US1284668A - Paper-machine. - Google Patents

Description

Patented Nov. 12, 9l8..

4 SIEETS--SHEEI 3.

A. 1. HAUS.

FAPea mmm.

APPLlCATON FILED JULY $3, ll, 1,284,668.

AY i, HMEG.

PAPER MASHHL APPLlcmxm: rmi; my; s.` i915 1 ,284,668. imma Nov. 12,1918.

4 sHE'ETsAaHEEI 2y A 1. HAUG.

PAPER MACHINE.

APPLacMmM r|LED1uLY13,1s16.

Patented Nov. 12, 1918.

4 SHEETS-SHEEI 3- [3Q/venia?? edition, JIIau/g.

A. l. HAUG.

PAiR MACHWE.

APPUCATIUN FILED mw :3.1916.

Patented Nov. 12, 1918.

4 SHEETSWSHEE 4.

1 and 2. To rotate the screen the latter is provided with suitablc driving mcnns such the driving pulley l5 tixcdly secured on one of the journal members such as i4.

The roller supporting' plates l2 may bc supported in any suitable manner but nre herein fixed on :i hollow` central, cylindrical member 16 which lorins n. fixed hollow coro extendingu the entire length of the seinen and is fasteni-ul noivrotntal'lly ut opposite ends of the .screen upon the ixed supports 17 and 18.

ln the described forni of screen the stock.

' is preferably delivcred to thc screening sur face under n coi'tain amount oiE impact, such for example ns would ariso from dropping it on the screcn. .Herein thc stoel: enters from any suitzibie minime oi supply :ind i|nder a suitnolo hond or 'prcssure through :i stock inlet pnssng'c. time end of the hollow. central. core pipe lo is herein utilized for the inlet, a stoot. inlet chamber 2U (Fig. l) being formed thc cnc', of thc, pipil am! iflgssdffby the pf 2,/ or partition wall 2l lr:- oated osit wat along; tlm pipe. This cimmbor Biff provided with s liilcrzil i'eed delliery opening 2:2 Fig? l and 2%) located www the descending sido nl the drains, the dirciflion] oi" rotation LoingA iziglitdianded in: viewed inllig. 3 and ns indicated by the arrow therein. Although iifn'iight extend for a greater length than ,sbim'ri7 for reasons hereinafter referred tm the delivery opcning i'cxtends forv a, iflstivcly short portion only of the length nl the drinn.

The stock entering the chamber 2O llows out thc opening? '22 on plato sind thence wer a curved( dollecting plate 24 (Figs. 3 and 'troni which it drops into im underlying pool ci' nt the drum und charges sich pcclst with :i Winntity of the stock' for dsnnuo ed il lo the length or" thu delivery da this druin rotates the il pass out'r of the wings im the next pooh-cl will no, and so on` as thc siiciirs presented in turn to the (lessive pockets delivery.

The stock bein 41f rlelivsred to the deseanding polict nt one of the finis ci rotation,

its impact sind weight assist in turning 'the drum. llhe imprint nl the stool: on the screen-ing surface ,is particularly effective in lit securing an ellicicnt smecnim; nctioin and es pecially so in the described form of screen Where it is irnnimliately followed by :in ngitiition of the srocli within the pocket1 Siicli agitation might be obtained by any moy@ ment of the serosning surface, but 'in the (inscribe/d form of screen is secured specit cally by the rotstionof the drinn It is fur ther intensified by the provisin and shape ot thc pockets the stool: "tendii'ig lli-st to strike tbeiiUderinoSr partition mill und slide down the snriieto thcliottonrof thc pocket Yoi said side. Wull when the elevation und in.

clinution of thc latter become suilicicnt.

The impact of the stock against the do Vscinidi-ng pocket Woll is facilitated by the curved, dcllecting plato 24 which accelerntcs the movement of the stock thercat. During tlic impact and agitation of the stool; within the pocket, the Screened stock passes ntf through the screening plates 5v into the underlying tank 25 and thence out through any suitable outlet 26 (Fig. G). The tailings or residuo :Irc automatically re moved from the pockets of the screen, this, in lrlie illustrated for l olT screen. being secured by thc gravitation of the tailings from the` pockets as the latter ascend during the rotation oi' the screen. As the pockets asccnd the unscrccncd residuo tends to drop out unassisted, although overhead shower pinos may bo cmployeifl to assist tliisinovelinut if fle-siicd.

in the illustrated forni of screen, following the described screening operation, the unscreencd residue is then again rescreencd and I'neferably subjected to impact and ngitation. similar to that described in the first screening, such rescreening being repented many times as required.

In the. described embodiment of the in-Y ventinin the tailings are applied to ai sec- `,nd screening surface by utilizing the gravity or bend produced by droppingr the tailout of tbc ascending pockets of the drum to force tlicin to n position Where they :irc nguin droppcd into the descending puck` ctw ot tlm ,sc-reign drinn and licrcin the descending pockets oi' the suine scrcen drum, but at un adviinci-,d point longitudinally llicrciiil.

ln. the illustratori forni of screen the tailings in gravitating out from the 'ocket are assisted by suitable detlccting evices to flow into the mouth of a passage which lends ngnin 'to tbc descending side of the drum, at which point the stock flows into the descending pockets' over a'deilccting plate similar to the preceding delivery or delecting plate E24, und forming in effect an extension of the plete 24. The overflowing' stock drops into tho successive pockets on the descending side of the drum as before, and the same opera4 tion is again repeated. an advanced section of the drum being utilized for this resereen- .innf the tailings.

xeferring to the specific details illustinted, the `c`. ,ril'i'iil pipe lor core lll hns formi-d beneath it a semi-cylindrical chiunbf-r suitably positioned lo form n succcssion of licliczil stock supply passages. Referring clcauinnr the Shower pipe o0, the laltcr has at each end eiplu '6:2 between which and the inner face of t e rotating end plate ol' the screen. there is a slightI clearance. Each plug is provided with a sin ll opening U3 vehich in one position of the screen may be brought into registration with a removable plug G-L in the end plate. By removing the plugs tl-l access can be had to the shower pipe for cleaning the saine. The normal leakage of the water through the opening (33 is uniniportant.

Then the rescreened residue reaches the last section or compartment. as the tailings are dischal'ged from the descending pockets they are deflected into a discharge passage (Figs. il and 5) and conveyed by the outlet spout 7l to an.\v suitable tank or rereptaele. The passage T0 is formed iu the upper part of the pipe 16 by means of the partition wall 58 referred to. For the (lclivery of the tailings the last overlying conveyer section is formed as shown in lfig. wherein it will be seen that the detleetm'plate 42 hns a corresponding and oppositelv directed plate the two plates being so located and arranged that vthe dropped tailings are conducted down nlo the chamber T0 around and about the water pipe 56 whiolr extends up through the end at' saidchaniber. The retaining plate 43 covers the space between the deficclor Til and the flat plate Blf so that all the tinal tailings are deposited in the hoppenlike receptacle presented by the dcliector plates 42! and 72. i

Referring lo Fig. 4. it will be seen that the several underlying convcycr sections are provided with small. rertangular.` fiat plates 35, 35, ett'. These extend to the edge of the rib ft2 in cach rase and prevent the tailings which are dropped in one compartment from entering the supply passage leading to the saine compartment. Similar plate 3G, 36, are provide to ovcrlic the ribs at the discharge ends of the several passages to prevent the stock fed lo the descending side (ff the drum in one eoinl'iartlncnt from entering' the supply passage for the next adjacent compartment.

It has been found that repeatedly screening the same stock gives a somewhat different grade of stock for successive screen ings. If it is desired to grade the stock according to the screenings, the tank 25 ma be provided with transverse partition wal s to' separate the stock screened in one compartment from that screened )in another, and transverse partition walls may also be provided withm the screen drum itself to se a rate the stock in one portion of a 'poc et frontn'the Stock portion of the same pocket. Such partition walls are not herein Shown, however` and for ordinary .purposes tliey`are not required in the screenldrum'smce the screening of the being rescreened in another' stock is so rapid that the stock in the dillerent portions ot' the same pocket tends to keep separated.

Ierforations of progressively decreasing size in the Screen plates might also be availed of as the stock passes through successive screening stages 1n the drum.` but forex# dinary purposes the plates may be the same as regards size of perforations in the different portions of the drum.-

It wlll be observed that in the described form of machine the stock'enterin one end of the screen drum is delivered to t e screenin;r surface under impact, is agitated thereon and Withdrawn therefrom. In a thinned down condition it is then subjected to a screening urder impact and agitation, this being followed if desired by as many suocessve screeningsas may be required.

lt will be observed that the bearings for the screen drum are open or exposed and accessible. Nevertheless, such provision is made that no oil from t e bearings can leak out and mingle with oit er the screened or the. unscreened stock, and revision is also made so that the unsereened stock or the Waste cannot mingle with the screened stock. this being accomplished Without the necessity of parkings. This end is attained by a system of cooperating, deflecting rings as :follows: Unscreened stock which tends to work toward the jointbetween the core 16 and the. drum head tends to be caught upon the circumferential shelf 80. whence it overflows into an annular channel formed by the disk-shaped plate 81 secured to the core and. gravitating to the bottom of that plate. flows bat-k over the edge of the channel into the screen drum. Such of the unscreened stock as may pass this barrier enters a chamber S2 between the bearing plate 1Q, but is prevented from entering the bearings by radial drain openings 83 in the chamber through which the stock gravitates into a position outside of the screened stock tank 25. Both nnsereened stock and any oil which may drop through the drain openings 83 is prevented from entering the screened stock" tank by means of the bell-shaped deflector 84, as well as the conical shleld 85. The latter also serves to throw baek into the tank for the screened stock any stock which may drop on the shield near the top thereof after having been carried up by the Vscreen drum itself.

While for pu oses of illustration I have f herein shown an described one specific embodiment of the invention, it is to be understood that the same is submitted for illustrative purposes `lonly and that extensive deviations may be made from the specc construction shown, the fdrm and relative ax'- rangement of parte and the specific application made of/ the invention, all without departing from the spiitthereof.

, ings.

Claims. i. A pulp screen for screening paper stock 1n stages comprising a screen drum, a central, cylindrical, fixed core having a semicylindrieal chamber beneath the same, end heads for the druin ioni-nailed about .said core, means for rotating the drum. a stock inlet passage entering the drum through one end of the core and having a lateral lei-d delivery opening extending for a portion only of the length of the drum and adapted to deliver stoel( therefrom on the dest-ending side ofthe drum. stock lifting platee secured to the interior ot the drum, the stoel; lit-ing screened and the` unscreened residue lifted and dropped h v said lifting hlades on the ascending movement of the latter` means for diluting the reSci't-ening the latter including conveying means` comprising a passage arranged heli cally around and beneath the cori',` in said seiniveylindrical chainher and having :in en trance to receive the diluted tailings from the preceding Cicreening, together with de tiecting walls to deflect' tailings thereto and having an exit opening at-a point aitialljT advanced lengthwise the drum from which the diluted tailings are delivered again to the descending side of the drum, thereby to subject them to a repetition o'f the screening and discharging action, means for siiccessively and progressively repeating the described dilution and rescreen'in as required, and means for withdrawing t e final vtail- 2. A pulp screen for screening paper stock in stages comprising a polygonal screen drum having flat. perforated blades forming the body or shell thereof, means for rotating the drum, means for delivering stock under impact to a screening surface thereof, said means comprising the stock inlet passage entering the drum and having a lateral feed deliver-iy opening located near one end thereof hut extending for a portion only of the length of the drinn and adapted to deliver stock therefrom on the descending side of the drum, perforated lifting blades se cured to the interior of the drum and cooperating with the shell ot' the drum to form a series of internal pockets adapted to agi tate and screen the stock during the. rotation of the drum, the unscreened residue being dropped out of the. pockets on the ascending movement of the latter, means for'diluting the thickened residue, means for i'escreeniug the diluted residue including conveying meansi'comprising a passage arranged in a helical nath and having an entrance to receive the diluted residue from the preceding screening'` and a discharge opening again to deliver the said residue upon the descending side of the drumVm at a point. axially advanced therein, thereby to subject. it to a repetition of the screening and dis thickened residue, means for4 charging action, means for successively repeating the described dilution and rescreening as desired while advancing the stock through the drum, and means for discharging the linal tailings.

Il. A pulp screen comprising a drum having stoel( lifting hlades, means for rotating the drinn. means4 lor deliverin stock Lo one und tin-roof whereh'v the stoci is screened and the residue lifted and dropped by the hlrzdes on tluascending movement of the latter. means for diluting the thickened residue, means for rescieenmg the diluted lrestidue including one or more passagesili' angeli in succession in a helical path and. tiring an entrance to receive the diluted4 tailings from the preceding screening, toGether-With delicrting walls to deflect` the iailingsfthewrg also a discharge'exitof) `in tailings agariiipon the Vwending blades oi: the drum atea pointfax in l I v ad vanced, therein thereby to siihjectit progr sively to neor more repetitions of he ,-:mee'uing and discharging action, and means to withdraw the ifinal tailings.

l. ,i rotary' screen haviiie stock lifting blades and means for redelivering to the screen the unsereened residue discharged from said blades and subjecting the same to a rcscreening action, the saine including .'i conveyer formed in sections aiidproviding one or more passages arranged in a helical path and havingnn entrance to receive the tailings from,tlie preceding screening, together with defiecting walls to deflect the tailings therein and havingalso a discharge exit opening again to deliver stock on the descending side of thedrum at a, point axially advanced therein. thereby to subject it to u repetition of the screening and dischargiing action, and means 'for withdrawing th:` final tailings.

li, A screen coin prising a drum, a central, evlindrieal, fixed core having a seinicvliiidrical chamber Leucath the saine, means for feeding stock to one end of said drum through said central core, means torl advanc-v in;r the unscreened residue through the drum and 'rescrcening the same by stages compris-- ing one or more passages arranged helically around and beneath the core in said semicylindrical chamber having an entrance to receive the tailings from the preceding screening and also a discharge exit opening again to deliver the stock to the drum thereh v to subject it to a repetition oli the screening action. and means for diluting the unscreened residue prior to the repetition of each .screening action. Y

6. A paper pulp screen having a rotary screen drum. a central, cylindrical core mem her. means for feeding stock to the drum` means for withdrawing the final tailings therefrom. and means for progressively adi :iin-ing the unscreened residue through the in. and having to deliver sai( ii t) drum comprising 'one or lmore conveyor pas sages arranged in a hehcal path and contalned within a chamber adjacent said core.

7. A rotary, polygonal screen. having stock lifting blades whereby the stock is screened and the residue lifted and discharged by gravity, and a succession of conveyinplr passages to yadvance the residue progressively and repeatedly through the drum to subject the same to a succession of rescreening actions, and means to withdraw the final tailings.

8. A paper stock screening apparatus com prising a rotary screen havin interior pockets, means for supplying stocilx to said pockets, means for rotating said member to cause the discharge of the unscreened residue as the pocket aseends. and means for delivering said unscreened residue again to the descend ing pocket of a. rotary screening member.

9. In a paper pulp screening apparatus, comprising a rotary screen drum, containing inwardly projecting lifting walls, means to feed stock to said drum, the unscrcened resiN due being lifted and discharged from the walls through the rotation of the drum, and means to subject the residue to a similar screening and lifting action.

10. In a paper pulp screening apparatus, the combination with av rotary screen drinn containing inwardly projectingliftin Walls, means to feed stock to the drum, l-ie unscreened residue being lifted and r'dnirged from the walls through the rotation of the drum, and means to subject the residue to a succession of simzlr screening and lifting actions.

1,1, The combination with a rotary screen containing' inwardly projecting lifting Itrlls, means to feed stock to said drum, the nscreened residue being lifted and discharged from the walls through the rotation of the drum, means to dilute the residue, means to cause the diluted residue to gravitate again upon the walls of the screen drum and to be subjected again to a similar screening and -lifting action whereby the un screened residue is advanced progressively through the drum. l

12. In a paper screening apparatus, the combination with a rotary screening drum provided with foraminous lifting blades, stock delivery means for delivering,l stock upon said blades, the same being screened. lifted and the residue drop ed by the rotation of the drum, means ihr diluting the residue, delivery means to deliver the diluted residue again to the drum at a point advanced lengthwise theV same to provide for a repetition of 'the screening and lifting operation and subject the unscreened residue to a repetition of said screening, lifting and diluting actions.

13. A rotarv screen drum provided with foraminous lifting` blades, means to deliver lifting blades,

stock being screened and ythe stock to the saine, the same being screened, lifted and the residue dropped by the rotation of the drum, delivery means to convey and drop the diluted residue again upon the drum-and the blades at a point advanced lengthwise the same to provide for a succession of repetitions of said screening, liftN ing and diluting actions.

14. A rotary screen drum having stock lifting` blades, means for feeding stock to one end of said drum, the stock so fed being screened and the residue lifted and discharged by said blades, and'means to deliver theun screened residue discharged from said blades againto the said blades at an advanced point in said drum.

15. A rotary screen drum having `steelt: lifting blades, means for feeding stoel: to one end of said drum, the stock so fed being screened and the residue lifted. and dieu charged by said blades, and n'ieans a, aiu to deliver the unscreeued residue dise rged from said blades to the' drum at an advanced point lengthwise the saine and subjecting said residue to a, further screening; and liftAV ing,r action.. i

16. A. rotary screen drum having stock lifting blades, means for feeding stock there to, said stock being screened and the residue beingscreened, lifted and dropped through. theJ rotation of the drum, means to dilute the residue, and conveying means to convey the same to another position lengthwise the drum, and a' repetition of the screening and lifting action. i

1-7. A rotary screen drum havin stock means for feeding sto@ thereto, said stock being screened and the residue lifted and dischargedv by said blades, means within said drum for diluting the said residue, and means for rescreening and ,lifting the diluted residue.

18. A rotary screen drum having blades, means drum on the liitn to deliver stock within said descending side thereof, the -the residue and discharged from said blades, andmeans to convey the residue to said drum again. on the descending side thereof.

, 19. A rotary liftingr blades,

means to deliver stock within the drum on the descending side thereof, stock being' screened and the residue lifted and discharged by said blades through the rotation ofthe drum means to'dilute the unscreenedresidue an conveyiugmeans to cnvey the daute ,residue t a. point lengthwise advanced on' the drum and drop the same again on the descending side thereof.

screen drum having stock",4

lila

l) Il 20. A pulp screen for screening paper stock comprising a polygonal screen drum having fiat, perfora walls forming the body or shell thereof, and stock lifting plates within the drum, a central, lixed, cylindrical core, end heads for the drum by which the same is jonrunled upon said lined core, end menne` for delivering stoel; into the drum through said core.

El. A pulp Screen for screening paper stock comprising a polygonal screen drinn haring flut, perlorntecl wells` forming the body or shell thereof, stock lifting plates within the llruiu, a central, lixed, cylindrical Core, end heathA for the clruni bj." which the Senne is jonrrmled upon said fixed core, nieuw,Y for dnliveriug noel; into the drum through said core, nud meanl'or" withdrawing the tailings from the opponit'e end of the drum abo through mid core,

rotar)v erreen drum having :lyceutral. cl\l'lindri alL lixeil corei drum hedgl al,

oppmitf.- end` ol' the drum. journal ,ljearinglfef for uid drum health` null `atorl: leerling.; menue within the core.

Ll. A rotary eea-een having foraniinous storia lifting hindi-e forming interior poelets. within the `eamo. menue` for delivering noch within said drum, a head nl each ul.'- poeilc und oF the Ilrunl, :and jou naled bearing on which will heznlaare mounted.

24;. A rotar)` `erw-n heringiueann for di livering iol-li within the miur nl one side of the axle thereof, alul a curved lleloeting plaie lo :vzcelrratr the delivery of the stock thereto.

25. A rotary .Qcrcrz'n having interior stock lifting blades5 menue 'for rotating the screen, menne to deliver Stoch lo the descending' side of the screen. und a curved drflectin plate lo nmzelernlr the delivery Ot' the stonk creto.

2lb A rotary S'r'ecn drum haring nn end lived at (inch end, piumini bre'ringge upon wlxieh Said heads nre mounted rotatably 'to support the drone a pulp upply inlrlwrntering; said drum through Ille lar-:wing al one will, a tailings discharge pz'iseat'nthrough llwheariugat 'lluw'xpponile und1 and a `honor water discharge dei icc aleo within the drum.

2T. A rotary screen drinn having end heads. journal bearings upon which mid heads nre jonrnnlcd rotatably to support the drinn, a hollow member extending: into tho drinn through our of said bearings; and containing n ailng rlirmbarjr 5mn-:enojo and n White Water discharge device nlm within the drum and rommuniraling' *with `aourre of supply oleo in Said hollow membri'.

QR. A rota-ry Screen drum having a shower pipe ied within the flame, menne i'or eupi'ilfinr; @bowler water thereto. eurl heads for `Laid rlrniu, said Shower pipe having an open end located in cloee px'oxmit)Y to the Walls of one of said bende, and a cleaning; opening in eaid bead adapted to be brought info reg'- istration with the cnil of Enid pipe.

29. ln a (il-vire of the el: Se llrnm'ilofl, the combination with a rotary: screen flrulu of open journal bearings: 4for `nid drum, a

Screened stock outlet, sind deflector plates to prevent the entrance of oil from the bearing into the screened Stock.

30. In a device of the clans described, the

combination with a rotary Screen drum, a fixed bearing member around Winch said drinn rotates, leaving a joint between the drum and the xrd bearing member ex osed to the interior of the screen, and de octor plates to prevent the exit of uneereened stock through thejoint between Said drum and mid fixed member.

31. l'n :in apparatus of the class de'ScIibed, the combination with a rotary Screen drum of :a fixed member aboutwhich said drum rotates. defleetor plates to prevent the exit of the unscreened Stock from the joint between Said drum and Said 'lx'ed member, means lo withdraw the stock facing said deveyed stock away from the screened Stock outlet.

3Q. ln n pulp screen, the combination of a wrecn drinn? a stock inlet, menne for utilizfleeting platee.. :md means to deflect the coning the head of the stock to turn the drum,

and menne 'For again applying 'the funscreened roeiflne to the screen and utilizing the saule to aseist in turning the drum.

33. ln a pnlp'ecreen the combination with a rotary screen drum of a stock inlet, means for repeatedly directing the stock against the drum to utilize the head thereof to turn the drum.

554, ln a pulp screen, the combination with n rotary screen drinn of a stock inlet and means for applying the stock and again the unscreenerl residue to the drum at one 51de of the axle of rotation thereof to exert a rotarnixnmlling eli'ect upon the drum. l

` l'n e pulp screen. the combination with 105` n rotary screen` a pulp inlet, memis todilute the unecreened `residue and mii'ltopply screened nud inclini-ged, further rotary 116 eerrening nurture also nroil'ided with pockets lo which the flier-named residue is elivered, :nul menne for repeatingr the Screen and lifting operation. i

37. A 'rotary `Teaming drum havingpock- 120 et. menne for delivering stock to said pockvla4 nhereb the @toch is agitated. lifted and diecharmwl` and means to receive the discharged residuo and divert it to' pockets in a different parl of said screen for a repetition of the Screening operation.

38. A pulp screen for screening vpaper stock in etages. comprising* a. ieci-een drum, #och lifting Walle Secured to the interior of the drum. means. for rotating the drum whereby the stock is screened and the unstock in stages, comprising a screen drum, screened residue lifted and dropped by said stock lifting walls secured te the interior lifting Walls' means for diluting the thickof the drum, means for rotating the drum ened residue, means for rescreening the lntwhereby the stock is screened and the un- 30 l5 ter, includi means to receive the disscreened residue lifted and dropped by said charged resi ue and divert and deliver it to lifting walls, means for diluting the thickpockets in said drum at a more advanced ened residue, means for rescreening the latu point therein for .a vrepetition of the screenter, and means for progressively repeating mg and discharglng action, and means for the described dilution und rescreening as re- 35 10 progressively repeating the described'diluquired.

tion and rescreening-us required. 41. A pulp screen for screening iaper f 39. A pulp screenA for 'screening paper stock in stages, comprising a screen rum, stock in stages, comprising a screen drum, stock lifting walls secured to the interior of stock lifting Walls Secured to the interior the drum means for rotating the drum 40 l15 of the drum, means for'rotating the drum whereby the stock is screened and the unwhereby` the stock is screened and the unscreened residue lifted and dropped by said screened residue lifted and dropped by 'said lifting walls, means for diluting the thicklifting walls, ,means for rescreening the ened residue, and means for rescreening the thickened residue, including meansto receive latter, including means to ive the dis- 45 2u the discharged residue and divert and decharged residue and divertiiidelivepitto,

liver it to pockets in said drum at a more pockets in said drum at 9.,:m0r`e' advanced advanced point therein for a repetition of point therein for a, repetition eff-the the screening. and discharging action,` and :ligand discharging action. means for progressively repeating the cle-z 25 scribed dilution and rescreening. as required. name to this Specification l 40. A pulp screen for screening paper ANTON J. HAUG.

n testimony'nwherenfhave signed 50`

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