DE202008014887U1 - Stirrer for hot melts - Google Patents

Abstract

Stirrer with agitator (4), pivot bearing (5) and rod with stirring head (6), wherein the rod with stirring head (6) to be touched in the Melt (2) immersed, all around insulation (7) has, so that the heat conduction is interrupted from the melt to the rod (6).

Description

The Invention relates to a stirrer for hot melts, in particular melts of low-melting metals or metal alloys.

Known are stirrers for such Melting from a mixer, a long rod that dips into the melt and one below Stirring head attached to the rod, for example, has an impeller made of steel. Through the staff, depending on oxygen resistance the one to be touched Melt, another inert gas introduced into the melt. When stirring turns the rod with the stirring head, so the pivot bearings for the stirring motion at the top of the joint between the mixing arm and rod are arranged. These pivot bearings are very stressed, there enormous forces while stirring these melts are spent. To the mechanical load is still the thermal load, as the pivot bearing on the heat conduction directly with the heat from the melt, which can reach up to 800 ° C can be charged.

To The prior art, these pivot bearings must be changed often because no material can withstand these loads for a long time.

task Therefore, it is the object of the present invention to provide a stirrer for up to 800 ° C hot melts specify a lower load materials of the stirrer, in particular also the pivot bearing between the mixing arm and rod with stirring head.

Of the The invention and the solution of the problem are in the claims, the description and the figure disclosed.

Accordingly the subject of the invention is a stirrer with a stirring arm, pivot bearing and rod with a stirring head, the rod with stirring head, the one to be touched Melt immersed, all around has insulation, so that the heat conduction is interrupted from the melt to the rod.

To the one becomes thereby the material of the stick and the entire stirrer, thus especially the pivot bearing, spared and the other goes the Melt through the rod no heat lost.

To a preferred embodiment of The invention is the insulation, for example, a cylinder, the Bar completely encloses. This is a round embodiment The invention, which may just as well have a square shape.

To a further embodiment is the insulation of the same material as the boiler or the basin in which the melt of the low-melting metals / metal touched becomes.

When For example, low melting metal becomes a metal here such as lead, tin, magnesium, sodium, or even low-melting Alloys called solders. These metals or metal alloys melt in a temperature range up to 800 ° C, which for metals, the melting points up to to 3400 ° C can have (compare the high-melting metal tungsten) as low-melting becomes.

To a preferred embodiment For example, the insulation is made of steel or something called heat-resistant steel, which are particularly heat-stable steels.

To a preferred embodiment of The invention is, for example, a heat-insulating in the insulation Material, such as a mineral wool introduced.

To a preferred embodiment is the insulation up to the stirring head provided along the entire rod along.

To another embodiment the insulation is only on one or more parts of the Staff provided.

To another embodiment the insulation is solvable attached to the rod.

To an embodiment the insulation is fixed to the rod.

To an embodiment The insulation is designed to be opened and closed can, for example, the heat-insulating fabric in the insulation can be easily replaced.

To an embodiment the invention, the insulation is designed so that they later on Rod can be attached, so it can be retrofitted at the stirrer.

To a further embodiment the invention are at least two basically parallel tubes in the rod Initiation of inert gas provided so that, for example, a pipe is provided as a replacement tube.

The For example, pipe for introducing inert gas is also made of steel or heat-resistant steel.

The impeller on the rod is, for example, also made of steel or of a refractory and inert, that is to say, reaction-resistant metal, such as For example, bismuth or tungsten.

in the Below, the invention will be described with reference to a figure which is an exemplary embodiment The invention shows, closer explained.

The figure shows a pelvis 1 with up to 800 ° C hot melt 2 For example, a raw magnesium melt in which magnesium is separated from impurities. The melt is stirred by a stirrer. This stirrer has a motor 3 , a mixer 4 a pivot bearing 5 a rod with a stirring head 6 and this has according to the invention an insulation 7 which, for example, covers the entire bar and protects it from the heat from the melt, without however impairing it by material and / or temperature.

The motor 3 , the mixing arm 4 and the pivot bearing 5 are according to the invention, the commercial and thus compliant with the prior art and are therefore not further described here.

According to the invention, improvements are made to the rod with stirring head 6 made, in particular, this is one, for example cylindrical, insulation 7 provided so that the heat from the melt does not affect the parts of the stirrer, especially the pivot bearings 5 unnecessarily straining.

The insulation 7 for example, the rod is in two parts, it comprises a housing and a filling. For example, the housing is made of the same material as the pelvis 1 for the molten metal, because it should any chemical or magnetic reactions that are traceable to different normal potentials of the metallic materials involved, as possible avoided. In particular, the housing for insulation 7 be made of a steel, for example, a particularly heat-resistant steel or a so-called heat-resistant steel. But it is also conceivable that the housing is made of a ceramic material or a temperature-resistant fiber.

at the two-part embodiment described here by way of example The invention is the filling for example, mineral wool or other heat insulating Material mixture.

As well Well, the insulation can be made of a glass or a ceramic and made in one piece.

One piece is called here only that the insulation itself does not comprise a housing and a filling, but rather that she only has one kind of material. The one-piece insulation, as well as the two-piece be constructed so that it can be opened, for example, around the filling replace or afterwards the insulation to a according to the state the technology constructed stirrer Roast with uninsulated stick.

Of the mixer head is according to the invention again uncritical and corresponds to the state of the art and will Therefore, not described here. For example, can it is a so-called impeller, so one with Slotted disk through which the melt by a rotary motion passed becomes.

In the bar 6 For example, a tube for supplying the melt with inert gas is provided, which is important, for example, in the case of oxidation-sensitive melts, such as a magnesium melt, so that the stirring process can be carried out. In order for the stirring to proceed as evenly as possible, it is even possible for a parallel-guided empty tube to be provided in the rod, through which inert gas such as argon can likewise be introduced into the melt or simply held there as a replacement tube.

By the invention becomes possible for the first time a stirrer for one To provide low-melting molten metal, in which by a appropriate insulation the heat from the molten metal as possible little is forwarded to the loaded parts of the stirrer. By the invention can completely different lifetimes of the bearings and replacement cycles of the loaded ones Parts of such a stirrer be achieved.

Claims (13)

Stirrer with mixing arm ( 4 ), Pivot bearing ( 5 ) and rod with stirring head ( 6 ), wherein the rod with stirring head ( 6 ), which in the melt to be stirred ( 2 ), all around insulation ( 7 ), so that the heat conduction from the melt to the rod ( 6 ) is interrupted. Stirrer according to Claim 1, in which the insulation ( 7 ) is round. Stirrer according to claim 2, wherein the insulation ( 7 ) is a cylinder that holds the rod ( 5 ) completely encloses. Stirrer according to one of claims 1 or 2, wherein the insulation ( 7 ) and the pelvis ( 1 ) are made of the same material. Stirrer according to one of the preceding claims, wherein the insulation ( 7 ) is made of steel or a heat-resistant steel. Stirrer according to one of the preceding claims, wherein the insulation ( 7 ) is angular. Stirrer according to one of the preceding claims, wherein the insulation ( 7 ) comprises a housing and a filling. Stirrer according to one of the preceding claims, wherein the insulation ( 7 ) comprises a filling of a heat-insulating material. Stirrer according to one of the preceding claims, wherein the rod ( 6 ) comprises a tube for introducing inert gas into the melt. Stirrer according to one of the preceding claims, wherein in the rod ( 6 ) is still provided a parallel tube. Stirrer according to one of the preceding claims, wherein the insulation ( 7 ) is open. Stirrer according to one of the preceding claims, wherein the insulation ( 7 ) only in parts or a part of the rod ( 6 ) is provided. Stirrer according to one of the preceding claims, wherein the insulation ( 7 ) along the whole rod ( 6 ) is provided.