DD208827A1 - HIGH-FIXED CUTTING PARTS FOR TREATMENT MACHINES - Google Patents

Abstract

The invention relates to high-strength cutting parts for harvesting machines, especially knife blades, finger plates, Raeumplatten or the like., The wear resistance is increased by Haerten. The invention has for its object to provide for cutting parts, especially those for harvesting machines a heat treatment process that can achieve a high bending strength in granting sufficient Haerte and wear resistance. This object is achieved according to the invention by the fact that the cutting unit parts have a bainitic structure state caused by intermediate level verging.

Description

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Title of the invention

High strength cutterbar parts for harvest recovery mills

Field of application of the invention

The invention relates to hoohfeste cutting workstation for harvesting machines, especially knife blades, Pinger plates, Bäumplatten or the like., The wear resistance is increased by curing.

Characteristic of the known technical solutions

Cuttering platforms of the type mentioned are hardened to reduce the cutting ability and to increase the wear resistance. The hardening takes place in accordance with the heat treatment regulations specified for the "material used.

Knife blades, finger plates and Bäumplatten or the like are cured for many years exclusively in the field of cutting edges or working edges

See: TGL 6005, 1974 - knife blades for pingers and double knife cutters; RGW standard 3093-81,1981 - Knife blades for Schneldwerke; DIN sheet 11300, 1957 - knife blades with smooth and toothed sons; Fachbuoh W. Haufe Verlag CF. Winter ¹ see Verlagshandlung Füssen, 1954, p. 173 - tool steels and their heat treatment.

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These stipulated in the cited references and / or recommended regulations for the Wannbehandlung this cutting parts resulting from many years of experience of the user and manufacturer industry. Deviating from the "hardening sonic" used so far, according to which such cutting unit parts have been hardened consistently, they are based on the knowledge that the so-called zone hardening achieves the best possible hardness and toughness results on these cutting unit parts Cutting zones, hardening cracks or bending bridges occurring due to bending loads are unavoidable The failure of these cutting unit parts caused by bending fractures is in particular also due to the occurrence of hardening distortion.

Another part of the premature becoming unusable is also due to the fact that additional structural stresses are generated by the riveting of the cutting unit parts on carrier body. In the case of zone-hardened cutting parts, a substantial part of these disadvantages can be avoided. However, today's demands on high-performance harvesting machines can no longer be met by the cutting-material parts heat-treated in this way.

As an aggravating circumstance for the maintenance of the cutting ability of such Sohneidwerkteile is added that when picking up the crop foreign body enter the cutting units and affect them by mechanical damage in their work behavior.

One of the frequently occurring damage is due to the fact that the cutting unit parts are bent by received foreign body, with the zuge-

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clinging to defective sons of sons, and thereby breaking ·

One of the main demands that the practice makes on the cutting performance of such cutting unit parts is therefore to provide these cutting unit parts with a relatively high bending stiffness with good cutting ability and wear resistance.

There has been no lack of attempts in practice to overcome this problem by exchanging materials or by using modern heat treatment methods and by using surface-coated cutting parts. However, the efforts made only partially to success and have been able to enforce in practice nioht.

Object of the invention

The object of the invention is to make offspring parts of the type mentioned unbreakable and with a high versohleißwlderstand.

Explanation of the essence of the invention

The invention has for its object to provide a heat treatment process for Sohneidwerkteile, especially those for harvesting machines, which can achieve a high flexural rigidity while ensuring sufficient hardness and wear resistance auoh.

This object is achieved in that the cutting unit parts have a caused by Zwischenstufenvergütung balnltlschen structural state ·

It has been found, surprisingly, that the material structure bainite formed as a result of an intermediate-stage coating satisfies the sub-standard requirements for such soffit parts in the fawo world

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Unacceptable extent is sufficient to ensure both good coffin ability and high flexural rigidity »

Thus, for example, in the case of double-stage-tempered knife blades with the same hardness, the bending stiffness is approximately 2.5 times the previously zone-hardened design, whereby the risk of bending bending has been substantially reduced with the same wear resistance.

The occurrence of workpiece distortion due to the hartetechnischen heat treatment and the emergence γόη hardening is almost completely avoided by the Zwischenstufenvergütung · It is obvious that in the reached by intermediate stage bending stiffness of such cutting parts of duroh bending break or similar phenomena caused failure of the reapers on harvesting machines in substantial extent, which has an advantageous effect on the productivity of such machines. The application of Zwssohenstufenvergütung in such cutting parts also allows to carry out the heat treatment process with simpler teohnisohen means and is also technologically easier to control ·

embodiment

The invention will be explained in more detail below using an exemplary embodiment, the intermediate stage tempering of knife blades made of the steel material CK 67.

The knife blades are austeniZed in a single pass of the belt at a throughput time of 10 minutes and at a temperature of 830 ° C. In a hot bath, the austenitizing knife blades are quenched to a temperature of 260 ° C to 270 ° C, with the indwelling tent in the bathroom about 30 minutes.

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For the steel material CK 67, the material structure Banit is formed under these conditions. By means of a discharge system installed in the hot bath, the knife blades are transported in a water bath with a temperature of 80 ° G, from where they are transported by a second discharge system to a grate. Here, the water adhering to the knife blades drops or evaporates due to the temperature of 80 ° C.

Knife blades, fagerplatten, Bäumplatten or the like. Can also be made of other suitable for the intermediate stage steel materials. The austenitizing temperatures required for these steel materials and the temperatures required for bainite formation can be found in the corresponding ZTU diagrams.

Claims (1)

invention claim High-strength cutting unit parts for harvesting machines, in particular knife blades, finger plates, clearing plates or the like, whose wear resistance is increased by hardening, characterized in that the cutting unit parts have a bainitic microstructure state caused by interstage tempering.