casingand drill pipe have been improved further, careful tests indicating that thedrilling time can be reduced by from 5 to 20 per cent where flush-joint pipe isused.
Slow-speed pumping has come into wider use, with further increases in over-allefficiencies. A number of improved well pumps also have been developed and arebeing tested. One of the most important of these is a positive displacementpump of the rotary type, directly connected to an electric motor placed in thebottom of the hole, and adaptable to various sizes of tubing and casing.
In some localities the trend is towards the replacement of electric motors andlarge-cylinder engines by multiple-cylinder gas engines.
Experiments have been conducted and critical analyses made of flow conditionsin wells equipped with various styles of tubing which give promise that tubingmay be designed to fit individual well conditions. In those wells producing atless than maximum capacity, the gas-oil ratio has been shown to depend on therate rather than on the method of production, or the design of equipment.
Important factors in the design of screened pipe have been carefully analyzedand made the basis of a method for determining the required mesh.
Remarkable progress has been made in the use of subsurface pressure data.
The Killing and Well History of Milham Elliott No. 1 and Continental Elliott 12-8 Wells on the North Dome of Kettleman Hills, California
Authors: Silent Roy , Rousselot N.A. 
Published: June 2014

The first producing wells completed in the Kettleman Hills area werenoteworthy for their high gas-oil ratios. As a result they became the object ofcriticism, and controversies arose based on their alleged lack of gasconservation. Ultimately protracted hearings ensued in the District Court ofthe area, and diverse rulings and subsequent modifications have been handeddown affecting the permissible gas-oil ratios. When the Kettleman North DomeAssociation was formed in April, 1931, and the control of the major portion of the North Dome area vested therein, it was decided to produce only those wellswhich had a relatively low gas-oil ratio.
Among the wells having the highest gas-oil ratio were the Milham Elliott No. 1(the discovery well) and the Continental Elliott 12–8, drilled as an offset toit. Under the numbering system adopted by the Kettleman North Dome Association, these wells are now known as 88–2P and 1–12P, respectively.
Milham Elliott No.1 was originally drilled to 7236 ft., then redrilled to 7108ft. The upper portion of the Temblor Horizon produces with a very large gas-oilratio; production which actually consists of light crude oil with an'accompanying large volume of gas. Little was known as to the location of theTemblor formation at that time but it is now generally accepted that its topwas encountered at 6180 ft., giving 928 ft. of penetration. Initial productionwas estimated at 4000 bbl. of oil and 80 to 90 million cubic feet of gas perday, giving a gas-oil ratio in excess of 20,000 cu. ft. of gas per bbl. of oil.This ultimately increased to a ratio of about 48,000 at the time the well waskilled when it was producing about 1100 bbl. of oil and 52 million cubic feetof gas, with a flow pressure of 1200 pounds.
The Continental Elliott 12–8 was drilled to a depth of 6876 ft. with the top ofthe Temblor at 6100, giving a penetration of 776 ft.
Proration of an Oil Field Based on Uniform Allowable Gas Production
Authors: Barnes R.M. , Bell A.H. 
Published: June 2014

The ideas set forth in this paper are proposed for consideration anddiscussion as the result of recent study of various plans for control andproration of gas and oil production from Kettleman North Dome oil field. Theywould be applicable to any oil field during its flush production stage. Theproblems of development and proration are so intimately connected in Kettlemanhills and in many other flush fields that they have both been covered in thispaper.
Many are of the opinion that Kettleman North Dome oil field should beconsidered as containing only one zone to its present total penetratedthickness of nearly 1500 ft., and that the hydrocarbon content of this zonegradually changes from dark and relatively low-gravity oil with relatively lowgas-oil ratios on the flanks and plunges to mostly light-colored andhigh-gravity oil with high gas-oil ratios in the higher structural positions, somewhat according to the idealized section shown in Fig. 1. At least the lower400 ft. contains dark oil in the higher structural positions.
Mechanics of Water Movement in Natural and Artificial Flooding of Oil Sands
Authors: Nowels K.B. 
Published: June 2014

The attainment of efficient flooding to a large extent depends upon aknowledge of fluid movement through porous media and the pressures used incontrolling this movement, Little has been understood concerning thefundamental principles involved in the forced drive of water-flooding and anattempt will be made to present some data which may be of interest.
Considerable data and technical information pertaining to natural andartificial water-flooding have been presented in the past by Torrey, Umpleby, Fettke, Panyity and others. Their papers have thoroughly covered thedescription of past and present-day methods of oil recovery by flooding in theBradford field, especially an article by Torrey in the Petroleum EngineeringHandbook. A bibliography of papers devoted to water-flooding, published in Mr. Torrey's article, is appended to this paper. No attempt has been made, therefore, to describe the installations and procedure necessary in flooding, thus permitting the writer to deal exclusively with the mechanics of watermovement in flooding operations and its relationship to well spacing.
Artificial water-flooding will probably always be the most successful in oilfields described by Herold as being under "capillary control" and willprobably be useless in fields naturally under hydraulic or volumetric control.The natural water drive in an oil field under either of these two controls maygive efficient recoveries, as a result of the regulated encroachment of edgewater. Such a "natural flood" resulting from the influence of edgewater must not be confused with the term as used in this paper, however. Anyreference to "natural flood" will here refer to the old method offlooding formerly used in the Bradford field. This was discovered largely byaccident and utilized the hydrostatic pressure created by a column of waterstanding in a watered-out oil well in forcing the oil to an adjacent producingwell.
Development of Hydrogen Porosimeter
Authors: Coberly C.J. , Stevens A.B. 
Published: June 2014

The absolute porosity of a rock or sand may be defined as the volume of the inter particle space expressed as a percentage of the total rock volume. The effective porosity as contrasted with the absolute porosity is the volume of the interparticle spaces which intercommunicate with passages of sufficientsize to permit the entrance or recovery of gas or oil, also expressed as apercentage of the total rock volume. A knowledge of effective porosity is ofprime importance in estimating the ultimate recovery to be expected from oiland gas-bearing formations.
The determination of the effective porosity of a rock includes the measurementof two values:the volume of the rock as a whole, andthe volume of thegrains and sealed pore space.
This paper deals with a new apparatus which hasbeen called a "hydrogen porosimeter" for determining the volume of thegrains and the sealed pore space. This volume is determined by means of thepressure relations established in the instrument by the introduction of a knownquantity of hydrogen.

The Hydrogen Porosimeter
The apparatus used in this work consists of an upper chamber for measuring thegas, a lower chamber for holding the sample to be tested, a gage for measuringthe pressures, a tank of hydrogen, and the necessary connections. (Figs. 1 and 2.)
Of the several gases that might be used for this work, hydrogen has been chosenfor three reasons:it deviates less from the gas laws than most gases;it readily penetrates the sample;it is absorbed less than most gases bythe solids and liquids with which it may come in contact.

Method of Operation
After placing the sample to be tested in the lower chamber, the apparatus isthoroughly flushed with hydrogen to remove all air from the system, which isthen brought to atmospheric pressure The valve connecting the two chambers isnext closed and the pressure in the upper chamber is brought up to a pressureby admitting gas from the tank.
Effect of Gas Withdrawal upon Reservoir Fluids
Authors: Lindsly Ben E. 
Published: June 2014

The withdrawal of gas and/or oil in appreciable quantity from a natural oilreservoir causes the pressure within the reservoir to diminish, and if the oilis completely saturated with gas, this dissolved gas begins to evolve fromsolution. The liberation of gas from solution in oil causes the oil to changein several ways, the principal changes being:reduction in volume or "shrinkage";increase in specific gravity (decrease in degrees A.P.I.);decrease of energy in the oil;increased viscosity;increased surface tension.
As the writer's investigations have been concerned more with the first threeitems than with changes in viscosity and surface tension the followingdiscussion relates particularly to the volumetric shrinkage of the oil, to theincreased specific gravity, and to the decreased energy in the oil, each causedby the liberation of dissolved gas.
One of the most surprising facts that have developed in the study ofhigh-pressure well-head and" bottom-hole" samples is the greatreduction in volume that occurs in some oils when the naturally dissolved gasis liberated. High-pressure samples taken from well heads in the Oklahoma City, Kettleman Hills and Ventura, Calif., fields decreased in volume from 11.2 to40.5 per cent when the dissolved gas was liberated in reducing the pressure onthe sample to atmospheric.
The amount of shrinkage an oil undergoes when gas is liberated depends upon thequantity of gas liberated and also upon its composition. A given volume of theheavier gases, propane and butane for example, will occupy more space in theoil than an equal volume of methane. The reason for this probably is that themolecules of the heavier gases are larger than those of the lighter gases. Whengases are not in solution, and particularly when they are at low pressures, thedistance between the gas molecules is so much greater than the dimensions ofthe molecules themselves that the mere size of the molecules has little effectupon the space occupied by the gas. Avogadro's hypothesis, which in effectstates that all gases under the same conditions have the same number ofmolecules per unit volume, relates to this phenomenon.