JPH0238692B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotating drum of an open-end spinning machine made of temperable steel and in which at least the inner part of the rotating drum in contact with the rovings is protected from wear, and to a method for producing the same.

In open-end spinning machines, the rotating drum experiences significant wear where it comes into contact with the fibers or yarn being produced. This is disadvantageous because the shape and surface structure of the rotating drum greatly influences the structure and spinning stability of the spun yarn.

Conventionally in known open-end spinning machines, significant changes in surface structure and surface properties occur on the inside of the rotating drum at the point of contact with the fibers or rovings, due to wear of the rotating drum during the spinning operation. This has had adverse consequences for the yarn properties and the stability of the spinning process.

This results in a requirement for wear-resistant surfaces. On the other hand, it is advantageous to increase the economy of the open-end spinning frame by increasing the rotational speed of the rotating drum. These two requirements are such that wear-resistant materials are generally brittle and have too high tensile strength.
However, the high rotational speed of the rotating drum is contradictory in that it requires materials with high yield points, tensile strength, and toughness.

In West German Patent Publication No. 2909739,
It has already been proposed that the rotating drum is made of temperable steel and that at least the inner part of the rotating drum that is in contact with the roving has a surface layer consisting of one or more metal oxides or metal carbides, alone or in combination. has been done. In any case, such rotating drums may not be corrosion resistant.

The object of the invention is to produce yarns of uniform properties even with increased operating times and to maintain the stability of the spinning process, but at the same time with a high rotational speed of the rotating drum and with low material and energy expenditure. This enables increased productivity of the spinning machine.

According to the invention, this object is achieved by providing at least the inner part of the rotary drum of temperable steel in contact with the roving with a highly wear-resistant surface layer containing iron boride, which layer is covered with a protective gas. This problem is solved by providing at least one surface protective layer formed below and containing at least one corrosion-resistant metal on the surface layer.

The advantage of the invention is that particularly good, uniform spinning results are obtained over a long period of time, with the speed of rotation of the rotating drum being increased and thus the production. By means of effective corrosion protection, the good properties of the rotating drum with regard to anti-wear measures are maintained.

Such a rotating drum combines the properties of a wear-resistant, hard, but relatively brittle surface with favorable material properties with respect to stresses at high rotational speeds.

The present invention provides a method for producing a rotating drum made of such temperable steel, which method comprises boronizing at least the inner part of the rotating drum in contact with the roving under a protective gas and "tempering" the rotating drum. It consists of carrying out a heat treatment known as , which increases the toughness of the material with a high yield point, and applying a surface protective layer containing at least one corrosion-resistant metal.

Next, the present invention will be explained in detail with examples based on the accompanying drawings.

The rotating drum 1 shown in the drawings is prefabricated from temperable steel. In final assembly, the rotating drum is fitted with a steel shaft 2. After the rotating drum is preliminarily manufactured using a rotating machine, the hole into which the shaft 2 is inserted is temporarily closed with a heat-resistant material. The entire internal space 3 is then filled with boron-containing powder. Opening drum 1 with upward opening
to a temperature of 920°C in a retort under protective gas.
After cooling, excess unused boron-containing powder is removed from the interior space 3. The rotary drum 1 is then heated again under protective gas in the retort to 830 DEG C. and immediately subsequently quenched in oil. The rotary drum 1 is then tempered in a neutral salt bath at a temperature of 400 DEG C. and quenched again in oil. Subsequently, the rotating drum 1 is galvanized. This galvanizing is followed by a chromate treatment to impart corrosion resistance to the wear-resistant surface. In this case, for example, the rotating drum is immersed in a dichromate solution and subsequently washed in water.

The rotating drum 1 manufactured in this way was provided with a shaft 2, and the rotation speed was set to 200,000 rpm. No changes were observed in the rotating drum during and after the trial run.
The rotating drum subsequently gave the expected good spinning results in the spinning tests.

The boron-containing agent may be a boron-containing paste, a boron-containing liquid, or a boron-containing gas. The paste or liquid is applied by painting, dipping or spraying. The rotating drum must then first be dried once before further processing.

The finishing rotary drum 1 has a highly wear-resistant surface layer 4 of iron boride, provided with a surface protective layer of zinc, which not only protects the rotary drum from corrosion, but also protects it from corrosion. It is also a factor that further improves the spinning results.

Instead of a zinc layer, a nickel layer can also be applied as a surface protection. For this purpose, a rotating drum is immersed in a bath in which nickel is present in dissolved form. During the chemical treatment, nickel is deposited on the surface of the rotating drum.

[Brief explanation of drawings]

The accompanying drawings show an embodiment of a rotating drum according to the present invention. 1... Rotating drum, 4... Surface layer.

Claims (1)

[Scope of Claims] 1. A rotating drum of an open-end spinning frame made of temperable steel and in which at least the inner part of the rotating drum in contact with the rovings is protected from wear; The contacting inner part has a highly wear-resistant surface layer 4 containing iron boride.
A rotating drum for an open-end spinning machine, characterized in that the surface layer 4 is provided with at least one surface protective layer containing at least one corrosion-resistant metal. 2. The rotating drum according to claim 1, wherein the surface protective layer is an electrolytically applied and chromate-treated zinc layer. 3. The rotating drum according to claim 1, wherein the surface protective layer is a chemically applied nickel layer. 4. A rotating drum in which the rotating drum is made of temperable steel, at least the inner part of the rotating drum that comes into contact with the rovings is protected from abrasion, said inner part having a high abrasion resistance and containing iron boride. A method for manufacturing a rotating drum of an open-end spinning machine, comprising a surface layer of at least one roving of the rotating drum, and provided with at least one surface protective layer containing at least one corrosion-resistant metal on the surface layer. The inner part in contact with the material is brought into contact with a boron-containing agent and boronized by thermal action under a protective gas, during which time the rotating drum is subjected to a heat treatment known as tempering to increase the toughness of the material with a high yield point. , and subsequently applying a surface protective layer containing at least one corrosion-resistant metal. 5. The method according to claim 4, wherein the surface protective layer is applied as a zinc layer by electrolysis in an immersion bath, and the zinc layer is treated with a chromate. 6. The method of claim 4, wherein the surface protective layer is a nickel layer deposited by chemical methods in an immersion bath.