CA1053092A - Method of providing wire strand from a strand production facility - Google Patents

Abstract

Abstract of the Disclosure A method of making a series of wire strand sizes bracketing the most frequently requested strand sizes from a limited number of predetermined wire sizes by combining the stock wires together into a predetermined pattern to make any required strand size in the series. By producing wire strands in accordance with the invention the inventory of wire normally kept on hand in a production facility is decreased and the promptness with which orders for strands may be supplied is increased.

Description

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Background of the Invention This invention relates to wire strand and cable and more particularly to the expedltious production of various strand sizes from a production facility with a minimum of excess inventory or wire.
In the normal production facility for producing wire strand it is customary, when an order is received for a length of strand, to immediately order the requisite wire for production of the strand. Most strand is ordered by size, such as one and three quarters inch strandg two inch strand, and so forth. Since there is always a possibility of receiving a length of wire having a defect in it or in damaging a portion of a wire while stranding it in a stranding machine, it is customary to order more ~
wire than is actually needed for the length of strand for which an order `
has been received. The specifications for some strand products such as boom pendants and the like forbid the use of welds in the component wires :

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and thus if a wire should break during stranding into a strand the entire length of wire must be discarded at least for the particular order being fabricated. Furthermore, since there are many different sizes of strand and many manners in which wires of various sizes may be combined together to make a strand o a given size, it has been customary for the wire of a par~icular size suited for each specific strand to be especially ordered for each strand. Special order wire must, of course, be especially made and it is necessary to fit such orders in between other orders for wire so that often there is a significant and e~en a considerable time interval involved in ~-supplying the wire. This is true whether the wire in question is to be supplied from another shop of the same production facility or whether it has to be ordered from an outside source, After the strand has been manufactured it is often the case if the fabrication has gone well that a considerable length of excess wire is left over. This wire is then held in inventory until another use, usually in the making of a strand of ~-the same typel is found for the wire. Since there are a number of different sizes of wire used in various strands, it is frequently some time before the same size and type of wire -~
is required again. The amount of wire held in inventory thus tends to become greater and greater, often building up to completely impractical amounts. It is not unusual for the wire inventory in a strand and/or wire rope shop to amount to three or four hundred tons or even more. All this excess wire held in inventory is a drain on working capital since it ties up money in unused wire supply and also is a waste both of storage space and of the labor necessary to keep track of wire in inventory and to find inventory stock when it is ~ ;

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required for the ma~ing of a new order of strand.
Occasionally when difficulties are encountered durin~ the fabrica- ~;
tion of the strand from the l~ire clue to breakage of or defects in the wire, particularly where welds are not allowed in the wire in a particular product, it may result that insufficient ectra wire i5 initially orderecl to complete the order and fabrication of the orcler must be held up until additional wire is especially reordered.
The invention is a method of e~cpeditlously providing wire strand in a predetermined range of regularly increasing strand sizes with regular intervals therebetween from a wire strand production facility comprising:
~a) stoc~ing a supply of wire in two sizes wherein the first wire is a pre- `
determined size smaller than the second wire equal to the predetermined intervals between the wire strand slzesJ and is three-quarters of the diameter of the second wire, (b) fabricating an order of strand from said predetermined range of stock sizes of strand by:
~1) closing the strand in a stranding machine using one of the two wire sizes for the center wire of the strand, and

(2) building up the remainder of the strand from a combination of operations in ~iire stranding apparatus wherein each operation is comprised of one or the other of the sizes of wires to provide a strand within the predetermined range of a series of sizes by providing a sequence of operations of wires in accordance with the following ; sequence of operations to attain any desired size of wire strand con-forming to the predetermined series of wire strand sizes: ;
Diameter Construction unity first wire size center + 1 operation of first wire size ~-unity + 1 interval second wire size center ~ 1 operation of first wire size ` unity + 2 intervals first wire size center ~ 1 operation of second wire size unity + 3 intervals second wire size center + 1 operation c~f seconcl wire size ; 30 unity + 4 intervals

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Diametcr Construction :
unity + 5 intervals unity ~ 6 intervals first wire size center ~ 2 operations of first wire size unity ~ 7 intervals second wire size center -~ 2 operations of irst wire size unity ~ 8 intervals first wire size center ~ 1 operation of first wire size and one operation of second wire size unity + 9 intervals second wire size center + 1 operation of first wire size and 1 operation of second wire size unity + 10 intervals first wire size center + 2 operations of second wire size unity ~ 11 intervals second wire size center + 2 operations of second wire si7e unity ~ 12 intervals first wire size center ~ 3 operations of first wire size unity + 13 intervals second wire size center ~ 3 operations of first wire size unity ~ 14 intervals ~ first wire size center + 2 operations of first wire size + 1 operation of second wire size etc.
and wherein the center wire size alternates between said first wire and said second wire size beginning with the use of the first wire size in a strand having a diameter of unity and the unity plus four and unity plus five strand sizes of the series do not exist.
The present invention also provides a method of expeditiously providing wire strand in a predetermined range of regularly increasing strand sizes with regular intervals therebetween from a wire production facility comprising: (a) stocking a supply of wire in two sizes wherein the first -wire is a predetermined size smaller than the second wire equal to the predetermined intervals between the wire sizes and is three-quarters of the diameter of the second wire, (b) fabricating an order of strand Erom said predetermined range of stock sizes of strand by:
(1) closing the strand in a stranding ~ac1line using one of the two wire sizes for the center wire of the strand, :, .
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~le present invention also provides a method of e~peditiousl~
providins wire strand in a predetcrmined ran~e of increasing strand sizes with re~ular size intervals therebetween from a wire strand production facility comprising: ~a) stocking a supply of wire in a first principal wire size and a second principal wire size wherein the first wire is a predetermined size smaller than the second wire substantially equal to the predetermined interval between wire strand sizes and is substantially three-quarters of the diameter of the second wire size, ~b) fabricating an order of strand from said predetermined range of stock sizes of strand by: -(1) closing the strand in a stranding machine using~one of the two wire sizes for the center wire of the strand, and (2) building up the remainder of the strand from a combination of operations wherein each operation is comprised of wires composed of one of the wire sizes in a sequence such that:
(i) the first strand size of the series is comprised of a first center wire and an operation of first wires laid thereabout, ~ii) the second strand size is comprised of a second center wire ; and an operation of first wires laid thereabout, (iii) the third strand size is comprised of a first center wire ; . .
and an operation of second wireslaid thereabout, (iv) the fourth strand size is comprised of a second center wire and an operation of second wires laid thereabout, ., :: :
. (v) the fifth and si~th strand sizes are non-e~istent, : ::
`` (vi) the seventh strand size is comprised of a first center wire and two operations of first wires laid thereabout (vii) the eighth strand size is comprised of a second center wire and two opcrations of first wires laid thereabout, (viii) the ninth strancl size is comprised of a first center ~ire and onc operation of first wires and onc operation of second wires -4a-3~92 .', :': ' laid thereabout, (i~) the tenth strand size is comprisecl o~ a second center wire and one operation of first wires and one operation of second wires laid thereabout, (x) the eleventh strand size is compriscd of a first center wire and two operations of second wires laid thereabout, txi) the t~elfth strand is comprised of a second center wire and two operations of second wires laid thereabout, (xii) the thirteenth strand is comprised of a first center wire and three operations of first wires laid thereabout, (xiii) the fourteenth strand is comprised of a second center wire and three operatiors of first wires laid thereabout, (~civ) the fifteenth strand is comprised of a first center wire and one operation of second wires and one operation of first wires laid thereabout, and (xv) each succeeding strand in the series is made by alternating the size o-f the center wir0 between the irst and second wire sizes for each successive strand in the series and each time the center wire changes to a first wire changing one of the outer operations of the strand to a second wire size provided further that each time the center wire and all the outer operations of -the strand become second wires the ne~t s~rand size in the series will be comprised in part of a first center wire and three operations of first wires laid thereabout.
The foregoing difficulties and problems associated with prior art methods of producing wire strand have now been obviated by the present invention. The present inventor has discovered that, due to the peculiarities ; of wire sizes and particularly the unique relationship whicll exists between certain combinations of two wire sizes such as for instance t}-ree-si~teenths and one~quarter inch nominal diameter wire~ it is possible to make a whole series of stocli type wire strands having sizc increments of o~ly ~ractions of an inch or centimeter between strancls and such that a suitable strand can -.lb~
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only a limited number of wire sizes. In this manner only a limited amount of wire need be kept in inventory since any e~cess wire left over from the production of one strand size can be easily applied to the production of anotl~or strand size. In addition, the limited number of stock sizes of wire can be more quickly supplied from a wire production facility. Alter-natively, it is a simple matter to maintain a small permanent inventory of the limited number o-f stock wire sizes required to make strand according to the present invention so that each order of strand can be made up as ~ -soon as a stranding machine is available and without having to order the reouisite ~Jire from a wire production facility.

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As the stock wire is used immediatel~ from inventory, it is a simple matter for a stock clerk to reorder as necessary to maintain the desired level of inventory. Recordering can be accomplished either as wire stock is actually used or as the order for strand is received, but before the strand on order is actually fabrlcated. In either case no waiting is required for the arrival of the requisite wire before the order for the strand can be fulfilled by stranding the order, yet the inventory level can be kept low, avoiding the tying up of capital in excess inventory, possible deterioration of the wire held in inventory and the inevitable costs and inefficiencies inherent in the -~
maintenance of a large inventory of many different sizes of wires. Further-more~ in the event that difficulty is encountered in stranding a product with the wire ordered, additional wire can usually be drawn from the inventory of stock wire sizes to complete the order without delay.
The single Figure is a table illustrating the series of strands which can be made from two wire sizes according to one variation of the inven-tion.
In accordance with the present invention a conventional stranding apparatus for the stranding of wire strand is used to strand orders for strand in a predetermined series of strand sizes having constant size inter-vals be~ween the nominal sizes of strand to be produced.
The present inventor has devised a system of supplying wire strand from a production facility, that is to say a shop in which the strand is stranded in any type of suitable production stranding equipment known to those skilled in the stranding art, in which only a limited number, i.e. two wire sizes need be used in order to form an entire series of strands having uniform predetermined small intervals in size between the strands of the series. One convenient size interval to use is one-eighth of an inch.
The adoption of one-eighth inch intervals between strand sizes will result in a series of readily producible strands which will fulfill the . ~, ~: _ 5a ~
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requirements of most strand users for different size strands. `
In the production of wire strands in accordance w~th the present invention it is initially necessary to determine the smallest size strand which it will be desired to make in the series of predetermined strand sizes and also the size intcrval which it is desired to have between the uniformly increasing strand sizes in the series. The smallest strand size to be pro-duced will be herein referred to as a strand having a diameter of "unity".
Every strand in the series is then based upon the unity size strand.
The method of making a predetermined strand series according to the present invention may be used to produce strand made with a small interval between stock strand sizes of the predetermined series of strands.
The method is accomplished by stocking just two stock wire sizes, the first `~
wire size being a predetermined size smaller than the second wire size.
The predetermined size by which the wires differ in diameter is equal to the interval which it is desired to have between the strand sizes in the system of strands. The smaller of the two wires is three-quarter of the diameter of the larger of the two stock wires used in the series.
In the wire strand system of the inVeTItion an initial wire core having a diameter of unity will be constructed by stranding a first strand composed of a center wire of the first diameter having an operation of first diameter wires stranded about it. According to the invention a strand having a diameter of unity plus one interval will then be composed of `-a center wire of the second or larger stock wire size (which is one interval larger than the first wire size) with an outer operation or layer of the first ~or smaller) wire size~ A strand having a diameter of unity plus two intervals will then be constructed from a center wire of the first or smaller wire size plus one operation or layer of the second or larger wire size.
By decreasing the single center wire size one interval and increasing the outer wire size one interval, the effective diameter of the strand is in-creased one full interval since there are two outer wires across the , ~, - 6 -- . - , :,, . ............................................. . . :-~.

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diameter of the strand but only one center wire across the diamter of the strand. Thus one interval is subtracted as two intervals are added to the diameter resulting in a net increment in diameter of one interval.
The next strand diameter of unity plus three intervals is constructed of a center wire of the second or larger size plus an outer operation or layer of second diameter wires. [t ~ill be recognized that by increasing the size of the center wire one interval the overall diameter of the strand is increased by one interval.

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The next two lntervals of strand dia~te~, i.e. unity plus four and unlty plus flve, are, because of the peculiarities of wire sizes and packing arrangementsJ not manufacturable by the use of the two primary stock wire sizes and thus do not exist in the predetermined system of strands according to the inventlon. A strand having a diameter of unity plus six intervals, however, would be composed of a center comprised ;~
of a first or smaller center wire plus two operations or layers of first wire size stranded consecutively about the center wlre. A strand of unity plus seven would then be constructed by using a center wire composed of second stock size wire, or the larger wire size, plus the same two operations or layers of first, or smaller, wire size stranded about the center wire thus effectively increasing the diameter of the strand by one interval of diameter. A strand of unity plus eight diame~ers would be constructed by using a first or smaller center wire plus one operation or layer of first or smaller wire size and one operation of second or larger wire size effecting a net increment of diameter of the strand of one interval. A strand ~ ;
of unity plus nine intervals would be comprised of a center wire of the second or larger stock wire size plus one second ;
wire siz~ and one first wire size operation or layer about the center of the strand. A strand of unity plus ten intervals would be composed of a first wire center and two outer operations of second, or larger, stock wire giving a net incremen~ again of one interval in diameter for the overall strand. A strand of unity plus eleven would be composed of a second or larger wire center plus two operations of second wire size. A strand ., ::

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having a diameter, on the o~her hand, of unity pl~ twelve lntervals would have a center wire of the flrst wire slze plu5 three outer operations of first wire slze. Thus by subtracting one interval from the size of ~he center wire and two intervals each from the size of the two outer layers of the strand, or a total decrease of five intervals, and at the same time adding one extra layer of first diameter wires, there is a net increase of one interval to the outside diameter of the strand.
The next strand size, namely unity plus thirteen intervals, is composed of a center wire composed of a second or larger size wire plus three operations or layers of first size wire~ A strand having a diameter of unity plus fourteen intervals on the other hand is composed of a first wire size center wire plus two operations of first wire size and one operation or layer of second wire size. The strand series can be almost indefinitely extended beyond this point by alternatlng the size of the center wire between the first wire size and the second wire size while simultaneously, each time -~
the center wire returns to the smaller first wire size, increasing ~he size of the wires in one of the outer layers of the strand. When all of the layers plus the center wire are composed of second wire sizes then the size of all the wires in the first two layers and the center wire of the strand are returned to the first or smaller wire size and an additional layer of outer first or smaller wires is added to the outside of the strand. --One very satisfactory embodiment of the invention using two sizes of stock wires in accordance wlth the above is one , _g _ .

in which the flrst smaller size wlre is .188 inches in dlameter and the second larger size wlre i9 .250 inches in dlameter.
I~ is convenient to designate the center wire of a strand of unlty as the flrst wire of the particular series. The initlal center wire in a strand of unlty is the smaller of the two wires. It is usually advantageous in productlon time to usa the largest sizes of wire possible or permissible while still maintaining the necessary properties of the wire. A .188 inch wire, is, furthermore, just seventy-five percent of the diameter of the .250 inch wire making the wire geometry proper for the fabrication of the strands of the invention. The use of larger rather than smaller wires in a strand is, other things being equal, desirable in order to have as few wires as possible in the strand in order to cut down on the operations necessary to both make the wire and to strand or lay the wire into a wire strand. The addition of a few extra wires in the strand may often be enough to require passage of the strand through another operation or pass in the stranding apparatus if the capacity of the strander is exceeded by the number of wires in the strand. Each extra operation means additional handling and time for production with resultant increase in manufacturing expense.
A chart may be constructed to illustrate the use of a first wire size of .188 inches and a second wirè size of .250 inches in the present invention as described above with respect to the second principal method of the invention. Such a chart or table is shown in the single FIGURE
attached hereto. The table shown in the FIGURE is designed to quickly indicate the general construction of wire strands using the .188 inch and .250 inch wires in accordance with the invention.
This chPrt or table is read down along the left edge to find the size of strand which will be made by various numbers of .250 inch wires across the diameter of the strand and along the top edge to find the size or diameter of strand which will be made by various numbers of .188 inch wires across the diameter of the strand. Strands composed of mixtures , .

of the two ~ire sizes can be found ln th~ body of the chart.
Both the nominal size in inches and fractlon~ of an lnch and tho actual theoretical size in whole and decimal parts of an inch are shown in the body of the chart. When ordering a strand the size o~ the strand is found in the body of the chart and the number of layers o~ both .188 inch and.250 inch wires are read off from the top and side of the chart respectively. Lines pass through non-existent strand constructions. The diagonal lines also enclose within their boundaries all of the strands of the series constructed of the same number of wires. The total nw~er of wires in each respective strand can be read off the top and the side of the table respectively. The center wire diameter is always the odd nurnber at the edge of the chart corresponding to the coordinates of the strand diameter and the number at the other side of the chart is always an even number indicating full outer layers of wires about the strand each of which layers contributes two wires to the strand diameter. The sequence of progressively larger nuTnbers of wires can be read off the chart from the top and the left. The sequence of strand sizes progressing from the smallest to the largest size can be read consecutively along the diagonals progressing from the :
top down across the page to the left and then beginning again at the top of the chart or to the left of the line designated ; as the "repetition line" or limit.
The vertical line designated "repetition line" down the center of the table or chart indicates the limit of repetion of the predeter~ined system of wire strands. It will be noted that the first strand size to the left of the line is in each case the next continuing size strand in the series continued from the diagonal series directly above. The strand size immediately to the right of the line is, however, a ~ ~ , , ~ . ::, , . . :

repet~tion of the last strand size in the immediat~ly preceding dlagonal column, constructed, however, of more .188 inch wires and less .250 inch wires. In each case the actual size of the strands as compared with the nominal size is slightly greater in the strands to the right of the repetition line than to the left of the line.
Since the use of increasing numbers of smaller wires in place of larger wires requires the use of more total wires to attain the same diameter strand, it is advantageous to use more of the larger size wires since the wire is then not only subjected to fewer drawing operations, but the number of wires to be handled is also less. It will be recognized furthermore, that it is often a serlous disadvantage to use more wires than necessary in a construction since a few more wires in a construction may result in having to pass the strand through the stranding apparatus additional times. Therefore, ~he preferred strand constructions to the left of the repetition line will normally be used in the series. If, however, alternate constructions using proportionately more of the smaller wires are desired for one application or another the alternative constructions to the right of the line may also be used and are encompassed in the present invention.
This invention is useful for the production of wire strand such as bridge strand, strand for use for boom pendants and other types of structural and semi-structural strands such as the strand used for roof supports and guy lines and the like, and also working strands such as used for drag lines and the like, and even strand used in making wire rope and the like.

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~t is also adyantageous to use a .261 inch in place of the .250 inch ~ire size for the center wires of the strands and it would also be advantageous to use a somewhat larger size wire in place of the .188 inch wire in the second e~bodiment when this wire is to be used as the center wire of the strand. Such a wire size might be a .195 inch or more diameter wire. It wlll be clear also that in both instances the amount by which the actual size of the center wire of the strand exceeds its nominal size is not critical and a large number of sizes of slightly enlarged wires with respect to nominal size may be used so long as the wire is sufficiently enlarged to provide some clearance between the wires stranded about the enlarged wire, but not so large as to provide excessive clearance be~ween the outer wires.
A range of ten to fifteen thousandths of an inch increase in the center wire size is very satisfactory in most instances. Thus an oversize .250 inch wire would desirably be from .261 ~o .266 inches in diameter and an oversize .188 inch wire would desirably be from .198 to .203 inches in diameter. Because of wire geometry it is more desirable that .250 inch wire be oversize when used as the center wire than that .188 inch wire be over-: size. It will be evident also that when other actual wire sizes are used in place of the .188 inch and .250 inch wire for the outer wire layers of the strand ~he same general additional size increment for the center wire is also ;~
desirable, but, in the same manner, not critical. The use of an oversize - wire for the .188 inch center wire does, of course, involve the stocking of an extra wire size so that the method of the invention would require in actuality, if practiced with desirably oversized center wires, four stock wire slzes rather than two. however, since there is only a singl~

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relatively short length of center wire ln each strand, the inventory involved i~ not great.
The invention is not restricted, of course, to the use of .188 inch and .250 inch wires in either the outer or innner layers of the strands, but only to the stocking, basically, of two wire sizes which differ from each other in diameter by a predetermined even fraction, including one, of the predetermined desired interval between strands in the series of strands to be made and in which the smaller of the two wires is three-quarters of the size of the larger of the two wires. Any s~rand diameter confoTming to the predetermined interval between strands, or multiples of this interval, can then be built up using the two wire sizes. The measurement of the wires and strands may be in either the English system as illustrated or the metric system, so long as the basic size relationships and constructions remain the same.

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Claims (8)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR PRIVILEGE
IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A method of expeditiously providing wire strand in a predetermined range of regularly increasing strand sizes with regular intervals there-between from a wire strand production facility comprising:
(a) stocking a supply of wire in two sizes wherein the first wire is a predetermined size smaller than the second wire equal to the predeter-mined intervals between the wire strand sizes, and is three-quarters of the diameter of the second wire, (b) fabricating an order of strand from said predetermined range of stock sizes of strand by:
(1) closing the strand in a stranding machine using one of the two wire sizes for the center wire of the strand, and (2) building up the remainder of the strand from a combination of operations in wire stranding apparatus wherein each operation is comprised of one or the other of the sizes of wires to provide a strand within the pre-determined range of a series of sizes by providing a sequence of operations of wires in accordance with the following sequence of operations to attain any desired size of wire strand conforming to the predetermined series of wire strand sizes:

etc.
and wherein the center wire size alternates between said first wire and said second wire size beginning with the use of the first wire size in a strand having a diameter of unity and the unity plus four and unity plus five strand sizes of the series do not exist.

2. A method of expeditiously providing wire strand in a predetermined range of regularly increasing strand sizes with regular intervals therebetween from a wire production facility comprising:
(a) stocking a supply of wire in two sizes wherein the first wire is a predetermined size smaller than the second wire equal to the predeter-mined intervals between the wire sizes and is three quarters of the diameter of the second wire, (b) fabricating an order of strand from said predetermined range of stock sizes of strand by:
(1) closing the strand in a stranding machine using one of the two wire sizes for the center wire of the strand, (2) building up the remainder of the strand from a combination of operations in wire stranding apparatus wherein each operation is comprised of one or the other of the sizes of wires.

3. A method of expeditiously providing wire strand in a predetermined range of increasing strand sizes with regular size intervals therebetween from a wire strand production facility comprising:
(a) stocking a supply of wire in a first principal wire size and a second principal wire size wherein the first wire is a predetermined size smaller than the second wire substantially equal to the predetermined interval between wire strand sizes and is substantially three-quarters of the diameter of the second wire size, (b) fabricating an order of strand from said predetermined range of stock sizes of strand by:
(1) closing the strand in a stranding machine using one of the two wire sizes for the center wire of the strand, and (2) building up the remainder of the strand from a combination of operations wherein each operation is comprised of wires composed of one of the wire sizes in a sequence such that:
(i) the first strand size of the series is comprised of a first center wire and an operation of first wires laid thereabout, (ii) the second strand size is comprised of a second center wire and an operation of first wires laid thereabout, (iii) the third strand size is comprised of a first center wire and an operation of second wire laid thereabout, (iv) the fourth strand size is comprised of a second center wire and an operation of second wires laid thereabout, (v) the fifth and sixth strand sizes are non-existent, (vi) the seventh strand size is comprised of a first center wire and two operations of first wires laid thereabout, (vii) the eighth strand size is comprised of a second center wire and two operations of first wires laid thereabout, (viii) the ninth strand size is comprised of a first center wire and one operation of first wires and one operation of second wires laid thereabout, (ix) the tenth strand size is comprised of a second center wire and one operation of first wires and one operation of second wires laid thereabout, (x) the eleventh strand size is comprised of a first center wire and two operations of second wires laid thereabout, (xi) the twelfth strand is comprised of a second center wire and two operations of second wires laid thereabout, (xii) the thirteenth strand is comprised of a first center wire and three operations of first wires laid thereabout, (xiii) the fourteenth strand is comprised of a second center wire and three operations of first wires laid thereabout, (xiv) the fifteenth strand is comprised of a first center wire and one operation of second wires and one operation of first wires laid thereabout, and (xv) each succeeding strand in the series is made by alternating the size of the center wire between the first and second wire sizes for each successive strand in the series and each time the center wire changes to a first wire changing one of the outer operations of the strand to a second wire size provided further that each time the center wire and all the outer opera-tions of the strand become second wires the next strand size in the series will be comprised in part of a first center wire and three operations of first wires laid thereabout.

4. A method of providing wire strand according to claim 3 wherein only the strands of the predetermined series having a second size center wire are made.

5. A method of providing strand according to claim 4 wherein the first wire is substantially .188 inches in diameter and the second wire is sub-stantially .250 inches in diameter.

6. A method of providing strand according to claim 5 wherein the first strand in the predetermined series of stock strands is a one inch diameter strand and the series of strands is thereafter complete.

7. A method of providing strand according to claim 3 wherein only the strands of the predetermined series having a first size center wire are regularly made.

8. A method of providing strand according to claim 3 wherein only selected strand members of the predetermined series are regularly produced.