Machining of kitchenware parts

FIELD: process engineering.

SUBSTANCE: invention relates to machining of parts from ferrous alloys containing at least 80 wt % of iron or from unalloyed steel for kitchenware for antiscore properties. Nitration or carbonitriding at 592-750°C are conducted to facilitate the creation of nitrous austenite ply between nitride and diffusion plies, oxidation is made to facilitate the conversion of at least a portion of nitride austenite into the phase of higher hardness. The latter is nitride braunite or nitride martensite. Note here that higher hardness is a mid magnitude between nitride ply hardness and that of diffusion ply.

EFFECT: higher burnt-on, anti-abrasion and corrosion resistance properties, lower production costs.

18 cl, 3 dwg

 

The invention relates to a method for machining parts for kitchen utensils made of ferrous alloys, non-stick, carpinetti and corrosion resistant, as well as to the parts treated in this way.

There are different materials or combinations of materials used for the manufacture of kitchen utensils: steel (alloy or non-alloy), aluminum, stainless steel (i.e. containing, as a rule, more than 11% chromium, copper or alloys of silver, in particular, coated or uncoated their surface polymer layers on the basis of polytetrafluoroethylene (PTFE, marketed in particular under the trademark Teflon). Each of these materials has its own advantages and disadvantages in the case of the use of this function.

Aluminum has excellent corrosion resistance, providing the ability to safely wash kitchen utensils, including dishes with the use of detergents, but at the same time, it is easy to scratch, and its non-stick properties is negligible. For this reason it is often used in combination with type coating is polytetrafluoroethylene.

Austenitic stainless steel containing about 18% chromium and 10% Nickel) also has high corrosion resistance and has a greater than aluminum, resistant to scratches. At the same time,it has low thermal conductivity, that is not conducive to uniform the temperature distribution of kitchen utensils, such as pots, pans, panels for frying, roaster, irons, griddles, saucepans, grille (grill), the form for the oven or pan.

Copper is a very good conductor of heat, suitable recognized for thermal cooking food of high quality. At the same time, this material is expensive and is used exclusively for cooking utensils of the highest price category.

Steel, not related to stainless, have a significant advantage over the above-mentioned materials lies in their price. In fact, steel, especially non-alloy steel (non-additive) or low (i.e. in which the content of all elements of additives does not exceed 5% by weight), are easily and widely available, their price is low and varies little with respect to the price of stainless steel or copper. This is why steel is not related to stainless steel is widely used as a basic material of kitchen utensils lower price category.

At the same time, these steels have very low resistance to corrosion, especially in the case of cleaning utensils alkaline detergents (prescribed for cleaning in the dishwasher), the surface is easily scratched, and their non-stick properties are low.

From the Pat is the US 2008/0118763 A1 should what cooking utensils may be the ferritic AttorneyGeneral at a temperature of 1060°F (571°C) for 3 hours in an atmosphere of 55% nitrogen, 41% of ammonia and 4% CO2. Thereafter the gas oxidation (post-oxidation) at a temperature less than 800°F (about 427°C) and the application of temporary protection exposure at 500°F (260°C) for 45 minutes using cooking oil. According to this document the treated surfaces have a high hardness and superior resistance to corrosion.

Treatment nitriding, azotonaweglanie, oxyacetylene and oxazolidinones (prefix hydroxy - means that after nitriding or azotonaweglanie is the stage of oxidation) are used in mechanical engineering (automotive industry: valve, gas shock absorbers, ball joints; construction machines: swivel, hydraulic jacks and the like).

These treatments carry out industrially or gas method (in an atmosphere of ammonia-based), or a plasma method (fluorescent discharge under low pressure)or liquid method (ionic liquid environment, see, for example, document US 2003084963).

Processing industry nitriding azotonaweglanie, oxyacetylene and oxazolidinones are usually performed in the ferritic phase (on dia is using iron-nitrogen), that is, at temperatures below 592°C.

This forms a layer of iron nitride, and the bottom layer qualifies as a diffusion layer.

Above 592°C, the formation of phase γN (nitrogen austenite, usually denoted γN) between the nitride layer and the diffusion layer. Nitrogen austenite is a special steel microstructure. The exact temperature, above which there is a formation phase γN, depends on the specific composition of the steel. If it contains a lot of alloying elements, then this limit temperature may be increased up to 600°C.

The layer of nitrogen austenite is converted to nitrogen Brunet, another special steel microstructure under the influence of temperature during phase oxidation, which is usually carried out after the step of nitriding or azotonaweglanie. With regard to the field of mechanical parts, the phase oxidation is usually carried out in connection with the fact that it is desirable to make the parts resistant to corrosion, so that the nitriding improves wear resistance and oxidation - corrosion resistance.

This retransformation in brownit is generally undesirable, since the applications in the production of mechanical parts for which azotonaweglanie actually is, the presence of a layer of nitrogen braunite PR which gives fragility in shock.

In fact, a typical mechanical loads, which tend to limit by azotonaweglanie are cyclic and/or variable loads that are played with a large number of cycles, such as, for example, surface fatigue or shock.

Thus, the presence of a layer of braunite usually try to avoid, as the fragility of this layer can lead to flaking or cracking of the nitride layer under the action of impact (significant, short and localized energy transfer between the two parts upon movement of one relative to another). Therefore, operation azotonaweglanie and nitriding are usually performed in the ferritic phase. In the case of austenitic nitriding already posted, the post-oxidation is conducted usually at a temperature less than 200°C, to avoid retransformation nitrogen austenite in braunite (see, for example, patent EP 1180552).

At the same time, referring to the ideas of the patent US 2008/0118763 A1, the applicant has found that in the post-oxidation performed directly after azotonaweglanie used elevated temperatures (above 200°C) is called a vacation at the level of the zone of diffusion. The consequence of this vacation is to drop the hardness of the diffusion zone, which affects the resistance to abrasion processed kitchen approved the ri.

Therefore, in the case when the applied load, which acts on the material throughout the mass, not only on a solid layer of its surface, the substrate is deformed, and the surface hard layer crack and peel.

The same thing happens at the stage of "roasting" agent temporary protection, which is carried out between 150 and 260°C, as well as throughout the life of the utensil, in any scenario, kitchen utensils at a temperature exceeding 200°C.

This, in particular, is contraindicated in the case of low-carbon steel, which usually used for kitchen utensils.

At the same time, it should be noted that the methods azotonaweglanie require significant energy expenditure and what is interesting to monitor the processing time in order to limit the final cost. One of the drawbacks of the processing mode, presented in document US 2008/0118763 A1 is its duration, which is very long (3 hours).

In this context, the problem offers to resolve the invention is to make the surface of the kitchen utensils of steel (unalloyed or nizkolegirovannoj) improved antiprivacy, carpinetti properties and corrosion resistance at low cost of production.

To solve this problem, a method of processing items for cooking the creature, characterized in that it comprises in series:

- stage nitriding between 592 and 750°C in order to accelerate the creation of a layer of nitrogen austenite;

- processing stage that is designed to facilitate the conversion of at least part of the nitrogen austenite phase increased hardness.

The method is notable in that it allows you to protect parts for kitchen utensils from scratch.

Initial hardening of parts (stage nitriding) can be implemented either by austenitic nitriding, or for the account of austenite azotonaweglanie. It should be clarified that under azotonaweglanie refers to the processing of diffusion of nitrogen and carbon, which is considered as a particular case of nitriding, and the term "nitride" refers to processing in a broader sense, meaning at least the diffusion of nitrogen. Created a layer of austenite is located under the nitride layer over the diffusion layer.

Subsequent processing stage, which can be, in particular, heat treatment or thermochemical treatment, can improve the hardness of nitrogen austenite, thereby changing its nature. The hardness is measured according to standard protocols. As an example, it may preferably be increased by at least 200 HV0,05or prob is tenderly 300 HV 0,05.

According to the first variant implementation phase increased hardness is Brunet. The conversion can be carried out, in particular, by switching to a temperature above 200°C in a period of time longer than 10 minutes. In the example related to this implementation variant, the hardness changing its nature phase increases from about 400 HV0,05to about 800 HV0,05.

The processing stage is adapted to allow the conversion layer of nitrogen austenite in nitrogen Brunet. To this end, in particular, it is carried out with a low content of active nitrogen around the details. Under the active nitrogen understand, depending on the method applied nitriding, ammonia gas, ionized nitrogen or nitrogen-containing molten salt.

A simple way of implementing transformation stage is to eliminate any presence of active nitrogen in the environment in which you have placed the items, however, can be limited by decreasing the concentrations of these active particles sufficient to terminate the reaction nitriding. The conversion is carried out at a temperature less than or equal to the temperature of nitriding, for example at a temperature of less 480°C.

It should be clarified that in between stage of nitriding and stage conversion parts can be moved or can the OS is be passed on the same place.

In addition, the conversion step may be carried out directly after step nitriding, and without the need to cool the parts, which allows to obtain a favorable kinetics, but it can also be carried out and after some time, during which the details will be cool to ambient temperature.

According to the second variant implementation phase increased hardness represents a nitrogen martensite, and the conversion may, in particular, to be made by switching to a temperature below -40°C in a period of time exceeding 5 minutes. Nitrogen martensite is a special steel microstructure that is different from the nitrogen austenite and braunite. In the example related to this implementation variant, the hardness of the phases, changing its nature varies, therefore, from about 400 HV0,05to about 750 HV0,05.

When applied to kitchen utensils the applicant has established that obtained in this way a layer package material has a high resistance to scratches caused by sharp objects (forks, knives), than the packet received by ferritic nitriding. It seems that the layer braunite or martensite formed during the transformation stage, serves as a support located above the layer of nitride.

In fact, it turns out that mechanically the loads on a typical working surfaces of kitchen utensils (mixing, cutting food) contact area of kitchen utensils with sharp objects is very small.

When nitriding or ferritic azotonaweglanie the applicant has established, as described above, the nitride layer locally deforms as the diffusion layer does not have sufficient hardness (200-250 HV0,05for non-alloy low carbon steels), in order to support him. Is localized deformation part and a layer of nitride, which crack and peel.

Without going into any special explanation, we can assume that when austenitic azotonaweglanie layer of nitrogen austenite, retransforming in brownit or martensite, provides mechanical support layer of nitride, which is more effective compared to one that is able to provide only one diffusion layer in the parts that have not undergone processing according to the invention. The nitride layer no longer deformed under the action of a typical kitchen utensils mechanical stresses, which prevents scratching.

The same thing happens with corrosion resistance. Inherently layers of nitride and oxide are passive layers, that is, they do not corrode. However, the corrosion oxidatively or oxazolepropionic parts may occur due to the fact that the layers is of Frida and oxide is never completely free from defects. Therefore, the electrolyte may come into contact with the substrate, which, in the end, still corrode.

Limit the risks of scratches on the layers of nitride and oxide due to processing according to the invention protects against corrosion kitchen utensils, processed according to the invention.

Note also that the observed effect is associated with the use of kitchen utensils, in which the frequency of the loads on the surface is low (only a few hits from time to time with a knife or spatula) and, usually, not always in the same place (it is rare that a dozen or a hundred blows with a knife had exactly the same place on the pan). Therefore, the method is used mainly to such kitchen utensils like pots, pans, panels for frying, roaster, irons, griddles, saucepans, grille (grill), the form for the oven or pan, and, in particular, to their surfaces intended to come into contact with food during the heat of cooking. Kitchen utensils adapted for use in heat cooking at home, a group of people, restaurants or industrial kitchens for cooking ready meals designed, for example, for packaging and sale.

It appears that the best character n the availability of layer braunite or martensite due to the fact, he avoids too high gradients of hardness (as it takes place between the nitride layer and the zone of diffusion in the classical nitriding steels type XC10-XC20).

Layer braunite or martensite, which has an intermediate hardness between the hardness of the nitride layer and the hardness of the diffusion zone, reduces, apparently, the hardness gradient in such a way that provides a higher mechanical resistance. The latter is especially advantageous, since, as mentioned above, the phase oxidation leads to the reduction of hardness in the zone of diffusion.

At the same time, using temperature processing components between 595 and 700°C may be increased two or three times the kinetics of diffusion in comparison with the processing performed between 530 and 590°C, which allows to reduce processing costs and to reduce energy costs required for its implementation.

In some preferential embodiments of the processing stage, designed to facilitate the conversion in braunite, is also a part of the controlled oxidation, which also allows you to get the enhanced effect of protection against corrosion.

An alternative, or a combined image, conversion to brownit includes hot drying at temperatures above 250°C over time, amounting to between 20 minutes and 3 hours, etc is what this hot drying followed by oxidation or precedes the oxidation in boiling brine between 120 and 160°C. The brine can have, in particular, the temperature between 130 and 145°C.

According to one procedure, the method comprising the conversion Brunet or martensite, additionally includes an oxidizing gas method between 350 and 550°C.

An alternative, or a combined image, it includes oxidation in a bath of molten salts between 350 and 500°C.

An alternative, or a combined image, it includes oxidation in boiling brine between 120 and 160°C, or between 130 and 145°C.

Preferably, the nitriding includes a phase azotonaweglanie. It can also include a single phase nitration, followed or preceded by a phase azotonaweglanie. Thus, the phase azotonaweglanie can be supplemented by optional phase diffusion of nitrogen without the carbon diffusion.

Azotonaweglanie advantageous because it allows to obtain a monophasic nitride layers, which improves the mechanical resistance of the parts to shocks or scratches, for example, over that which is obtained when the invention is implemented with a nitriding without azotonaweglanie.

According to one implementation variant, the nitriding includes nitriding in the gas phase, including the optional azotonaweglanie in the gas phase. According to other variant Rea is Itachi it includes a plasma nitriding method, including the optional azotonaweglanie plasma method.

According to the third variant of implementation it includes nitriding in ionic liquid environment, including the optional azotonaweglanie in ionic liquid medium.

According to an advantageous characteristic, the nitriding is carried out for a time amounting to between 10 minutes and 3 hours, and preferably between 10 minutes and 1 hour.

It can be preferably carried out at a temperature of between 610 and 650°C.

The method mainly complemented by a preliminary degreasing of parts.

The method further includes mainly the pre-heating of the workpiece between 200 and 450°C in the furnace during the time average of between 15 and 45 minutes, after degreasing and before nitriding, in order to prepare the items to the nitriding. This allows you to gain time in the application of the method, in particular, in view of the fact that the details are not cooled reaction medium, when they enter into it.

According to another advantageous characteristic of the items get temporary oily protection at the end of processing to further enhance their corrosion resistance in excess of the effect of protection already received treatment according to the invention, but without this additional protection.

Finally, the method is advantageous because it is additionally what makes processed detail the properties of wear resistance and resistance properties fouling.

Check also that the method, in particular, is applicable to parts made of ferrous alloys containing at least 80% of iron by weight, and even parts of unalloyed or low-alloy steel.

The invention also offers cookware, processed by the method according to the invention.

The invention will be described in detail in connection with the enclosed figures, in which:

- Fig. 1 shows the hardness profile measured on the subject of kitchen utensils, like processed by the method according to the prior art,

- Fig. 2 shows the hardness profile measured on the subject of kitchen utensils, processed according to the preferred implementation variant of the invention,

- Fig. 3 shows the superimposed on each of the two previous profiles.

The entire route processing can be divided into several stages: first of all, carry out the degreasing of parts to remove all traces of organic compounds on the surface, which can prevent diffusion of nitrogen and/or carbon.

Then the part is heated to a temperature austenitic nitriding or azotonaweglanie (between 592 and 750°C), and preferably to a temperature comprising between 610 and 650°C. the nitriding Treatment or azotonaweglanie continues over time, constituting between 10 minutes and 3 hours, and preferably about the 10 minutes to 1 hour.

At the third stage details occiderit at a temperature of between 350 and 550°C, and preferably from 410 to 440°C.

An alternative may be oxidation in boiling brine at a temperature of between 120 and 160°C, and preferably between 130 and 145°C.

In this case, the required hot items are to be dried at a temperature exceeding 250°C, in a period of time amounting to between 20 minutes and 3 hours, and preferably 1 hour to convert the layer γN in Brunet.

Finally, the details get temporary protection in the form of edible oils to improve their corrosion resistance in excess of the effect of protection already received treatment according to the invention, but without this additional protection.

The tests helped to identify the important advantages resulting from such processing path, as proposed by the invention. Austenitic azotonaweglanie performed at 640°C for 45 minutes in ionic liquid medium, containing by weight 15% tiantou, 1% cyanide and 40% carbonates.

The parts were then immersed directly in the bath oxidation at 430°C for 15 minutes. Then the parts were cooled in water, rinsed and dried. At the end of their surface inflicted edible oil (sunflower oil) to increase the corrosion resistance.

The morphology of the oxide layer acts as a sponge for film of oil, which astae is camping in the micropores of the layer. Despite the lack of need to perform the final stage of the "roasting" of the latter may still be implemented to facilitate retention of oil by the oxide layer.

The consequence of this processing is a significant increase in the hardness of the layer, which serves as a support layer of nitride, compared with the process according to the prior art.

The figure 1 presents the profile of hardness (measured in accordance with standard Protocol Vickers) for details (steel XC10), processed according to the prior art (ferritic azotonaweglanie and oxidation). Hardness is measured on the cross section. The nitride layer 100 has a hardness of about 1000 HV0,05while diffusion layer 110 has a hardness of 180 HV0,05. The transition between the hardness of these two layers is sharp, in less than 3 microns, in the vicinity of a depth of 20 microns.

The figure 2 shows the hardness profile for identical items, processed according to the described embodiment of the invention. Hardness was also measured in the transverse slice. The hardness of the nitride layer is about 1000 HV0,05while the hardness of the diffusion layer is of the order of 180 HV0,05. Distinct two transitions on the hardness profile: one of 20 microns and the other at 28 microns. The hardness of the intermediate layer, qualified as a layer of nitrogen is about braunite, is about 820 HV0,05. The overall gradient is smaller than in figure 1.

Figure 3 provides a comparison of hardness profiles observed after treatment according to the invention and after the processing of ferritic azotonaweglanie and oxidation.

The hardness of the intermediate layer 205 occupies an intermediate position between the hardness of the diffusion layer 210 and the hardness of the nitride layer 200.

At the same time, implemented thus the route of temperature treatment lasts only one hour, which well demonstrates the effectiveness of the invention in the energy plan.

The resulting kitchen utensils acquire enhanced non-stick properties, as evidenced by the ability to clean burnt food after drinking.

Check now existing alternative treatment options. Processing azotonaweglanie can be performed in the gas phase with atmospheres on the basis of ammonia (NH3), nitrogen (N2and one or more combustible gases, such as methane, ethane, propane, butane, pentane, acetylene, carbon monoxide, carbon dioxide, endothermic gas, exothermic gas.

Processing azotonaweglanie can also be performed by a plasma method: in a cavity with low pressure (typically 5-7 mbar) details are polarized under high eg is feared. This creates a luminescent discharge, and the gas mixture (typically 79.5% of N2+20% H2+0.5% of CH4) dissociates, allowing the active nitrogen and carbon to diffuse.

Processing azotonaweglanie can also be performed by liquid method (ionic liquid media), as already mentioned, in the bath of molten carbonates, tiantou and cyanide. The cyanate ions (CNO-) serve as a source of nitrogen, while traces of cyanide (CN-) serve as a carbon source.

Stage oxidation must be controlled and can run gas method with an oxidizing atmospheres such as air, controlled mixture of N2/O2, water vapor, nitrous oxide, etc. in any case, the purpose is the formation at temperatures comprising between 350 and 550°C, a layer of iron oxide Fe3O4black color, which is a passive oxide, which after its formation prevents the formation of rust (iron oxide Fe2O3the red color).

Oxidation may also be carried out in ionic liquid media at temperatures comprising between 380 and 470°C, during the time from 5 to 40 minutes.

And, finally, the oxidation can be performed in brine (a mixture of water, nitrate, hydroxide) at a temperature of between 100 and 160°C, during the time from 5 to 40 minutes./p>

In this case, the required post-vacation at a temperature exceeding 250°C, for retransformation layer γN in Brunet.

In accordance with the second variant of realization of nitrogen austenite retransformed in nitrogen martensite in the cryogenic processing between -40 and 200°C in a period of time amounting to between 5 minutes and 3 hours, and preferably between 1 hour and 2 hours.

Nitrogen martensite is a structure, the hardness of which is close to the hardness of nitrogen braunite. The applicant has found that this provides the effect of a mechanical support layer of iron nitride.

In accordance with this implementation option route processing is as follows:

- degreasing to remove any traces of organic product

- pre-heating at a temperature between 250 and 400°C,

- austenitic azotonaweglanie between 592 and 650°C,

- cooling to ambient temperature,

- cryogenic treatment at a temperature of between -40 and 200°C,

- oxidation either in the gas atmosphere, or in a salt bath or in boiling brine.

In this implementation, the applicant has found that the preferred oxidation in boiling brine, as it allows to obtain a hardness of nitrogen martensite in excess of 100 numbers hardness Vickers hardness obtained by oxider the processes at high temperatures (over 300°C, in particular, in the gas atmosphere).

The invention is not limited to the described variants of implementation, but on the contrary covers all variants of implementation at the disposal of specialists in this field of technology.

1. Method of machining parts for kitchen utensils to protect these parts from scratch, and these parts are made of ferrous alloys containing at least 80% of iron by weight, or from non-alloy steel, characterized in that it includes sequentially the first stage of nitriding or azotonaweglanie between 592 and 750°C in order to accelerate the creation of a layer of nitrogen austenite between the nitride layer and the diffusion layer, the step of processing with oxidation, designed to facilitate the conversion of at least part of the nitrogen austenite phase high hardness, and this phase is nitrogen Brunet or nitrogen martensite, and this the increased hardness is intermediate between the hardness of the nitride layer and the hardness of the diffusion layer.

2. The method according to claim 1, characterized in that the phase of increased hardness is nitrogen Brunet, and the conversion carried out above 200°C in a period of time longer than 10 minutes.

3. The method according to claim 1, characterized in that the phase of increased hardness is nitrogen martensite, and the conversion of the OS is p below -40°C for time exceeding 5 minutes.

4. The method according to any one of claims 1 to 3, characterized in that the processing step includes oxidation in a bath of molten salts between 350 and 500°C.

5. The method according to any one of claims 1 to 3, characterized in that the processing step includes oxidizing gas method between 350 and 550°C.

6. The method according to any one of claims 1 to 3, characterized in that the processing step includes oxidation in boiling brine between 120 and 160°C.

7. The method according to any one of claims 1 to 3, characterized in that the first stage includes a phase azotonaweglanie with the diffusion of nitrogen and carbon.

8. The method according to claim 7, characterized in that the first stage further includes a phase nitriding diffusion of nitrogen without the carbon diffusion.

9. The method according to any one of claims 1 to 3, characterized in that the first stage includes nitriding or azotonaweglanie in ionic liquid medium.

10. The method according to any one of claims 1 to 3, characterized in that the first stage includes nitriding or azotonaweglanie plasma method.

11. The method according to any one of claims 1 to 3, characterized in that the first stage includes nitriding or azotonaweglanie in the gas phase.

12. The method according to any one of claims 1 to 3, characterized in that the step of nitriding or azotonaweglanie carried out in a period of time amounting to between 10 minutes and 3 hours.

13. The way p is any of claims 1 to 3, characterized in that the step of nitriding or azotonaweglanie is carried out at a temperature of between 610 to 650°C.

14. The method according to any one of claims 1 to 3, characterized in that before the first stage, degreasing of parts.

15. The method according to any one of claims 1 to 3, characterized in that it further includes, before the first stage, the stage of preliminary heating of the workpiece between 200 and 450°C in the furnace during the time average of between 15 and 45 minutes.

16. The method according to any one of claims 1 to 3, characterized in that the workpiece is temporary oily protection when processing is completed.

17. The method according to any one of claims 1 to 3, characterized in that it also gives the processed detail the properties of wear resistance and resistance properties fouling.

18. Cookware, processed by the method according to any one of claims 1 to 17, containing a layer of nitrogen braunite or nitrogen martensite located between the nitride layer and the diffusion layer and having a hardness between the hardness of the nitride layer and the hardness of the diffusion layer.



 

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FIELD: metallurgy.

SUBSTANCE: parts are preliminary surface locally alloyed with nitride-forming elements. On surface of parts there is applied coating at laser heating to temperature T=690-710°C and it is conditioned during 3-4 hours. Further, there is performed low-temperature nitriding at heating to temperature T=570-590°C and conditioning during 6-8 hours in ammonia medium.

EFFECT: uniform on surface strengthened layer; reduced duration of steel parts nitriding; maintaining high hardness of layer.

1 tbl, 6 ex

FIELD: metallurgy.

SUBSTANCE: procedure for nitriding steel items in glow discharge consists in vacuum heating items corresponding to cathode in plasma of nitrogen of higher density. Plasma of nitrogen of higher density is formed in a near cathode area with a beam of electrons generated and accelerated with an auxiliary anode. Electrons emitted from an electron gun are directed to the anode and to the auxiliary anode generating electron gas flow facilitating collision of electrons with neutral particles and maintaining plasma existence. Velocity of electrons motion is controlled with the auxiliary anode connected to its own source of power.

EFFECT: intensified nitriding, increased contact durability and wear resistance of strengthened layer.

1 dwg, 1 ex

FIELD: mechanical engineering.

SUBSTANCE: following preliminary mechanical processing, crank-shaft is subject to induction heating and cooling due to heat conductivity in crank shaft core. As a result, the surface hardness is HRC 34-48. After that the surface is grinded and treated under low temperatures by chemical and thermal methods. Finally, the surface is mechanically processed.

EFFECT: reduced manpower effort during crank shaft production and required durability, strength, reliability, thermal resistance and wear resistance.

2 dwg

FIELD: food industry.

SUBSTANCE: device comprises a convex pan for the product retention, a bowl with hot coals for the pan heating and a stand for the pan and the bowl retention. The stand is designed in the form of a closed chamber containing side walls having undercuts matching the pan shape in the upper part and a horizontal platform with a cut-out for installation of the bowl with hot coals. Cut-outs are made in the stand body below the horizontal platform for convenient hand gripping with the view of the device transportation and for air delivery with a view of the table bearing surface cooling. Cut-outs for oxygen access to the hot coals are made over the horizontal platform.

EFFECT: enhanced utilisation of heat generated during fuel burning and improved fire safety.

3 cl, 1 dwg

Thermo-chargrill // 2509518

FIELD: personal usage articles.

SUBSTANCE: invention relates to devices for cooking food products using charcoals. The thermo-chargrill contains two long and two short side walls, an underbody, a grate, two flap-down grids and legs. The flap-down grids are attached to the long side walls near the short side walls by way of a pivot connection. The side walls are double-walled and are installed with a gap between the external and the internal side walls. The thermo-chargrill is collapsible. The detachable underbody is rectangular and designed in the form of a chute with horizontal support shelves. There is a damper with a handle mounted on each short side wall from the bottom. The grate is designed in the form of a rectangular perforated tray with side boards that is installed resting on the detachable underbody. There are at least two threaded holes made in the legs. During the side walls installation on the legs the holes made therein match the threaded holes in the legs. Threaded screws with a handle are inserted through the holes in the side walls and into the threaded holes. The flap-down grids are formed by a rectangular wire frame and wire rods.

EFFECT: additional rigidity, strength, reduction of overall dimensions during transportation and facilitation of the chargrill maintenance process after usage.

5 dwg

FIELD: personal use articles.

SUBSTANCE: invention relates to devices for cooking food using coal. The chargrill comprises two long and two short side walls, a bottom and legs. The side walls are made double-walled with inner and outer side walls mounted with a gap. The chargrill is made demontable and comprises two rectangular long side walls, two short side walls, four legs and a removable bottom. Each side wall comprises inner and outer walls joint together. Each outer wall of long side walls is made longer than the inner wall connected to it to form on the side of lateral edges of projecting flat ends in each of which there are at least two openings. The length of the inner wall is equal to the distance between the legs to which it is attached. The length of the outer wall of the long side wall is equal to the length of the chargrill and the lower part of this wall is made bent to the side of the inner wall connected to it to form the shelf projecting into the chargrill after its assembly.

EFFECT: reduction in size of the chargrill during its transportation and facilitation of the process of caring for the chargrill after use.

5 dwg

FIELD: personal use articles.

SUBSTANCE: versions of the barbecue grill have a handle attached to the outer surface of the cooking chamber and a thermal shield attached both outside adjacent to the cooking chamber and inside the cooking chamber, and the part of the thermal shield has a location detached from the cooking chamber to form a thermal barrier for the conventional heat between the heated volume of the cooking chamber and the handle.

EFFECT: thermal shield for a barbecue grill is designed to reduce heat transfer from the heated volume to the handle of the barbecue grill.

13 cl, 5 dwg

FIELD: personal use articles.

SUBSTANCE: trolley, made with the ability to maintain the grill, including the grill boiler. The trolley comprises two connecting elements with curved grooves to accommodate tubular U-shaped elements. The connecting elements can be in the form of two similar (but not necessarily identical) halves which are joined together to accommodate the frame elements. The tubular notches of the connecting elements maintain resistance to movement (such as rotation and tilt) in at least two directions. The connecting elements fix the frame elements in place by internal protrusions that are inserted into the corresponding notches or holes in the frame elements. Additional rigidity is attached to the trolley by one or more side tables that are both structural elements and functional tables. Thus, side tables serve as crosses between two frame units. Cover of the grill can easily be tilted back to rest on the cover supports under the lower edge and the points of contact on the side tables.

EFFECT: increased structural rigidity.

31 cl, 9 dwg

Universal dishware // 2434567

FIELD: personal use articles.

SUBSTANCE: invention is related to kitchenware for cooking food products. Universal dishware for cooking food products is designed for use at home and in catering facilities. Dishware contains a cast iron reservoir of semi-oval shape (of a boiler type) with handles; an additional replaceable cylindrical reservoir from stainless steel with handles and a latticed bottom, on which there are vertically fixed sharpened rods; a cover with an inbuilt electric source of heat radiation with a controller and a temperature sensor, and an indicator of temperature in working volume of a dish inbuilt into a cover's handle, at the same time the contacting flanges of reservoirs and covers are mutually matchable; an insert lattice with a handle and a flat ceramic insert-disc with a handle installed into the cast-iron reservoir depending on the method of products cooking.

EFFECT: improvement of quality of food cooking (without burning) and making it possible to prepare different meals.

5 cl, 1 dwg

FIELD: food industry.

SUBSTANCE: IR furnace can be used for processing food products including meat. Furnace has case provided with isolation, working chamber, inspection hole made of heat-resistance material to watch is product is ready, top IR-radiators mounted in device for adjusting its position, lower IR radiators mounted stationary, tray mounted in grooves built in side walls of working chamber to fix distance from radiators to object, mode controller and power application voltage controller. Timer is provided onto panel of furnace. Furnace can be used as at cafes and restaurants and at home for cooking as well as heating ready dishes.

EFFECT: simplified design.

The invention relates to household appliances for baking

The invention relates to portable universal household appliances for budget cooking or heating food with power supply from a low voltage source with a voltage of 12, 24, 36 and can be used in different settings, including at home, at the cottage, in vehicles, railway transport, sea and river ships, restaurants, cafes, in the field for barbecue, heating products, water, baby food, soups, tea, and so on), drying mushrooms, bread

Smoker-oven // 2197166
The invention relates to household appliances, in particular for mobile marching smokers and kitchens

FIELD: food industry.

SUBSTANCE: IR furnace can be used for processing food products including meat. Furnace has case provided with isolation, working chamber, inspection hole made of heat-resistance material to watch is product is ready, top IR-radiators mounted in device for adjusting its position, lower IR radiators mounted stationary, tray mounted in grooves built in side walls of working chamber to fix distance from radiators to object, mode controller and power application voltage controller. Timer is provided onto panel of furnace. Furnace can be used as at cafes and restaurants and at home for cooking as well as heating ready dishes.

EFFECT: simplified design.

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