SE201449C1

SE201449C1 -

Info

Publication number: SE201449C1
Authority: SE
Publication date: 1965-01-01

Description

KLASS INTERNATIONELLSVENSK B23 n49 1:12 PATENT- OCH REGISTRERINGSVERKET Ans. 92411963 inkom den 28/1 1963 iillagd den 20/4 196 SOCTTETE. DES POUDRES MeTALLIQUES ET DES ALLIAGES SPECIAUX UGINE-CARBONE, PARIS, FRANKRIKE Satt att framstfilla porosa filterelement Uppfirmare: R Meyer och P Potet Prioritet begtird frcln den 5 februari 1962 (Frankrike) Foreliggande uppfinning hanfor sig till sammansatta, porosa kroppar av sintrade metaller och ett salt att framstalla sadana. CLASS INTERNATIONAL SWEDISH B23 n49 1:12 PATENT AND REGISTRATION AGENCY Ans. 92411963 was received on 28/1 1963 iillagd on 20/4 196 SOCTTETE. DETAILS OF METALLICS AND OF ALLIAGES SPECIAUX UGINE-CARBONE, PARIS, FRANCE Set to produce porous filter elements Inventors: R Meyer and P Potato Priority started from 5 February 1962 (France) The present invention relates to composite, porous bodies and sintered bodies. salt to produce such.

Porosa, sintrade metaller anvandas for olika andamal, exempelvis for filter. De vanhiga, homogena ifilterkropparna besta av ett material med homogena egenskaper utefter hela den bana, langs vilken den filtrerade produkten skall passera, fran filtrets intradessida till dess uttradessida. Fir en given tjocklek pa filterkroppen blir tryckforlusten i kroppen desto hogre ju mindre porerna aro, dá finare material skall avskilj as. Tryckforlusten kan aven bli prohibitiv. Porous, sintered metals are used for various purposes, for example for filters. The conventional, homogeneous filter bodies consist of a material with homogeneous properties along the entire path along which the filtered product is to pass, from the inlet side of the filter to its outlet side. For a given thickness of the filter body, the pressure loss in the body becomes higher the smaller the pores, the finer material must be separated. The loss of pressure can also be prohibitive.

Det liar ftireslagits, -att man skulle framstalla sammansatta, porosa kroppar genom att sintra ett mycket fint och mycket taut, porOst skikt avsatt pa ett metallunderlag, som sjalvt är porost och liar sintrats for att tjanstgOra som underlag. Det är emellertid wart att astadkomma en saker fog mellan det tunna skiktet och metallunderlaget. It has been suggested that composite, porous bodies be produced by sintering a very fine and very tough, porous layer deposited on a metal substrate, which itself is porous and is sintered to serve as a substrate. However, it is wart to achieve a things joint between the thin layer and the metal substrate.

Foreliggande uppfining hanfor sig till ett satt att framstalla porosa filterelement bestaende av minst tva porosa metallskikt .med inbordes olika porositet, genom att flera pa varandra lagda skikt bestaende av en pasta bildad av ett metallpulver och ett bindemedel laggas pa varandra, varvid de pulver, som anvandas !for varje skikt, best. av kora Mom snava granser, och sattet kannetecknas darav, att de pa varandra liggande skikten, som bidda ,ett ,amne, forbindas med varandra genom en kallbearbetning for uppnaende av den Onskade tjockleken fOr det tunnaste skiktet, varvid bearbetningen sker utan minskning av volymen genom sattning hos metallkornen, och att de pa varandra liggande pastaskikten sintars samtidigt. The present invention relates to a method of producing porous filter elements consisting of at least two porous metal layers, with different porosity being embedded, in that several superimposed layers consisting of a paste formed of a metal powder and a binder are superimposed, the powders being used! for each layer, best. of short Mom narrow boundaries, and the manner can be characterized by the fact that the superimposed layers, which bidda, ett, amne, are connected to each other by a cold machining to obtain the desired thickness for the thinnest layer, the machining taking place without reducing the volume by settling of the metal grains, and that the superimposed pasta layers are sintered at the same time.

Kallbearbetningen kan utgOras av valsning eller sprutpressning och ,elementet .kan under sintringen lianas i en badd av inert pulver, exempelvis av aluminiumoxid. Det finaste pulvret bestar limpligen av kern av storleken 1-A. The cold working can consist of rolling or injection molding and, during sintering, the element can be lined in a bath of inert powder, for example of alumina. The finest powder consistently consists of kernels of size 1-A.

Vid kallbearbetningen andras salunda ,ej nrarkbart den av pastan upptagna totalvolymen. Ej heller tranger de olika skikten in i varandra i nagon namnvard grad. In the cold processing, others' salunda, not noticeably the total volume occupied by the paste. Nor do the different layers intrude into each other to any nominal degree.

De for de olika skikten anvanda pulvren kinma besta av olika material, forutsatt att dessa ha ungefar samma sintringstemperatur, sh aft en effektiv fog astadkommes vid gransytan under sintringen. Man foredrar emellertid ofta att anvanda pulver, som besta av samma material. F8r att de st8rsta fiirdelarna med uppfinningen skola uppnas, bör varje skikt ha sin kornfordelning. The powders used for the different layers can consist of different materials, provided that they have approximately the same sintering temperature, so that an effective joint is achieved at the spruce surface during sintering. However, it is often preferred to use powders, which consist of the same material. In order to achieve the greatest advantages of the invention, each layer should have its own grain distribution.

Bindemedlet kan utgoras av nagot av de vanligen anvanda bindemedlen for framstallning av sintenfilter genom strangpressning, dragning eller valsning, exempelvis paraffiner, vaseliner, fetter eller plaster. The binder may be any of the commonly used binders for making sintered filters by extrusion, drawing or rolling, for example paraffins, vaseline, greases or plastics.

Det sammansatta amnets form oeh det anvanda formningsfOrfarandet fOr uppnaende av slutproduktens onskade form hero uppenbarligen pa denna sistnamnda. Vid framstallning av plattor avsatter man pa ett relativt tjockt skikt av en f6rsta pasta forst ett eller flera tunnare skikt av andra pastor. Alla skikten bring-as sedan att hafta samman och bibringas onskad tjocklek genom valsning. Man kan salunda utgâ frau ett sammansatt amne, soul sedan valsas. For erhallande av sammari- 2 satta ror kan man bilda ett amne bestaende av koncentriska ringar framstallda av olika pastor, varvid den innersta ringen kan vara massiv, varefter amnet strangpressas eller drages. The shape of the composite blank and the molding process used to achieve the desired shape of the final product are obviously similar to the latter. When making plates, one or more thinner layers of other pastes are deposited on a relatively thick layer of a first paste. All layers are then brought together to stick together and imparted the desired thickness by rolling. One can thus proceed from a compound subject, soul then rolled. To obtain composite tubes, a blank can be formed consisting of concentric rings made of different pastes, whereby the innermost ring can be solid, after which the blank is extruded or drawn.

Sintringen genomfores sedan vid lamplig temperatur och pa lampligt satt. Man kan exempelvis tillampa ,det forfarande, som beskrives i den franska patentskriften 1.266 497. The sintering is then carried out at the appropriate temperature and in an appropriate manner. One can apply, for example, the process described in French Patent Specification 1,266,497.

De ,enligt nppfinningen framstallda, poriisa kropparna besta av tva eller flera porosa skikt, som ha olika pordimensioner. De olika skikten kunna ha ungefar samma eller mycket olika tjocklek. Enligt uppfiningen kan man exempelvis framstalla kroppar besthende av mycket tunna skikt och tjockare skikt, av vilka ,ett underst5djer det eller de tunnare skikten. De tunna skiktens tjocklek kan vara mycket liten, exempelvis 0,1 mm eller mind-re. De enligt uppfinningen framstallda kropparna utmarka sig vidare for en stark fog mellan de inga.ende skikten, som aro utomorclentligt homogena, emedan skikten joke tranga in i varandra. The porous bodies produced according to the invention consist of two or more porous layers, which have different pore dimensions. The different layers can have approximately the same or very different thickness. According to the invention, it is possible, for example, to produce bodies consisting of very thin layers and thicker layers, of which one supports the thinner layer or layers. The thickness of the thin layers can be very small, for example 0.1 mm or less. The bodies produced according to the invention further stand out for a strong joint between the constituent layers, which are extremely homogeneous, since the layers jog into each other.

Sattet enligt foreliggande uppfinning gOr det mojligt att framstalla sammansatta, por8- sa kroppar med Oka former, exempelvis skivor eller ror, varvid ett eller tvd ytterskikt kunna vara mycket fina, medan .ett grovre skikt svarar for kroppens mekaniska hallfasthet. The method according to the present invention makes it possible to produce composite, porous bodies with different shapes, for example discs or tubes, whereby one or two outer layers can be very fine, while a coarser layer is responsible for the mechanical half-strength of the body.

De enligt foreliggande uppfinning framstallda kropparna kunna bilda material med tva aktiva sidor, olika pordimensioner och for olika andamal, exempelvis i bransleceller. De kunna aven anvandas som filterelement. I detta fall bestammer det fina skiktet pa grund av sina egna egenskap.er de onskade filtreringsegenskaperna. For jamforelse mellan ett filterelement air vanligt sintermaterial och ett element framstallt enligt foreliggande uppfinning kunna lamnas foljande siffror: ett homogent filterelement for rening av gas belastad med fint stoft maste ha en avskiljningsgrans under 1 pin och samtidigt en tjocklek av 2 mm medfor en tryckforlust air 5 g/cm2 for en genomsattning av 40 m3/h och m2, medan ett element framstallt enligt foreliggande uppfinning loser samma problem med en tryckforlust air endast 1 g/cm2. The bodies produced according to the present invention can form materials with two active sides, different pore dimensions and for different purposes, for example in industry cells. They can also be used as filter elements. In this case, the fine layer due to its own properties determines the desired filtration properties. For comparison between a filter element air ordinary sinter material and an element manufactured according to the present invention the following figures can be left: a homogeneous filter element for purification of gas loaded with fine dust must have a separation distance below 1 pin and at the same time a thickness of 2 mm g / cm2 for a throughput of 40 m3 / h and m2, while an element manufactured according to the present invention solves the same problem with a pressure loss air only 1 g / cm2.

Exempel 1. Detta exempel .hanfor sig till framstallningen air ett sammansatt filterelement av brons. Detta element har ett c :a 0,5 mm tjockt filterskikt bestaende av korn med en medeldiam.eter av 20 ,um, och ett c :a 2 mm tjockt stodskikt bestaende av mycket grovre korn. Example 1. This example refers to the preparation of a composite bronze filter element. This element has an approximately 0.5 mm thick filter layer consisting of grains with an average diameter of 20 .mu.m, and an approximately 2 mm thick support layer consisting of much coarser grains.

Genom blandning framstalles var for sig: dels en pasta innehallande 93 viktprocent bronspulver med stariska korn och en diame ter av 10-30 ,uni, och 7 viktprocent blandning av 40 % paraffin och 60 % vaselin, dels .en pasta innehallande 92 viktprocent bronspulver med en korndiameter av 50-100 yril och 8 % av samma bindemedel som den forsta pastan. The mixture is prepared separately: a paste containing 93% by weight of bronze powder with staric grains and a diameter of 10-30, uni, and 7% by weight of a mixture of 40% paraffin and 60% petrol, and a paste containing 92% by weight of bronze powder with a grain diameter of 50-100 yril and 8% of the same binder as the first paste.

I en kvadratisk behallare med kantlangden 75 mm satsas erforderliga mangder av vardera pastan for bindning av ett sammansatt amne bestaende av ett c :a 15 mm tjockt skikt av det fina pulvret och ett c :a 60 mm tjockt skikt av det grovre pulvret. In a square container with an edge length of 75 mm, the required amounts of each paste are charged for bonding a composite blank consisting of an approximately 15 mm thick layer of the fine powder and an approximately 60 mm thick layer of the coarser powder.

Behallaren placeras i en strangpress med en lutning av 30° och forsedd med ett munstycke med en rektangular Oppning med bred-den 75 mm och hojden 2,5 mm. The container is placed in an extruder with a slope of 30 ° and provided with a nozzle with a rectangular opening with a width of 75 mm and a height of 2.5 mm.

Efter strangpressningen skares den erhallna plattan till 250 mm langa band, som lag-gas pa platar av rostfritt stal, tackes med aluminiumoxidpulver och sintras i vatgas, m.edan temperaturen langsamt hojes till 725° G. After extrusion, the resulting plate is cut into 250 mm long strips, which are layered on stainless steel plates, filled with alumina powder and sintered in water gas, while the temperature is slowly raised to 725 ° G.

Pa detta salt erhalles en filterskiva bestaende av ett 0,5 mm tjockt filterskikt pa ett 2-mm tjockt, porost skikt av mycket grovre korn. Denna platta Sr i stand att avskilja 'korn med en diameter under 1 fan och har sadan permeabilitet, att man med en tryckminskning air 5 g/cm2 uppnar en luftgenomsattning av 15 a/h och cm2 filteryta, och en bojbrottgrans air 2-5 kp/mm2. On this salt a filter disc is obtained consisting of a 0.5 mm thick filter layer on a 2-mm thick, porous layer of much coarser grains. This plate is capable of separating grains with a diameter below 1 fan and has such a permeability that an air permeation of 15 a / h and cm2 of filter surface is achieved with a pressure reduction of air 5 g / cm / mm2.

Ett lika tjockt filterelement bestaende air ,det finaste pulvret och med samma avskiljningsgrans har daremot fjardedelen sa hog genomsattning. Om .elementet ,framstalles av det grovre pulvret, far det dubbelt sa hog genomsattning sorn det sammansatta elementet, varvid dock avskiljningsgransen ligger fern ganger hogre. An equally thick filter element consisting of air, the finest powder and with the same separation margin, on the other hand, has a quarter as high a throughput. If the element is produced from the coarser powder, it has twice as high a permeability as the composite element, whereby, however, the separation limit is four times higher.

Exerapel 2. Detta .exempel hanfor sig till framstallningen av ett sammansatt ror av sintrad nickel. Man anvander nickelpulver utvunnet ur nickelkarbonyl och bestaende av korn mellan 1 och 15 urn. Detta pulver uppdelas genom slamning pa tva komfraktioner, namligen en pa 1-5 ,um och en pa 5-16 pm. Man erhaller ungefar 1 viktdel fint pulver pa ungefar 4 viktdelar grovt. Example 2. This example relates to the preparation of a composite tube of sintered nickel. Nickel powder extracted from nickel carbonyl and consisting of grains between 1 and 15 μm is used. This powder is divided by slurry into two fractions, namely one of 1-5 microns and one of 5-16 microns. You get about 1 part by weight of fine powder to about 4 parts by weight of coarse.

Till vardera fraktionen sattes en blandning av vaselin och paraffin for bildning av en pasta. Man framstaller sedan .ett cylindriskt med ytterdiametern 50 mm sammansatt air en central karna med diametern 22,4 mm och bestaende av fint pulver och en cylindrisk mantel av det grovre pulvret. To each fraction was added a mixture of petroleum jelly and paraffin to form a paste. A cylindrical with a outer diameter of 50 mm is then composed of a central core with a diameter of 22.4 mm and consisting of fine powder and a cylindrical jacket of the coarser powder.

For att erhallla ett sadant amne kan man anvanda olika apparater. Man kan exempelvis axiellt i en cylinder till en strangsprutmaskin med diametern 50 mm placera en metalldorn, vars ytterdiameter svarar mot diametern pa. 3 den 8nskade karnan, varefter man gjuter pas-tan av det grovre pulvret. Da pastan har stelnat, drar man ut metalldornen och gjuter den av det finare pulvret ,framstallda pastan i det kvarldmnade halrummet. To obtain such a subject, one can use different devices. For example, axially in a cylinder of an extruder with a diameter of 50 mm, a metal mandrel can be placed, the outer diameter of which corresponds to the diameter pa. 3 the desired karnan, after which the paste of the coarser powder is cast. When the pasta has solidified, the metal mandrel is pulled out and it is cast from the finer powder, the pasta produced in the remaining cavity.

Sedan det erhallna, sammansatta amnet har svalnat, drages det genom en vertikal dragskiva forsedd med en dorn. Pa..detta salt erMies en produkt med ytterdiaraetem 20 mm och innerdiametern 19 mm och en vdgg sammansatt av ett 0,1 mm tjockt innerskik't bildat av det fina pulvret och ett 0,4 mm tjockt ytterskikt bildat av dot grovre pulvret. After the resulting composite blank has cooled, it is pulled through a vertical pull plate provided with a mandrel. On this salt is a product having an outer diameter of 20 mm and an inner diameter of 19 mm and a wall composed of a 0.1 mm thick inner layer formed of the fine powder and a 0.4 mm thick outer layer formed of the coarser powder.

Den salunda erhallna produkten kapas till c:a 300 mm langa r8r, vilka placeras vertikalt i en JAM av aluminiumoxid och sintras under vatgas genom langsam varmning tll 850° C. The product thus obtained is cut into approximately 300 mm long tubes, which are placed vertically in a JAM of alumina and sintered under hydrogen gas by slow heating to 850 ° C.

Pa detta satt erhallas ror med tva homogena skikt, som aro fullstandigt hopsvetsade och ha olika filtreringsegenskaper. In this way, tubes are obtained with two homogeneous layers, which are completely welded together and have different filtration properties.

Foljande tabell utgor en sammanstallning av varden erhallna med sammansatta ror och homogena rOr med samma vaggtjocklek framstallda av ,ett icke sorterat pulver och av de bagge kornfraktioner, som erhallas vid sorteringen. The following table is a compilation of the cairns obtained with composite tubes and homogeneous tubes with the same rock thickness made of, an unsorted powder and of the ram grains obtained during the sorting.

Den sintrade vaggensPerme- GrOvsta sammansattningabilitet per i vid 1 0-8 pm cm2 Ror .enligt uppfinningens bestaende av ett 0,1 mm tjockt skikt av korn pa 1-luM och ett 0,4 mm tjockt skikt av korn pa 5-16 ftm.0,2, Homogena ror: vdggtjocklek 0,5 mm och fram- stallda av korn pa 1-16 an 0,9 vaggtjocklek 0,5 mm och fram- stallda av korn pa 1-5 yin0,02, vaggtjocklek 0,5 ram och fram- stallda av horn pa 5-16 urn. 0, De angivna vardena pa permeabiliteten svara mot Darcys koefficient, som beraknas enligt ekvationen.: U.71.L P =it. A i vilken U är genomsattningen, A är Ifiltreringsarean, L är filterelementets tjocklek, den filtrerade vatskans dynamiska viskositet och A p tryckf6rlusten i filterelementet. The sintered cradle Permea- GrOvsta compositionability per i at 1 0-8 pm cm2 Ror, according to the invention consists of a 0.1 mm thick layer of barley at 1-luM and a 0.4 mm thick layer of barley at 5-16 ftm. 0.2, Homogeneous tubes: wall thickness 0.5 mm and made of grains of 1-16 and 0.9 rock thickness 0.5 mm and made of grains of 1-5 yin0.02, rock thickness 0.5 frame and made of horns of 5-16 urn. 0, The stated values of the permeability correspond to the Darcy coefficient, which is calculated according to the equation .: U.71.L P = it. A in which U is the permeation, A is the filtration area, L is the thickness of the filter element, the dynamic viscosity of the filtered liquid and A is the pressure loss in the filter element.

Den storsta porens diameter bestammes bulloskopiskt. The diameter of the largest pore is determined bulloscopically.

Av tabellen framgar, att vid lika stora porer filterelementet enligt uppfinningen liar fyra ganger s8 hog permeabilitet som ett homogent element framstallt av ett pulver med samma kornfordeining som det finkorniga skiktet i det sammansatta .filterelementet. The table shows that with equally large pores the filter element according to the invention has four times as high permeability as a homogeneous element produced from a powder with the same grain distribution as the fine-grained layer in the composite filter element.

Claims

Patent claim:

A method of producing porous filter elements consisting of at least two porous metal layers of mutually different porosity, in that several superimposed layers consisting of a paste formed of a metal powder and a barrier agent are superimposed on each other, the powders being applied to each layer , consisting of barley Mom narrow borders, characterized by the fact that the superimposed layers, such as Janda a blank,, are connected to each other by a cold working to obtain the desired thickness of the thinnest layer, the processing taking place without reducing the volume by setting of the metal grains, and that the superimposed pasta layers are sintered at the same time.

2. According to patent claim 1, it can be stated that the cold working consists of rolling or injection molding, and that the element is kept in a bath of inert powder, for example of alumina, during sintering.

3. According to patent claim 1, it is claimed that the finest powder consists of horns of size 1-in. Request publications: