US3316068A - Wire belt for use in paper making machines - Google Patents

Description

April 25, 1967 A. G. HOSE ET AL WIRE BELT FOR USE IN PAPER'MAKING MACHINES Original Filed March 20, 1962 INVENTORS Flmzeo G. Hose m LRURENCE D. Kuusmm BY United States Patent Office 3,316,068 Patented Apr. 25, 1967 3,316,068 WIRE BELT FOR UtiE IN PAPER MAKiNG MACHlNES Alfred G. Hose, Cleveland, and Laurence D. Kunsman, Willoughby, Ohio, assignors to The Lindsay Wire Weaving Company, Cleveland, Ohio, a corporation of Ohio Continuation of application Ser. No. 181,208, Mar. 2t), 1962. This application Oct. 21, 1965, Ser. No. 5tl5,ll31 1 Claim. (Cl. 29-183) This application is a continuation application of US. patent application Ser. No. 181,208, filed Mar. 20, 1962, in the names of Alfred G. Hose and Laurence D. Kunsman and now abandoned.

This invention rel-ates to wire and woven wire belts which are intended for use with paper making machines or the like and the method of making the same.

In conventional practice, wire belts for use with Fourdrinier paper making machines are woven from soft annealed warp wires and shute. The warp wires are normally comprised of C Type Phosphor bronze containing about 8% tin, 0.25% phosphorus, and the balance being copper. The shute wires are usually comprised of brass containing about to zinc, with the remainder being copper. As the brass is softer and ordinarily less corrosion resistant, it is commonly utilized as a filler and helps to absorb some of the demands put on the warp wires, which must effectively withstand all of the abrasive, and most of the fatigue requirements resulting from the reverse bends of the belt caused in passing over the component parts of the paper making machine.

It has been experienced that wire belts for use in Fourdrinier paper making machines must have certain characteristics of porosity and uniformity as well as resistance to damage, fatigue failure, wear and corrosion in order to provide the optimum desired operational conditions when used on such paper making machines. Heretofore, wire belts have been found to have a relatively short life, due to these various operational requirements, although efforts have been made to increase the efficiency and usability of the belts. To a great extent, the need to replace the conventional soft annealed brass, bronze or Phosphor bronze wires has been due in part to the damage effects prevalent in many paper mill processes.

In order to overcome the difficulties presented by these damage effects, efforts have been made to develop other alloys having greater strength properties, but, significantly, always in the soft annealed state. Such alloys as the stainless steels, for instance, have been found to be of application in overcoming certain corrosion problems in the operation of Fourdrinier belts, but the increased belt strength resulting from the higher elastic modulus of stainless alloys has not been useful because it causes premature fatigue failures. For the purpose of illustration, stainless alloys have an elastic modulus of nearly twice that of Phosphor bronze warp, and therefore a wire belt woven from stainless warp would be subject to a proportionate increase in fatigue stress while operating on a paper machine. in the past, other warp alloys with different strength properties than the conventional Phosphor bronze warp have also been used in an attempt to gain strength to resist the effects of damage, but have not been significantly advantageous.

In the past, the warp, whether of a conventional or nonconventional alloy, was invariably woven in the soft annealed state, because it was generally accepted that a certain amount of tensile elongation was necessary for the Warp to withstand the crimping in weaving without cracking. A tensile elongation of in 5 inches was generally believed to be the acceptable minimum for warp.

Because of this requirement, most efforts at evaluating warp alloys were directed to the use of the alloys in the soft annealed state. Consequently, any improvement in the damage resistance of the resulting wire cloth was limited to that gained only by the physical manifestations resulting from changes in chemical composition or alloying content;

We have found, however, that we can provide warp and shute wires susceptible for weaving into wire belts for use with Fourdrinier paper making machines which have improved resistance to damage, fatigue failure and wear, wherefore it is possible to utilize su-ch wire belts over a longer period of life. To achieve these results, the properties of the wire belt have been found to be improved by weaving it from warp and shute wire alloys which have been subjected to predetermined mechanical Workhardening operations. The improvement in properties is determined by the degree of work-hardening, which can be accomplished by wire drawing or wire stretching techniques.

Accordingly, a primary object of the present invention is to provide a wire as well as the method of making such wire adapted for use in paper making machines, having improved resistance to damage, fatigue failure, and wear. Corrosion may also be improved by applying the method of making the wire to more corrosion resistant alloys such as the stainless steel alloys.

Another object of the present invention is to provide a wire made primarily from a copper base alloy as well as the method of making such wire adapted for use in paper making machines, and having improved resistance to damage, fatigue failure, wear and corrosion.

A further object of the present invention is to provide a wire made primarily from a stainless steel alloy as well as the method of making such wire, and adapted for use in paper making machines having improved resistance to damage, fatigue failure, wear and corrosion.

A still further object of the present invention is to provide a wire belt adapted for use in paper making ma chines and having an improved resistance to damage, fatigue failure, wear and corrosion.

Another object of the present invention is to provide a wire belt adapted for use in paper making machines made primarily from a copper base alloy having improved resistance to damage, fatigue failure, wear and corrosion.

A further object of the present invention is to provide a wire belt made primarily from a stainless steel alloy adapted for use in paper making machines having improved resistance to damage, fatigue failure, wear and corrosion.

Other and further objects of the present invention will be apparent from the following description and claims, and are illustrated in the accompanying drawing, which, by way of illustration, shows a preferred embodiment of the present invention, and the principles thereof, and what is now considered to be the best mode in which to apply such principles. Other embodiments of the invention embodying the same or equivalent principles may be applied by those skilled in the art, and structural changes may be made, as desired, without departing from the scope of the present invention.

In the drawings:

FIG. 1 is a plan view of a woven wire belt of the present invention showing a twill weave having its ends joined by a conventional seam;

FIG. 2 is a sectional view taken on a plane indicated by the lines 22 of FIG. 1;

FIG. 3 is a diagrammatic view of the wire cloth of the present invention formed into an endless belt mounted on the rollers and intermediately passing across a suction box of a Fourdrinier paper making machine.

For purposes of illustration, we have shown our invention as a woven wire cloth, shown generally at 2, having a twill weave, wherein the warp wires are designated 8 and the shute wires 10. One end of the cloth is attached to the other end by means of a seam 12 which may be made, for example, by directly brazing the ends of each warp wire to the opposite ends of the same warp wire to form an endless belt 14, as shown at FIG. 3.

It will be recognized that different weaves may be employed, as is known in the art. As shown herein, the wire cloth 2 from which the wire belt 14 is fabricated, is woven in an over-one, under-two twill pattern, such that the warp wires 8 on the inner surface of the belt provide long knuckles 16 for engagement with the suction boxes.

As illustrated in one embodiment of our invention, we have found that the warp and shute wires will effectively incorporate improved properties of resistance to damage, fatigue failure, wear and corrosion, and yet retain the desired characteristics of ductility by subjecting the alloy composition of the wire to predetermined work-hardening operations.

In one form of this embodiment, a Fourdrinier Grade Bronze warp wire for use in a 55 mesh belt may be reduced from a standard rod size which has been drawn to an intermediate size Wire of about 0.050 inch.

When a purchaser of wire for use in the production of paper making wire belts specifies a particular size or diameter of wire for use in redrawing prior to weaving paper making wire cloth, such wire is produced by reducing standard rod size to wire of the ordered size. Such ordered size of wire conventionally receives a complete anneal resulting in wire that is in the dead soft condition. In other words, it is understood by those skilled in the wire drawing art that the wire ordered by a wire weaver for redrawing is to be drawn down from a standard rod size to the specified size, with a complete anneal, unless otherwise specified on the order for the wire.

The 0.050 wire may then be cold drawn to about 0.0125 inch and annealed at a temperature between 800 F. to 1000 F. and at speeds sufiicient to secure a Wire yield strength /2% off-set) in a range from about 30,000 to 40,000 p.s.i. This initial draw corresponds to a reduction in cross-sectional area of about 94%. The wire is then cold drawn to the finished size of about 0.0105 inch. This final draw corresponds to a reduction in cross-sectional area of about 30%. In this form, the yield strength would be about 105,000 p.s.i., with an elongation of about 2% in five inches. The composition of such Fourdrinier Grade Bronze may be by weight as follows:

Percent Tin 7.2 to 8.0 Phosphorous 0.25 to 0.35 Iron, if present, max. 0.05 Copper Balance In another form of this embodiment, the shute wire used in a 55 mesh belt may be a Fourdrinier Grade Brass reduced from a standard rod size and drawn to an intermediate size of about 0.128 inch. The wire may then be cold drawn to about 0.0125 inch and annealed at a temperature between about 900 F. to 1100" F. and at speeds suflicient to secure a wire yield strength /2% off-set) in a range from about 20,000 to 30,000 p.s.i. This initial draw corresponds to a reduction in cross-sectional area of about 99%. The wire may then be cold drawn to a finished size of about 0.012 inch for weaving. This final draw corresponds to a reduction in cross-sectional of about 8%. In this form, the wire yield strength would be about 45,000 p.s.i. with an elongation of about 6% in five inches. The composition of such Fourdrinier Grade Brass may be by weight as follows:

In another form of this embodiment, the warp wire in a 55 mesh belt may be of a Grade 316L or 18-9 LW Grade Stainless Steel, which has been reduced to an intermediate wire size of about 0.028 inch. The warp wire may then be cold drawn to about 0.0113 inch and annealed at a temperature of between 1800 F. to 1900" F. to secure a wire yield strength /2% off-set) between about 55,000 to 65,000 p.s.i. This initial draw corresponds to a reduction in cross-sectional area of about 85%. The warp wire may then be cold drawn to a finished size of about 0.0105 inch for weaving. This final draw corresponds to a reduction in cross-sectional area of about 12%. In this form the yield strength would be about 125,000 p.s.i. with an elongation of about 2% in five inches. The composition of the 316L and the 18-9 LW Grade Stainless Steel, by weight, may be, respectively, as follows:

Grade 316L Stainless Steel: Percent Chromium 16.0 to 18.0 Nickel 10.0 to 14.0 Carbon, max. Trace to 0.03 Molybdenum 2.00 to 3.00 Manganese, max. Trace to 2.00 Silicon, max. Trace to 1.00 Phosphorous, if present, max. 0.045 Iron Balance 189 LW Grade Stainless Steel: Percent Chromium 16.0 to 18.0 Nickel 10.0 to 14.0 Carbon, max. Trace to 0.03 Copper 2.0 to 4.0 Silicon, max. Trace to 1.00 Manganese, max. Trace to 2.00 Phosphorous, if present, max. 0.045 Iron Balance In another form of this embodiment, the shute wire in a 55 mesh belt may be of a Type 304 Stainless Steel which has been reduced to an intermediate size wire of about 0.028 inch. The shute wire may then be cold drawn to about 0.0125 inch and annealed at a temperature of between about 1800 F. to 1900 F. to secure a wire yield strength /2% cit-set) in the range of about 45,000 to 55,000 p.s.i. This initial draw corresponds to a reduction in cross'sectional area of about The wire is then cold drawn to a finished size of about 0.012 inch for weaving. This final draw corresponds to a reduction in crosssectional area of about 8%. In this form, the yield strength would be about 85,000 p.s.i. with an elongation of about 2% in five inches. The composition of such type 304 Stainless Steel, by weight, may be as follows:

Percent Chromium 18.0 to 20.0 Nickel 8.0 to 12.0 Carbon, max. Trace to 0.08 Manganese, max. Trace to 2.00 Silicon, max Trace to 1.00 Phosphorous, if present, max 0.045 Sulphur, if present, max. 0.030 Iron Balance In this embodiment, though we have illustrated the warp and shute wires embodying the invention as comprised of a Pourdrinier Brass, Fourdrinier Bronze and specific stainless steel alloy compositions, it is to be understood that other copper base and stainless steel alloys may be successfully utilized to achieve similar beneficial results. For example, we have discovered that with a work-hardening in accordance with the principles of the present invention, commercial grades of copper and brass may be made sufficiently strong to make a damage resistant belt. In most cases, after the work-hardening, the reserve ductility of the wire is ample for weaving and bending operations, while the yield strength has increased significantly over conventional soft annealed wire of conventional compositions.

Moreover, when reference is made to stainless steel, we mean austenitic stainless steel of the A151 300 Series, containing basically 18% chromium, 8 to 12% nickel, carbon below .03% with sufficient corrosion resistant alloy additions. With respect to the latter, we have found that small amounts such as 2% to 3% of molybdenum will increase the sulfide corrosion resistance of the wire without affecting the work hardening rate of the wire.

The particular temperatures most suitable for annealing and the degree of work-hardening varies, depending upon such factors as the particular composition and size of the wire, as well as the size of the body being reduced or annealed. For example, with a coarse open wire mesh, when larger size warp or shute wire is used, the degree of hardening would be more than if a smaller size of warp or shute wire is used, as in a tight fine mesh.

In the present invention, though we have illustrated work-hardening the Warp and shute Wire by drawing through dies of predetermined size, it is to be understood that the alloy compositions of the wire may be equally amenable to other work-hardening techniques. For example, cold reduction of copper base or stainless steel alloy compositions are similarly amenable to Wire-stretching techniques.

A Wire belt embodying the present invention, not only possesses the novel characteristics of resistance to damage, but also resistance to wear, fatigue, and corrosion. The resistance to fatigue becomes exceedingly important in present operations, wherein paper making machine speeds in many cases exceeds over 2000 feet per minute. Consequently, as machine speeds increase the wire must have sumcient bend resistance if it is not to fail from fatiguecracking long before it i worn out.

In accordance with the foregoing description, it will be apparent that the present invention provides a woven wire belt having improved characteristics which allow the belt to be readily adapted for use in any paper making mill. Furthermore, the increased life of the wire belt of the present invention provides a substantial economic saving, not only from a material standpoint with respect to the belts themselves, but also from an operational standpoint, due to the minimization of machine-downtime caused by frequent replacement of damaged belts.

Thus, while we have illustrated herein a preferred embodiment of our invention, it is to be understood that changes and variations may be made by those skilled in the art without departing from the spirit and scope of the appended claim.

We claim:

A Wire belt made of interwoven set of hard-drawn warp and shute wires for use with Fourdrinier type paper making machines, the warp wires essentially consisting of about 7.2% to 8.0% tin, about 0.25% to 0.35% phosphorous, iron less than about 0.05% maximum, with the balance being substantially all copper, and having a yield strength, as finished, in excess of 100,000 p.s.i. with an elongation in five inches of about 2%, resulting from cold reduction of the cross-sectional area of the wire in excess of 90%, heating the wire at a temperature between about 800 F. to 1000 F., and further cold reduction of the cross-sectional area of the wire of about 30%; the shute wires essentially consisting of about 14.0% to 16.0% zinc, lead less than about 0.05% maximum, iron and nickel less than about 0.05% maximum, phosphorous less than about 0.005% maximum, with the balance being substantially all copper, and a yield strength, as finished, of about 45,000 p.s.i. with an elongation in five inches of about 6% resulting from cold reduction of the crosssectional area of the wire in excess of 90%, heating the wire at a temperature between about 900 F. to 1100 F., and further cold reduction of the cross-sectional area of the wire of about 8%.

References Cited by the Examiner UNITED STATES PATENTS 1,934,643 11/1933 Rafton 29-1835 2,496,052 l/1950 Hose et al. 74-239 2,718,791 9/1955 Hose et a1. 74-239 3,046,166 7/1962 Hartmann 148-115 3,067,072 12/1962 Leffingwell et a1. 148-12 3,076,361 2/1963 Epstein et a1. 148-12 3,100,729 8/1963 Goller 148-123 3,138,493 6/1964 Smith 148-115 3,177,113 4/1965 Golden et al. -239 3,220,806 11/1965 Ruschmann 29-183 3,222,143 12/1965 Macchini 29-183 OTHER REFERENCES Metals Handbook, vol. 1, 8th ed., 1961, pages 153160 and 1027-1032.

DAVID L. RECK, Primary Examiner.

N. F. MARKVA, Assistant Examiner.

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