US2665843A

US2665843A - Centrifugal bowl with conical disks having distributing holes

Info

Publication number: US2665843A
Application number: US232492A
Authority: US
Inventors: Staaff Per Hilding
Original assignee: Separator AB
Current assignee: Alfa Laval Holdings Amsterdam AB
Priority date: 1951-06-20
Filing date: 1951-06-20
Publication date: 1954-01-12
Anticipated expiration: 1971-01-12

Description

Jan. 12, 1954 ITI-I CONICAL DISKS HAVING DISTRIBUTING HOLES Filed June 2O 1951 P. H. s'rAAFF 2,665,843 CENTRIFUGAL BOWL W INVENTOR. ber Wz'ldz'ng Szocf f XBYM, Y i??? Patented Jan. l2, 1954 UNiTeo sTATesp NT orric CENTRIFUGAL BOWL WITH CONICAL DISKS HAVING DISTRBUTING HOLES Per Hilding Staa, Bromma, Sweden, assignor to Aktiebolaget Separato 4: Claims.

This invention relates to an improvement in centrifugal bowls designed for the separation of sludge-containing liquids between conical discs in the bowl chamber, the discs having distributing holes for the liquid.

In the centrifugal separation of liquids containing a particularly sticky sludge, it has been found that sludge deposits are formed on the edges of the distributing holes of the discs at the side of the holes where the sludge passes through them, that is, usually the side which is closest to the periphery of the centrifugal bowl. When separating neutralized sour cream, for example, sludge is deposited on the outer edges of the distributing holes in the discs. These deposits may grow until they extend around the hole and may even finally clog it, but they may also cause a clogging of the inter-disc space closest to the holes. In this way, an unbroken sludge string may nally be formed, extending through all the superimposed distributing holes. As the number of holes in each disc is generally three to six, equidistantly spaced, they may become clogged to such an extent that the separating effect of the machine is reduced considerably. When separating sour cream, the separating effect may drop quite rapidly to nil.

According to the invention, this problem is solved by making the edges or rims of at least some of the distributing holes chamfered on that side where the sludge discharges through the holes. I have found that in this way even a very sticky sludge will pass through the distributing holes in the discs without the tendency to clog them. By reason of these charnfered edges of the disc holes, the sludge passing through the holes will have no holding points on which a core of deposition may be formed and grow, but the sludge will slide off or be cut off the edges, under the action of the centrifugal force in the bowl, and proceed between the discs.

The clogging of the holes in conventional discs of centrifugal separators usually starts between the lower discs. Depending upon the liquid to be separated, it may therefore be sufficient to chamfer the edges of only the first discs, reckoned in the direction in which the liquid passes through the holes.

The invention will now be described in more detail with reference to the accompanying drawing, in which:

Fig. 1 is a vertical sectional View of part of a centrifugal bowl, showing the outer part of a number of discs made according to the invention;

and

r, Stockholm, Sweden, a

Fig. 2 is a face view of a portion of one of the discs shown in Fig. 1.

In the drawing, the conical discs l are provided with distributing holes 2 through which the liquid to be separated ows in the direction indicated by the arrow. The sludge, being of greater specific gravity than the liquid, tends to move radially outward toward the peripheral wall d of the centrifugal bowl and therefore passes through the distributing holes 2 along the edges thereof nearest the wall li, that is, along the outer edges of the holes. These outer edges of the distributing holes are charnfered, as shown at 3. Thus, the holes present sharp outer edges 3 pointing generally radially inward toward the rotation axis of the bowl and away from the adjacent peripheral wall i of the bowl and the peripheral anges 5 of the discs. As a result, the sludge is prevented from depositing on these edges, due

to their radial-like disposition and their cutting action on the sludge under the centrifugal force in the bowl.

I claim: 1. In a centrifugal separator bowl containing conical discs provided with distributing holes, for

the separation of liquids containing sludge tending to clog the discs, the improvement which resides in at least some of the distributing holes, at the margins thereof where the sludge passes through the holes, being formed by chainfered edges of the discs, said chamfered edges forming sharp margins of the holes pointing generally radially of the rotation axis of the bowl and toward the opposite margins of the respective holes.

2. In a centrifugal separator bowl containing conical discs provided with distributing holes, for the separation of liquids containing sludge tending to clog the discs, the improvement which resides in at least some of the distributing holes being formed by chamfered edges of the discs at the outer margins of the holes nearest the adjacent peripheral wall of the bowl, whereby the holes present sharp outer edges pointing away from said adjacent wall.

3. In a centrifugal separator bowl containing conical discs provided with distributing holes, for the separation of liquids containing sludge tending to clog the discs, the improvement which resides in at least some of the distributing holes being formed by chamfered edges of the discs at the outer margins of the holes nearest the adjacent peripheral wall of the bowl, whereby the holes present sharp outer edges pointing away from said adjacent wall, said chamfered edges bef' ing provided on only the first few of said discs,

reckoned in the direction in which the liquid passes through the holes.

4. A centrifugal separator disc which comprises a conical disc body having distributing holes, the disc body also having chamfered edges forming the margins of said holes nearest the adjacent outer periphery of the disc, whereby the holes present sharp outer edges pointing away from said periphery.

PER HILDING STAAFF.

References Cited in the ille of this patent UNITED STATES PATENTS Number 5 802,150 1,731,999 1,870,608