SU86994A1

SU86994A1 - The method of isothermal treatment of steel products and device for implementing the method

Info

Publication number: SU86994A1
Application number: SU406509A
Authority: SU
Inventors: С.Д. Богословский
Original assignee: С.Д. Богословский
Priority date: 1949-10-13
Filing date: 1949-10-13
Publication date: 1949-11-30

Description

Предметом изобретени вл етс способ изотермической обработки стальных изделий при нагреве их током высокой частоты и устройство дл осуществлени способа.The subject of the invention is a method of isothermal treatment of steel products when heated by their high frequency current and a device for carrying out the method.

Обычно изотермическую обработку стальных изделий провод т при нагреве их в пламенных, электрических и других печах, а также в сол ных ваннах с охлаждением в расплавленной среде, например в различных расплавленных сол х, в свинце и т. д.Usually, isothermal treatment of steel products is carried out by heating them in fiery, electric, and other furnaces, as well as in salt baths cooled in a molten medium, for example, in various molten salts, in lead, etc.

Согласно предлагаемому способу термической обработки стальные издели предварительно нагревают до температуры, соответствующей наибольшей устойчивости аустенита, определ емой дл каждой маркп стали по кривой температура - превращение - врем . После этого издели нагревают под закалку индуктором тока высокой частоты до температуры выше верхней критической точки. Затем нагретый поверхностный слой охлаждают до температуры подогрева всей детали, после чего производ т резкое охлаждение детали до комнатной температуры.According to the proposed heat treatment method, steel products are preheated to a temperature corresponding to the greatest stability of austenite determined for each steel mark by the temperature-transformation-time curve. After this, the product is heated for quenching by a high frequency current inductor to a temperature above the upper critical point. Then, the heated surface layer is cooled to the preheating temperature of the entire part, after which the part is cooled rapidly to room temperature.

Дл ограничени времени выдержки при нагреве издели / (фиг. 1) под закалкой в индукторе 2 и последующего быстрого охлаждени в сол ной ванне 3 или окончательного охлаждени в вод ной ванне 4 изделие подвешивают на оправке 5 и удерживают до окончани нагрева под закалку при помощи электрозащелки 6.To limit the exposure time for heating the product / (Fig. 1) under quenching in inductor 2 and subsequent rapid cooling in a salt bath 3 or final cooling in a water bath 4, the product is suspended on a mandrel 5 and held until electric heating is completed for quenching 6

На фиг. 2 показаны теплоизолирующа крышка 7 и теплоизолирующее дно 8, которые позвол ют выравнивать температуру поверхностного сло издели Я нагретого под закалку при помощи индуктора 10 до температуры подогрева всей детали. Изделие 9 помещают на оправку //, имеющую переходную втулку 12, котора надеваетс на посадочный валик 13.FIG. 2 shows the heat insulating cover 7 and the heat insulating bottom 8, which allow to equalize the temperature of the surface layer of the product I heated for quenching using inductor 10 to the heating temperature of the entire part. The article 9 is placed on a mandrel // having an adapter sleeve 12, which is put on the landing roller 13.

Предмет изобретени Subject invention

Claims

1. The method of isothermal treatment of steel products, characterized in that, in order to use high-frequency current for thermal products, they are heated in a furnace to a temperature of the highest value of auteutite. determined for each steel grade by the curve, temperature-transformation - time, then put the product in the current inductor; high frequency to heat the surface layer above the critical point, cool this heated layer to the preheat temperature of the entire part and, after equalizing the temperature, be sharply cooled to room temperature.

2. Acceptance of isothermal treatment ed. 1, characterized in that, in order to limit the dwell time during heating for quenching in the inductor and the subsequent rapid cooling of the product in a salt bath having the temperature of aeutinite’s greatest stability and final cooling in a water bath, the product is heated on a mandrel held until heating for quenching with an electric strike,

3. A device for carrying out the method according to claim 1, characterized in that, in order to accelerate the equalization of the temperature of the surface layer with the preheating temperature of the entire part, the inductor is equipped with a heat insulating bottom and top cover.