US3240635A - Wire cloth and wire belts for use in paper making machines and method of making such wire cloth and wire belts - Google Patents

Description

March 15, 1966 A. G. HOSE ET AL 3,240,635

WIRE CLOTH AND WIRE BELTS FOR USE IN PAPER MAKING MACHINES AND METHOD OF MAKING SUCH WIRE CLOTH AND WIRE BELTS Filed May 17, 1962 Fig. 2

INVENTORS Pump 6. Hose rmo BY Lnuazucs D. KUNSMHH H OIZNEYS United States Patent C "ice 3,240,635 WIRE CLOTH AND WIRE BELTS FOR USE IN PA- PER MAKING MACHINES AND METHOD OF MAKING SUCH WIRE CLOTH AND WIRE BELTS Alfred G. Hose, Cleveland, and Laurence D. Kunsman, Willoughby, Ohio, assignors to The Lindsay Wire Weaving Company, Cleveland, Ohio, a corporation of Ohio Filed May 17, 1962, Ser. No. 195,572 Claims. (Cl. 148-123) This invention relates to wire cloth 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 softannealed warp and shute wires. The warp wires are normally comprised of Type C Phosphor bronze containing about 8% tin, 0.25% phosphorus, and the balance being copper. The shute wires are usually comprised of brass containing 15% to zinc, with the remainder being copper. The brass is utilized as a filler, and as such helps to absorb some of the demands put on the warp wires in the belt. The warp wire must effectively withstand all of the tensile, fatigue, and wear demands put on the belt during its operation.

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, Fourdrinier belts have been found to be prone to damage during operation, and such damage limits the useful wear life of a wire belt. Many efforts have been made to weave wire belts characterized by having a greater resistance to damage, but the attainment of such properties have been limited by the soft-condition of the warp and shute wires, from which it has been found necessary to Weave Fourdrinier wire belts.

In the past, the composition of the warp and shute wire alloys have been varied to gain increases in such properties as elastic modulus, whereas various weaving configurations have been attempted, and a variety of changes have been made in warp and shute wire sizes in attempts to improve resistance to damage. For example, stainless wire alloys, which have an elastic modulus of nearly twice that of the conventionally used Phosphor bronze and brass have been woven into belts but have failed to show superior resistance to damage. Similarly, other high modulus alloys, such as nickel and Monel, have also been used, but have been found to equally be unsatisfactory. Consequently, attempts to improve resistance to damage have been limited to only those gained by changes in alloy composition and not in the treatment to the alloy, other than changes in soft annealing practices and changes in the manner of Weaving.

While it is understood that the weaving process causes basic alterations to the internal structure of the warp wire at the knuckles (crimps), that part of the warp not involved in the crimp radius, receives no alteration. This part consists of the entire bottom knuckle and the sloped approach to the top knuckle. The alterations mentioned cause some strain-hardening to take place, but at the expense of loss in cross-section. Thus, the hardening effect due to weaving is not uniform and becomes diminished, in a characterized manner, by the stretching which takes place in forming the crimps or knuckles.

Additionally, the shute wire, which, While essentially a filler wire, is nevertheless, a component from which the wire cloth must derive part of its strength and resistance to damage. It is weakened by the weaving action, which Patented Mar. 15, 1966 partially shears its diameter and distorts it into a configuration not unlike a notched, twisted column. The shute wire cannot, therefore, be expected to add significantly to Lhe total strength and damage resistance of a conventional elt.

We have found, however, that by weaving wire cloth from heat-treatable wire alloys in the annealed state, finishing the cloth so woven into a belt, and then subjecting the belt to a heat treatment, that the belt has a substantially improved resistance to damage. Additionally, We have found that other properties, such at fatigue, wear and corrosion resistance, may also be improved, depending upon the degree of heat treatment and choice of warp and shute alloy composition amenable to such heat treatment.

Accordingly, a primary object of the present invention is to provide a wire cloth as Well as a method of making such cloth, and adapted for use with paper making machines having improved resistance to damage, fatigue failure, wear and corrosion.

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

A still further object of the present invention is to pro vide a wire belt, as well as the method of making such belt, and adapted for use with paper-making machines 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 precipitation hardenable alloys as well as the method of making such belt, adapted for use in paper-making machines having improved resistance to damage, fatigue failure, wear and corrosion.

An additional object of the present invention is to provide a method of treating wire cloth, endless belts or the like, made primarily from precipitation hardenable alloy compositions, and adapted for use with 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 drawings, which, by way of illustration, show 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 these 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 perspective View of the wire cloth of the present invention formed into an endless belt by means of a conventional seam adapted for use with paper making machines;

FIG. 2 is a diagrammatic view of the wire cloth of the present invention mounted on rollers and intermediately passing through a heat treating furnace.

For purposes of illustration, the preparation of the warp and shute wire, from which such an improved belt may be made, may normally be carried out by drawing the wire down to a finished size from an intermediate wire size, and subjecting the wire to a solution heat treatment. Generally speaking, the solution heat-treatment may vary with the condition and character of the alloy composition and may normally be carried out at a temperature and rate sufficient to secure the desired ductility and yield strength suitable for weaving into a wire cloth.

In the woven condition, the wire cloth is preferably subjected to controlled age-hardening operations. In such case, the wire cloth may first be seamed by suitable brazing operations into an endless belt, as noted generally at 1 of FIG. 1. Having installed the scam, the endless belt may then be moved to a stretcher 2 (FIG. 2) where stretcher rolls 3 and 4 are adapted to stretch the belt to the desired paper machine length. In some cases, where slight irregularities appear on the surface of the belt, it may be desirable to smooth the belt down in those areas in the customary manner, and such smoothing operations may be also applied after heat treatment, if necessary. To commence the age-hardening heat treatment, the belt may be moved slowly over the stretcher rolls (3 and 4) through a suitable heat-treating furnace, such as shown generally at 5, and heated at a temperature and at a rate sufficient to cause the desired amount of hardening of the warp and shute wires. The belt may then be cooled to room temperature. This heating cause-s internal structural changes in the warp and shute wire resulting in a hardening of the wire, which is manifest in an increase in tensile strength, fatigue life, wearability, and damage resistance of the belt.

As the precipitation-hardening of the alloy composition comprising the wire depends upon temperature, as well as upon time, there may be several treatments which produce the desired characteristics of a belt suitable for use with paper making machines. Additionally, optimum age-hardening characteristics depend upon the composition of the alloy and to some extent upon its structural condition; that is, upon the amount of prior mechanical working of the metal.

Accordingly, in one form of this embodiment, the warp and shute wires which may be comprised of a Berylco 25 alloy, may be cold drawn from an intermediate size down to a finished wire size of from 0.0031 inch to 0.013 inch and solution heat-treated to secure the desired yield and tensile strength suitable for weaving. In this form, the yield strength of the Berylco 25 warp would be about 45,000 p.s.i. at a tensile strength of about 67,000 pounds per inch of width with an elongation of about 50% in 5 inches. The Berylco 25 shute would have a yield strength of about 35,000 p.s.i. and a tensile strength of about 47,000 pounds per inch of width with an elongation of about 36% in 5 inches.

The warp and shute wires may then be woven into a 56-36 mesh wire cloth in the normal manner. As woven, the warpwise tensile strength of the cloth was found to be about 248 pounds per inch (in width) with a warpwise bending fatigue resistance of about 12,000 (cycles to failure). In the as-woven condition, the wire cloth may then be subjected to an age-hardening by heating to a temperature of from 475-650 F. and holding at such temperature for a period of A to 3 hours to cause the necessary increase in the desired amount of tensile strength. The wire cloth may then be air cooled to room temperature. After such heat treating, the warpwise tensile strength was found to be about 300 pounds per inch with a warpwise bending fatigue resistance of about 16,000 (cycles to failure).

Additional increases in fatigue life as well as improved uniformity of property gains may be achieved by an alternative intermediate solution-annealing treatment carried out between the weaving and age-hardening operations. In this form, after weaving the wire, into cloth, the cloth may be rolled onto a heat-resistance pole, heated to about 1475 F. and held at such temperature for about minutes. The wire cloth may then be water quenched as rapidly as possible to retain the solid solution of beryllium in copper. Another method by which this treatment may be effected is by the heating of the wire cloth to about 1475 F. as it is unrolled through the furnace, and subjecting the wire cloth to a water quenching operation as it emerges continuously from the furnace. Rerolling of the wire cloth may then be accomplished for the purpose of seaming and finishing the wire cloth into a belt, after which the age-hardening treatment may be undertaken to cause the desired improvement in properties. It is to be understood, however, that such additional solutionannealing treatment may be applied to the belt, as woven, in passing through a suitable heat treating furnace (FIG. 2) to cause the desired improvement in properties.

For the purpose of disclosure, the nature of the intermediate solution-annealing treatment, which is stabilized by the water quenching operation is such that the effects of heterogenous straining of the structure during weaving is eliminated. This allows a uniform age-hardening to occur, thus increasing the fatigue life of the wire belt to a level beyond 16,000 cycles to failure. In this embodiment, the composition of such Berylco 25 alloy may be as follows:

Percent Beryllium 1.80-2.25 Cobalt 0.18-0.30

Copper Balance Similarly, in another form of this embodiment, the warp and shute wires, which may be comprised of Elgiloy alloy, may be cold reduced from an intermediate size down to a finished wire size of about 0.0031 inch to 0.013 inch. Hereagain, the wire may be subjected to a solution heat-treatment to secure the desired yield and tensile strength suitable for weaving. The warp and shute wires may then be woven into a 56-36 mesh wire cloth in the normal manner. The yield strength of the Elgiloy warp would be about 60,000 p.s.i. at a tensile strength about 110,000 pounds per inch of width with an elongation of about 50% in 5 inches. The Elgiloy shute would have a yield strength of about 50,000 p.s.i. at a tensile strength of about 95,000 pounds per inch of width with an elongation of about 60% in 5 inches.

The warp and shute wires may then be woven into a 56-36 mesh wire cloth in the normal manner. As woven, the warpwise tensile strength of the cloth is about 250 pounds per inch (in width) with a warpwise bending fatigue resistance of about 9,600 (cycles to failure). Having performed the desired seaming and stretching operations, the wire belt may then be subjected to a heating or age-hardening at a temperature of 600-1000 F. and held for a period of about 3-5 hours to effect the desired increase in properties. The wire belt may then be aircooled to room temperature. In the finished and heattreated condition, the warpwise tensile strength of the wire belt is about 500 pounds per inch (in width) with a warpwise bending fatigue resistance of about 31,000 (cycles to failure). The composition of such Elgiloy alloy may be as follows:

Percent Cobalt 40 Chromium 20 Nickel 15 Molybdenum 7 Manganese 2 Carbon 0.15 Beryllium 0.04 Iron Balance For purposes of disclosure, when reference is made to the alloy composition of the warp and shute wires, we refer to those alloys which are age-hardenable. In this respect, and by way of specific example we have found the alloy composition of Berylco 25 and Elgiloy to yield highly satisfactory results. It is to be understood, however, that other age-hardenable alloy compositions will produce similar beneficial results. For example, we have found that 17-7 PH stainless steel, comprising 16.0 to 18.0% chromium, 6.5 to 7.5% nickel, 0.9% carbon, 0.75 to 1.50% aluminum with the balance being iron, will provide equally beneficial results in producing a woven wire belt suitable for use with paper making machines. In this connection, it is to be understood that the warp and shute wires may be of the same alloy composition in each case, or the warp and shute wires may be of respectively different but compatible alloy compositions in each case, modified only slightly in yield and tensile strength to weave properly.

In accordance with the foregoing description, it will be apparent that the wire belt of the present invention not only possesses the novel characteristics of resistance to damage, but also resistance to wear, fatigue and corrosion. Resistance to fatigue becomes exceedingly important in present paper making operations, wherein paper making machine speeds in many cases exceeds over 2000 feet per minute. Consequently, as machine speeds increase the wire belt must have sufficient bend resistance if it is not to fail from fatigue-cracking long before it is actually worn out. Furthermore, 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 form from an operational standpoint, due to the relatively low replacement cost of such improved 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 claims.

We claim:

1. In the process for making Fourdrinier wire cloth having interwoven sets of Warp and shute wires made from precipitation hardenable metal alloys selected from the group consisting of copper-beryllium-cobalt alloys, iron-nickel-chromium-cobalt alloys, and iron-chromium alloys, the improvement comprising the steps of subjecting the wire as woven to a precipitation hardening, said precipitation hardening comprising heating the wires to a temperature of between about 475 F. to 1000 F. for a period of time ranging between about one-fourth to five hours, and then cooling the wires to room temperature to provide in the hardened cloth a warpwise tensile strength of between about 300 lbs. to 500 lbs. per inch of width, and a warpwise bending fatigue resistance of between about 16,000 to 31,000 cycles to failure.

2. In the process for making Fourdrinier wire cloth having interwoven sets of warp and shute wires made from precipitation hardenable metal alloys selected from the group consisting of copper-beryllium-cobalt alloys, iron-nickel-chromium-cobalt alloys, and iron-chromium alloys, the improvement comprising the steps of subjecting the wires to a solution-heat treatment and quenching the wires to an unhardened condition, forming the unhardened wires into the desired woven construction, subjecting the wires as woven to a precipitation hardening by heating the wires to a temperature of between about 475 to 1000 F. for a period of time ranging between about one-fourth to five hours, and then cooling the wires at a temperature and rate sufficient to provide in the woven and hardened condition of the cloth a warpwise tensile strength of between about 300 lbs. to 500 lbs. per inch of width and a warpwise bending fatigue resistance of between about 16,000 cycles to 31,000 cycles to failure.

3. In the process for making Fourdrinier wire cloth having interwoven sets of warp and shute wires made from precipitation hardenable copper-beryllium-cobalt alloys, the improvement comprising the steps of subjecting the wire as woven to a precipitation hardening, said precipitation hardening comprising heating the wires to a temperature between about 475 F. to 650 F. for a period of time ranging between about A to 3 hours, and then cooling the wires to room temperature to provide in the hardened cloth a warpwise tensile strength of about 300 lbs. per inch of width and a warpwise bending fatigue resistance of about 16,000 cycles to failure.

4. A process in accordance with claim 3, wherein the warp and :shute wires are subjected to a solution heat 'treatment prior to said precipitation hardening, said solution heat treatment comprising heating the wire to a temperature of about 1,475 E, for a period of time of about 15 minutes, and then quenching the wire.

5. A process in accordance with claim 3, wherein the precipitation hardenable alloy has a composition comprising, by weight, beryllium from 1.80% to 2.25%, cobalt from 0.18% to 0.30%, and substantially all of the balance being copper.

6. In the process for making Fourdrinier wire cloth having interwoven sets of warp and shute wires made from precipitation hardenable iron-nickel-chromiumcobalt alloys, the improvement comprising the steps of subjecting the wire as woven to a precipitation hardening, said precipitation hardening comprising heating the wires to a temperature of between about 600 F. to 1,000 F. for a period of time ranging between about 3 to 5 hours, and then cooling the wires to room temperature to provide in the hardened cloth a warpwise tensile strength of about 500 pounds per inch of width with a warpwise bending fatigue resistance of about 31,000 cycles to failure.

7. A process in accordance with claim 6, wherein the warp and shute wires are subjected to a solution heat treatment prior to said precipitation hardening, said solution heat treatment comprising heating the wire to a temperature of about 1,475 F. and for a period of time of about 15 minutes and then quenching the wire.

8. A process in accordance with claim 6, wherein the precipitation hardenable alloy has a composition comprising, by weight, about 40% cobalt, 20% chromium, 15% nickel, 7% molybdenum, carbon from trace to about 0.15%, beryllium from trace to about 0.04%, and substantially all of the balance being iron.

9. A process for making an endless belt for use with paper making machines, having interwoven sets of warp and shute wires made from precipitation hardenable copperberyllium-cobalt alloys, the steps including reducing the warp and shute wires from an intermediate wire size down to a finished wire size, heating the warp and shute wires to a temperature of about 1,475 F., for a period of time of about 15 minutes and quenching the wires to secure a predetermined yield and tensile strength suitable for forming into wire cloth, weaving the warp and shute wires into a woven wire cloth, joining the ends of the woven wire cloth together to form an endless belt, heating the endless belt to a temperature of about between 475 F. to 650 F. for a period of time ranging between M: and 3 hours and cooling the belt to room temperature to provide in the hardened belt a warpwise tensile strength of about 300 lbs. per inch of width with a warpwise bending fatigue resistance of about 16,000 cycles to failure.

10. A process for making an endless belt for use with paper making machines having interwoven sets of warp and shute wires made from precipitation hardenable ironnickel-chromium-cobalt alloys, the steps including reducing the warp and shute wires from an intermediate wire size down to a finished wire size, heating the warp and shute wires to a temperature of about 1,475 F. for a period of time of about 15 minutes and quenching the wires to secure a predetermined yield and tensile strength suitable for forming into wire cloth, weaving the warp and shute wires into a woven wire cloth, joining the ends of the woven wire cloth together to form an endless belt, heating the endless belt to a temperature between about 600 F. to 1,000 F. for a period of time ranging between about 3 to 5 hours, and then cooling the wire to room temperature to provide in the hardened belt a warpwise tensile strength of about 500 lbs. per inch of width with a warpwise bending fatigue resistance of about 31,000 cycles to failure.

11. A wire belt for use with paper making machines, having interwoven sets of warp and shute wires made from a precipitation hardenable copper-beryllium-cobalt alloy, heated as woven to a temperature between about 475 F. to 650 F. for a period of time ranging between about A to 3 hours, and cooled to room temperature to provide in the belt a warpwise tensile strength of about 300 pounds per inch of width and a warpwise bending fatigue resistance of about 16,000 cycles to failure.

12. A wire belt in accordance with claim 11, wherein the precipitation of hardenable alloy has a composition comprising, by weight, beryllium from 1.80% to 2.25%, cobalt from 0.18% to 0.30%, and substantially all of the balance being copper.

13. A Wire belt for use in paper making machines having interwoven sets of warp and shute wires made from a precipitation hardenable iron-nickel-chromium-cobalt all-y, heated as woven to a temperature between about 600 F. to 1,000 P. for a period of time ranging between 3 to 5 hours, and cooled to room temperature to provide in the hardened belt a warpwise tensile strength of about 500 pounds per inch of width and a warpwise bending fatigue resistance of about 31,000 cycles to failure.

14. A wire belt in accordance with claim 13, wherein a precipitation hardenable alloy has a composition comprising, by weight, about 40% cobalt, 20% chromium, 15% nickel, 7% molybdenum, carbon from trace to about 0.15%, beryllium from trace to about 0.04% and substantially all of the balance being iron.

15. A wire belt for use in paper making machines having interwoven sets of warp and shute wires made from precipitation hardenable alloys selected from the group consisting of copper-beryllium-cobalt alloys, iron- 5 nickel-chromium-cobalt alloys, and iron-chromium alloys, heated as woven to a temperature between about 475 F. to 1000 F. for a period of time ranging between about one-fourth to five hours and cooled to room temperature, to provide in the hardened belt a warpwise tensile strength 10 of between about 300 lbs. to 500 lbs. per inch of width and a warpwise bending fatigue resistance of between about 16,000 to 31,000 cycles to failure.

References Cited by the Examiner UNITED STATES PATENTS 1,975,114 10/1934 Masing et al. 148-l60 2,088,449 7/1937 Specht 2458 2,288,512 6/1937 Buchanan 2458 2,422,477 6/1947 Driver 14816O 2,482,098 9/1949 Clarke 148135 2,859,149 11/1958 Straumann 148-123 2,908,065 10/1959 Hinz 245-10 2,958,618 11/1960 Allen 148-135 DAVID L. RECK, Primary Examiner.

HYLAND BIZOT, Examiner.

Claims (2)

1. 9. A PROCESS FOR MAKING AN ENDLESS BELT FOR USE WITH PAPER MAKING MACHINES, HAVING INTERWOVEN SETS OF WARP AND SHUTE WIRES MADE FFOM PRECIPITATION HARDENABLE COPPER-BERYLLIUM-COBALT ALLOYS, THE STEPS INCLUDING REDUCING THE WARP AND SHUTE WIRES FROM AN INTERMEDIATE WIRE SIZE DOWN TO A FINISHED WIRE SIZE, HEATING THE WARP AND SHUTE WIRES TO A TEMPERATURE OF ABOUT 1,475*F., FOR A PERIOD OF TIME OF ABOUT 15 MINUTES AND QUENCHING THE WIRES TO SECURE A PREDETERMINED YIELD AND TENSILE STRENGTH SUITABLE FOR FORMING INTO WIRE CLOTH, WEAVING THE WARP AND SHUTE WIRES INTO A WOVEN WIRE CLOTH, JOINING THE ENDS OF THE WOVEN WIRE CLOTH TOGETHER TO FORM AN ENDLESS BELT, HEATING THE ENDLESS BELT TO A TEMPERATURE OF ABOUT BETWEEN 475*F. TO 650*F. FOR A PERIOD OF TIME RANGING BETWEEN 1/4 AND 3 HOURS AND COOLING THE BELT TO ROOM TEMPERATURE TO PROVIDE IN THE HARDENED BELT A WARPWISE TENSILE STRENGTH OF ABOUT 300 LBS. PER INCH OF WIDTH WITH A WARPWISE BENDING FATIGUE RESISTENCE OF ABOUT 16,000 CYCLES TO FAILURE.
2. 10. A PROCESS FOR MAKING AN ENDLESS BELT FOR USE WITH PAPER MAKING MACHINES HAVING INTERWOVEN SETS OF WARP AND SHUTE WIRES MADE FROM PRECIPITATION HARDENABLE IRONNICKEL-CHROMIUM-COBALT ALLOYS, THE STEPS INCLUDING REDUCING THE WARP AND SHUTE WIRES FROM AN INTERMEDIATE WIRE SIZE DOWN TO A FINISHED WIRE SIZE, HEATING THE WARP AND SHUTE WIRES TO A TEMPERATURE OF ABOUT 1,475*F. FOR A PERIOD OF TIME OF ABOUT 15 MINUTES AND QUENCHING THE WIRES TO SECURE A PREDETERMINED YIELD AND TENSILE STRENGTH SUITABLE FOR FORMING INTO WIRE CLOTH, WEAVING THE WARP AND SHUTE WIRES INTO A WOVEN WIRE CLOTH, JOINING THE ENDS OF THE WOVEN WIRE CLOTH TOGETHER TO FORM AN ENDLESS BELT, HEATING THE ENDLESS BELT TO A TEMPERATURE BETWEEN ABOUT 600*F. TO 1,000*F. FOR A PERIOD OF TIME RANGING BETWEEN ABOUT 3 TO 5 HOURS, AND THEN COOLING THE WIRE TO ROOM TEMPERATURE TO PROVIDE IN THE HARDENED BELT A WARPWISE TENSILE STRENGTH OF ABOUT 500 LBS. PER INCH OF WIDTH WITH A WARPWISE BENDING FATIGUE RESISTANCE OF ABOUT 31,000 CYCLES OF FAILURE.

Images