US3726757A - Composite multiple and incrementally controlled steam chamber for applying dried steam to a pulp mat - Google Patents

Abstract

A composite steam chamber extending transversely above a pulp mat for discharging steam down onto the mat; the composite chamber formed of separate individual chambers secured together including one or more central or inner chambers and an end chamber at each end of the composite structure; means for separately delivering steam into each individual chamber; each individual chamber having a bottom wall formed into ridges and valleys extending from one end wall of the chamber to the other, with steam jet orifices in the ridges; and means for drawing off moisture collecting in the valleys of each individual chamber.

Description

April 10, 1973 J. H. DUPASQUIER COMPOSITE MULTIPLE AND INCREMENTALLY CONTROLLED STEAM CHAMBER FOR APPLYING DRIED STEAM TO A PULP MAT Filed June 28, 1971 2 Sheets-Sheet 1 FIG.

R Em T QN E MV m D H H P E S O J ATTY.

Apnl 10, 1973 .1. H. DUPASQUIER 3,726,757

COMPOSITE MULTIPLE AND INCREMENTALLY CONTROLLED STEAM CHAMBER FOR APPLYING DRIED STEAM TO A PULP MAT Filed June 28, 1971 2 Sheets-Sheet 2 b I? FIG. 4

l6 3 ;Z l II 53 I JOSEPH H. DUPASQUIER 1; INVENTOR.

United States PatentO COMPOSITE MULTIPLE AND INCREMENTALLY CONTROLLED STEAM CHAMBER FOR APPLY- ING DRIED STEAM TO A PULP MAT Joseph H. Dupasquier, 5855 NW. Skyline Drive, West Linn, Oreg. 97068 Filed June 28, 1971, Ser. No. 157,175 Int. Cl. D21f /18 US. Cl. 162-290 1 Claim ABSTRACT OF THE DISCLOSURE A composite steam chamber extending transversely above a pulp mat for discharging steam down onto the mat; the composite chamber formed of separate individual chambers secured together including one or more central or inner chambers and an end chamber at each end of the composite structure; means for separately delivering steam into each individual chamber; each individual chamber having a bottom wall formed into ridges and valleys extending from one end wall of the chamber to the other, with steam jet orifices in the ridges; and means for drawing off moisture collecting in the valleys of each individual chamber.

BACKGROUND OF THE INVENTION US. 'Pat. No. 2,838,982, issued June 17, 1958, describes an apparatus for applying dried steam down onto a traveling pulp mat in order to aid in the evaporating of water from the pulp mat. The device of the present invention is very similar to that of this earlier patent. However, particularly when a pulp mat is of considerable width, with the Well-known tendency of the edge portions of the traveling pulp mat to lose moisture more rapidly than the center portion, it is most desirable to be able to control the application of the steam to the mat proportionately across the respective areas of the mat instead of applying the steam equally over the entire mat as provided in the device of 'Pat. No. 2,838,982. Accordingly, the object of the present invention is to provide an apparatus for discharging dry steam down onto the mat, which apparatus will be composed of separate steam chambers, each separately and independently controlled, and so arranged that a desired proportionately greater amount of steam can be applied to the center portions of the mat than to the edge portions.

SUMMARY OF THE INVENTION The device is formed of a plurality of individual steam chambers, secured end-to-end so as to form a composite device extending transversely over the entire pulp mat passing beneath the device. The individual steam chambers are similar, being of the same width and transverse cross-section, with each chamber having a bottom wall formed into ridges and valleys, similar to the bottom wall in the device of the above mentioned US. Pat. No. 2,838,982, and thus with the steam from each chamber being discharged from orifices in the ridges in the bottom wall while the moisture from the steam in each chamber is collected in the valleys between the ridges. Means are provided for draining ofi the moisture collected in the valleys of the chambers separately, and the delivery of steam into the separate chambers is also separately controlled. The end chambers of the composite device are so arranged that the desired proportionately less steam can be discharged down on the edge portions of the pulp mat and a greater amount of steam discharged down on the center portion of the mat where most needed.

3,726,757 Patented Apr. 10, 1973 BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a foreshortened top plan view of a compos te steam chamber built in accordance with the present 1nvention, comprising an inner chamber and two end chambers, the composite device extending transversely above a traveling pulp mat;

FIG. 2 is a fragmentary sectional elevation taken on line 2--2 of 'FIG. 1, drawn to a considerably enlarged scale;

FIG. 3 is a foreshortened top plan view, similar in part to FIG. 1, of one of the end chambers of the composite device, but illustrating in part a modified construction of the device;

FIG. 4 is a fragmentary sectional elevation on line 4-4 of FIG. 3, drawn to the same scale as FIG. 2, with a portion of the transverse trough in the end of the inner chamber broken away for clarity;

FIG. 5 is a fragmentary and foreshortened longitudinal sectional elevation taken on line 55 of FIG. 3 and FIG. 4, drawn to the same scale as FIG. 4, with portions broken away for clarity;

FIG. '6 is a fragmentary section of FIG. 4; and

FIG. 7 is a fragmentary section taken on line 7-7 of FIG. 6.

Referring first to FIG. 1, the composite steam-applying apparatus as illustrated consists of three separate closed chambers, namely an inner chamber 10 and two end chambers 11 and 12, the end chambers secured to the ends of the inner chamber 10 respectively. All three chambers are identical in cross-sectional shape and size and together form a stationary composite apparatus extending entirely across the traveling pulp mat P, the apparatus being supported by suitable means (not shown) with the bottom of the apparatus spaced slightly above the pulp mat, which mat is carried along the Fourdrrnier wire F of the paper-making machine in the customary manner.

The bottom wall of each of the chambers 10, 11 and 12, like the bottom wall of the steam-applying device of the above mentioned US. Pat. No. 2,838,982, is formed into a series of V-shaped sections forming alternate ridges 13 and valleys 14 (see FIG. 2) extending from one end of each chamber to the other, the ridges lying in a substantially horizontal plane parallel to the Fourdrinier wire and the valleys 14 similarly lying in a horizontal plane except that the valley 14' at each side of each chamber is located below the level of the other valleys and extends to the plane of the bottom edge of the longitudinal side wall and the bottom edges of the end walls of the entire device. The ridges and valleys of all the chambers 10, 11 and 12 preferably are in alignment respectively. The end chambers 11 and 12 are secured to the inner chamber 10, preferably by having their inner end walls omitted and being welded instead to the respective end walls 15 and 16 of the inner chamber 10.

Along each of the top ridges 13 of the bottom walls of the three chambers a plurality of spaced orifices 17 are provided through which steam jets are directed down onto the pulp mat. In the two end chambers 11 and 12 the valleys 14 have drain outlets in the outer end walls which are controlled by drain taps 18 (FIG. 1) on the outside of the end walls, and similarly the lower valleys 14' in these two chambers are drained through drain taps 19.

In the form of the device shown in FIGS. 1 and 2, the valleys 14 of the bottom wall of the inner chamber 10 are drained by a central transverse cut-away pipe or trough 20 which intercepts the valleys. The ends of this taken on line 6-6 cross pipe 20 terminate in and discharge into the lower valleys 14' on the opposite sides of the chamber respectively, one of these ends being shown in FIG. 2. A cleanout plug 22 (one of which is shown more clearly in FIG. 2) is provided in each of the sides of the chamber wall in axial alignment with the corresponding end of pipe 20 as a convenience in aiding in the cleaning of the pipe 20 if for any reason this should becomes necessary. A sealed and locked inspection plate 23 and vacuum breaker (FIG. 1) is located in the upper side wall of the chamber 10. In order to drain off the water collected in the lower valleys 14' along each side of the inner chamer 10 and any water discharged into these valleys from the cross pipe 20, and therewith from the valleys 14 of the inner chamber 10, an outlet 24 is provided at the bottom of each side wall of the chamber 10 in the locatron shown in FIGS. 1 and 2. Each of these outlets is connected to a pipe 25 which extends longitudinally along on the outside of the chamber and continues along the outside of an end chamber (in this case end chamber 11, as shown in FIG. 1), to an outer end of the device, these pipes being supported by suitable brackets 26. A drain tap 27 is located at the end of each of these outside pipes.

Steam under pressure from a suitable source (not shown) is delivered by a pipe 10 through an inlet 29 (FIG. 1) preferably at the center of the top of the chamber 10 and is discharged throughout the interior of chamber 10, preferably through the intermediary of a pair of oppositely-directed nozzles in the chamber (indicated by the broken lines 30 in FIG. 1). Also steam from the suitable source is delivered into the chambers 11 and 12 through the pipes 11' and 12'. Suitable controls (not shown) are provided on each of the pipes 10', 11 and 12'.

Preferably, but not necessarily, a small orifice 31 (FIG. 2) extends through each end wall of chamber 10 at the termination of each valley 14 to allow some moisture at that end of the valley and a small amount of steam to be discharged into the adjacent chamber. The chamber 10 is provided with a safety blowout disc 32 to serve in the event that steam pressure in chamber 10 should for any reason build up in excess of the desired safety range. A pressure gauge (not shown) is also mounted on each of the chambers 10, 11 and 12. The end chambers 11 and 12 are also similarly provided with inspection plates and blowout discs (not shown).

Thus the dried steam, discharged down on the pulp mat passing along beneath the device or composite steam chamber, may be delivered proportionately on the pulp mat as desired with the greater amount delivered on the central portion of the mat where it is most needed, and with predetermined lesser amounts delivered down onto the edge portions as circumstances may require in order to aid in causing more uniform drying of the traveling mat across its entire width.

While the device is described as composed of a single inner chamber and two end chambers, it would be possible to have two inner chambers, joined end-to-end, with the two end chambers connected respectively to the outer ends of these two inner chambers. However, for all practical purposes, even for wide pulp mats, it has been found sufficient and satisfactory to have a single inner chamber and two end chambers, substantially as shown, with the length of the device made according to the particular papermaking machine and width of the pulp mat on which the device is to be used, and with the individual chambers made of various lengths as required. Also, it would be possible to have the inner end walls left on the end chambers 11 and 12 and to have the extending flanges of these walls bolted to the extending flanges of the end walls of the inner chamber 10, with suitable sealing gaskets therebetween, instead of having the end chambers welded to the end walls of the inner chamber 10. However, it is considered preferable and more practical to have the end chambers welded to the end walls of the inner chamber as described since ordinarily the device will be manufactured 4 specifically to suit a particular paper-making machine, and for permanent mounting thereon.

FIGS. 3 to 7 inclusive illustrate a modification in the construction of the device in which a transversely-extending trough at one end of the inner chamber 10 is used for disposing of the water collecting in the valleys 14 at the bottom of that chamber, in place of the cross pipe 20 previously described with reference to FIGS. 1 and 2. This transverse end trough (shown best in FIGS. 4 and 5) is formed by the end wall 16 of the chamber 10 and a downwardly sloping baffle wall 33 which slopes downwardly toward the end wall 16 and at the bottom is joined to the bottom of the end Wall 16. The top edge of this trough wall 33 conforms to the ridges 13 and valleys 14 forming the bottom of the chamber 10.

A drain opening 34 (FIGS. 4 and 5) in each of the valleys 14 of the chamber 10 is located near the end wall 16 of the chamber within the trough wall 33 so that any water collecting in the valleys 14 in the chamber 10 will pass down into the bottom of the trough thus formed.

In this modified form the end wall 16 of the chamber 10 is provided with a bottom aperture 35 at the end of each of the two lower side valleys 14', one of these apertures 35 being shown in FIGS. 4, 5 and 6. A pair of drain pipes 36, one of which is shown in the drawings, extending respectively along the corresponding lower side valleys 14 in the end chamber 12, have their inner ends extending through the corresponding bottom aperture 35 in the wall 16 of the chamber 10, and, as apparent from FIG. 6, carry off the water collected in the transverse trough at the end wall 16 of the chamber and in the lower side valleys 14' of the chamber 10. Each of these pipes 36 extends out through an aperture formed in the outer end wall 37 of the end chamber 12 and is controlled by a suitable drain tap 38. Thus, with this modified construction, all the water collected from the steam in the inner chamber 10 can be drawn olf through the two pipes 36 which extend through the end chamber 12 and it is not necessary to have any external drain pipe for the inner chamber 10.

As previously mentioned, each of the valleys 14 of the end chambers 11 and 12 is drained through a drain tap 18 on the outer end wall. In order to provide for drainage of the lower bottom side valleys 14 in the end chamber 12 with this modified construction, without interfering with the drain pipes 36 from the inner chamber, an inside opening 39 near the outer end of each of the side valleys 14' for the end chamber 12 leads into a small, closed compartment 40 which in turn discharges through an aperture 41 in the outer end wall 37 of the chamber 12 and is controlled by a drain tap 42, as shown in FIGS. 7 and 3. Only one of these end drainage compartments 40 is shown in the figures, but it is to be understood that the drainage compartment for the other lower side valley 14' for the chamber 12 is similarly arranged.

It will be possible, as previously mentioned, to have the device composed of two inner chambers, joined endto-end with two end chambers connected to the respective outer ends of the two inner chambers. In such case, with the employment of the modified drainage means, each of the inner chambers would have a transverse drainage trough at its outer end which would discharge through a pair of pipes located in the lower side valleys 14 of the adjacent end chamber. However, also as previously indicated, the forming of the composite steam chamber with a single inner chamber and a pair of independently controlled end chambers is considered adequate for any paper-making machine of present use.

In either case the incremental design and construction of the device makes it possible to apply the steam proportionately as needed and thereby constitutes a moisture profile control.

I claim:

1. In a paper-making machine in which a pulp mat is carried along on a Fourdrinier wire, a device positioned above the Fourdrinier wire and extending transversely J from one side of the wire to the other for discharging relatively dry steam down onto the pulp mat, said device comprising a plurality of separate steam chambers with means for delivering steam under desired pressures separately into each chamber, said chambers being of the same width and secured end-to-end, the bottom walls of said chambers being formed into a series of ridges and valleys extending from one end of each chamber to the other, said ridges and said valleys extending in planes parallel to said Fourdrinier wire, the ridges and valleys of said bottom walls of said chambers being in alignment respectively, the valleys at the side walls of said chambers lying in a plane slightly lower than the plane of the other valleys, each of said ridges in said bottom walls of said chambers having a row of steam jet openings dis charging downwardly onto said pulp mat, said chambers at the two ends of said device being similar, drains for said valleys in said bottom walls of said two end chambers mounted in the respective outer end walls of said end chambers, an inner chamber in said device located inwardly of an end chamber, a transversely-extending trough in the end of said inner chamber, said trough formed by a downward, obliquely-sloping wall joining the bottom edge of an end wall of said inner chamber, the top edge of said downward, obliquely-sloping wall conforming to the ridges and valleys in the bottom of said inner cham- 6 her, said valleys in said inner chamber, With the exception of the two lower valleys at the sides of said inner chamber, having discharge outlets opening into said trough, means defining a pair of outlet apertures in said end wall of said inner chamber at the ends of the lower side valleys respectively of said inner chamber, and a pair of drain pipes extending along in the side valleys of an adjacent end chamber and leading from said outlet apertures respectively, the outer ends of said drain pipes extending through the outer end wall of said latter mentioned end chamber, and a drain tap at the outer end of each of said drain pipes.

References Cited UNITED STATES PATENTS 3,669,831 6/1972 Dupasquier 162-290 2,838,982 6/ 1958 Dupasquier 162-290 X 153,139 7/1874 Wilmot 165-110 3,097,994 7/ 1963 Dickens et al 162-308 X S. LEON BASHORE, Primary Examiner R. V. FISHER, Assistant Examiner US. Cl. X.-R.

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