DE8717727U1 - Hydrocyclone or hydrocyclone parts - Google Patents

Abstract

1. Hydrocyclone or hydrocyclone parts consisting of a hard supporting outer layer of synthetic material and a comparatively softer inner layer of synthetic material, characterised thereby, that the outer layer (7) consists of a relatively hard polyurethane and the inner layer (8) consists of a comparative softer polyurethane more resistant to wear and that the outer layer (7) and the inner layer (8) at their common transition or contact surfaces (9) each stand in a cast bond with the other.

Description

DIPL-INQ. BERN HARD RICHTER.·' · 'j \. ^: · /\rf50dNÜRNBERQ80.den 20.12.198i PATENT ATTORNEY «&Lgr;,&bgr;^*,·»«»»» ^n/VD IcIe)(IdIIiM: Ritri

authorized representative at the European Patent Office Telex: 023a» pawd

European Patent Attorney ^{TeWax: 4} » ^mn > s** ⁸⁴ * ">·" ⁺ '" ^u *«"«>

Company AKW Apparate and Process GmbH Georg Schiffer Str. 70, 8452 Hirschau

"Hydrocyclone, or hydrocyclone parts"

The invention relates to a hydrocyclone or hydrocyclone parts according to the preamble of claim 1. In known hydrocyclones or hydrocyclone parts of this type, the outer layer consisted of a steel shell and the inner layer of a relatively soft polyurethane. This is disadvantageous in several respects. The production of such a steel shell or layer is quite expensive. The steel shell is very heavy due to the use of steel, which increases the overall weight of the hydrocyclone accordingly. However, such a weight hinders assembly and any repairs in which the hydrocyclone or its parts must be replaced. A heavy hydrocyclone requires more stable or stronger foundations. In the case of transport, this results in correspondingly higher transport costs. If the inner layer has been worn down after a long period of operation, the outer steel layer or shell will be very quickly worn away by the components of the suspension to be processed in the hydrocyclone, since steel has a relatively low resistance to wear caused by abrasion.

The object of the invention is to improve a hydrocyclone or hydrocyclone parts according to the preamble of claim 1 in such a way that, on the one hand, the manufacturing costs and the weight are reduced, but, on the other hand, the overall wear resistance is increased.

The solution to this problem is, starting from the generic term of claim 1, initially seen in the features of the characterizing part of claim 1. This significantly reduces the manufacturing costs of the outer layer.

At the same time, their weight is significantly reduced in relation to a hydrocyclone or hydrocyclone parts according to the state of the art with the same external dimensions. If, after a certain period of operation, the inner layer has been worn or eroded by the suspension at this or that point, the outer layer made of relatively hard polyurethane provided according to the invention has a significantly higher wear resistance than steel compared to the suspension. This extends the service life of such a hydrocyclone accordingly. The invention therefore achieves the surprising effect that the last-mentioned improvement in function is achieved together with a reduction in manufacturing costs, whereas functional improvements to an object usually have to be bought at the cost of corresponding manufacturing costs.

A preferred embodiment of the invention is the subject of claim 2. Such a cast bond between the two layers results in an intimate bond between the inner layer and the outer layer, which in the case of the star»d

If · · I

I · · t · t

If* ■ ft «

i is not given by the technology. This results in j|

greater stability of the hydrocyclone, or hydro- j

cyclone part and in cases where part of the inner layer has already been worn away, still sufficient hold of the remaining part of the inner layer on the outer layer.

The features of claim 3 make it possible, after the inner layer has been completely or partially worn, to separate it from the outer layer in a relatively simple manner, e.g. by pushing it open or tapping it with a hammer. A new inner layer manufactured in the factory can then be reinserted into the remaining outer layer.

A preferred combined application of the features of claim 2 on the one hand and the features of claim 3 on the other hand is the content of claim 4, which may optionally be supplemented by claim 5. The solid, stability-increasing cohesion by the cast composite is thus limited to the upper part, which is subject to corresponding stress by the inlet, while the lower area (lower part, or middle part and lower part), which is particularly exposed to wear, enables a worn inner layer to be replaced quickly and easily.

The features of claims 6 and 7 represent preferred hardness specifications of the polyurethanes used for the outer layer and the inner layer.

An embodiment of the invention is shown in the drawing and described below. The drawing shows:

Fig. 1: a longitudinal section through a

Lower part, middle part and upper part of composite hydrocyclone,

Fig. 2: a section along the line II-II in Fig. 1.

The hydrocyclone according to the invention consists in principle of three parts, namely the lower part 1, the ^middle part 2 and the upper part 3. The lower part 1 forms

III···

It· · ·

_M C _

the discharge 4 for the heavy or coarse fraction. The middle part 2 forms the area 5, in which the fine or light fraction of the suspension is separated from the coarse or heavy fraction essentially by the hydrocyclone effect. The upper part 3 contains the suspension

nono {nno7n1 aii-P R 11 r» H rlon ü ^ ¹ &Xgr;&Ggr; ¹ ! ^{&Lgr; 1} J f IQ d &Xgr; ¹ ^ ¹ f S &iacgr;&Ggr;&igr; S &Pgr;t}ZW;

lighter fraction. The above-mentioned functions of a hydrocyclone are well known.

According to the invention, the parts, provided they have a load-bearing function, consist of an outer layer, numbered 7 throughout, made of a relatively hard polyurethane, which can thus take on the load-bearing function, and a softer, very wear-resistant inner layer 8 made of a correspondingly softer polyurethane. In a preferred embodiment of the invention, the shore hardness of the outer layers 7 is in the range of 95 to 105 Shore, while the shore hardness of the inner layers 8 is preferably 75 to 85 Shore A.

The layers 7, 8 are connected to one another and held together at their contact surface 9 !preferably by a cast bond. However, it is also possible to proceed in such a way that after casting one of these two layers, a thin silicone layer 11 is applied to the surface intended to rest against the counter surface of the second layer.

worn, preferably sprayed on. This means that after appropriate wear, the inner layer can easily be separated from the outer layer and replaced by another inner layer. In the present embodiment, it is recommended that the outer and inner layers in the upper part 3 be held firmly together by a cast bond, whereas in the middle part

part 2 and lower part 1 between the outer and inner layers, the aforementioned silicone layer is to be provided, since this is where the greatest wear is to be expected. This silicone layer is only indicated in the drawing by number 11 and the associated dividing line between the inner and outer layers of the hydrocyclone parts 2 and 1.

Mart can either first produce the respective outer layers 7 and then cast the inner layers θ into them, or first cast the inner layer and then, after appropriate tempering of the inner layer, cast the outer layer around it. In the latter case, a polyurethane must be selected for the inner layer that can withstand two heat treatments without loss of wear resistance. A polyether polyurethane with a Shore hardness in the range of 80 Shore A is recommended for this purpose. A polyether polyurethane is recommended for this purpose, such as that manufactured by Dupont and sold by Uniroyal under the designation L A2 .

The invention is explained above using the example of a hydrocyclone that is made up of several parts. As already mentioned at the beginning, the invention also relates to a hydrocyclone designed in this way, i.e. a one-piece hydrocyclone. In the latter case, the above-mentioned cast composite is recommended.

- Expectations -

Claims (7)

. BERNHARD iRtCHTBR: .· . . .·\ \.{ ₈₅ oo mornberq co, den PATENT ATTORNEY"' HigeL Representative at the European Patent Office &eegr; European Patent Attorney 04.OB.1989 R/ge Company AKW Apparate and Process GmbH, Georg Schiffer Str. 70, 8452 Hirschau Protection claim: 1. Hydrocyclone, or hydrocyclone parts, consisting of a hard, load-bearing outer layer and a softer, wear-resistant inner layer made of polyurethane, characterized in that the outer layer (7) consists of a relatively hard polyurethane. 2. Hydrocyclone or hydrocyclone parts according to claim 1, characterized in that the outer layer (7) and the inner layer (β) are in a cast bond with one another at their common transition or contact surfaces (9). 3. Hydrocyclone or hydrocyclone parts according to claim 1, characterized in that a silicone layer (11) is provided between the outer layer (7) and the inner layer (8). 4. Hydrocyclone or hydrocyclone parts according to one of claims 1 to 3, characterized in that in a hydrocyclone composed of several parts in its upper part (3) having the suspension inlet (6) and the overflow (10) between the outer layer (7) and inner layer (β) are bonded together, while in the remaining area of the hydrocyclane, in which the separation of the fractions and the discharge of the heavy or coarse fraction takes place, the silicone layer (11) is provided between the outer layer (7) and the inner layer (B). 5. Hydrocyclone or hydrocyclone parts according to claim 4, characterized in that the remaining area of the hydrocyclone consists of a middle part (2) and a lower part (1). 6. Hydrocyclone or hydrocyclone parts according to one of claims 1 to 5, characterized in that the shore hardness of the outer layer is 95 - 105 Shore A. 7. Hydrocyclone or hydrocyclone parts according to one of claims 1 to 6, characterized in that the Shore hardness of the inner layer is 75 - &THgr;5 Shore A.