JPS5919195B2 - Method and device for cleaning treated materials such as oil-stained steel parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for cleaning treated materials such as oil-stained steel parts before heat treatment.

Conventionally, when heat treating steel parts, etc., it is necessary to clean impurities such as oil adhering to the treated material before heat treatment, and methods for cleaning this treated material include chemical cleaning such as trichlene cleaning and alkaline cleaning. methods have been adopted.

This method has drawbacks such as the problem of drainage pollution caused by various cleaning solutions, the problem of cleanliness when the treated material has a complicated shape, and the need for a drying device as a post-processing device. On the other hand, some methods have been implemented to clean the treated materials by heating using exhaust gas or electric heating, but even with this method, there are problems with oxidation of the treated materials and the need for vaporized oil (huum) processing equipment. There was a problem that it was necessary to install it separately, and that the heat stored in the hum could not be effectively reused.

Furthermore, safety (explosion, etc.) due to vaporized oil (burum)
There was a problem. This invention was made in view of the above-mentioned problems, and its purpose is to reduce the residual O2 in the furnace to 4% or less by using combustion generated gas to remove the oil attached to the treated material. 5 convection heating to a temperature corresponding to the vapor pressure of By supplying part of the heat source to the treated material and discharging it outside the furnace through a heat transfer tube placed in the furnace, the treated material is reliably cleaned without oxidizing the treated material, and safety during operation is ensured. It is an object of the present invention to provide a method and an apparatus for cleaning treated materials such as oil-stained steel parts, which can secure and effectively utilize retained heat during combustion treatment of vaporized oil and the like. Hereinafter, this invention will be explained in detail with reference to an embodiment shown in the drawings.

1 and 2 respectively show a front vertical sectional view and a side vertical sectional view of a specific device for realizing the cleaning method according to the present invention, and both sides of the furnace body 1 constituting the cleaning device are shown in FIG. Doors 4 and 5 for loading and extracting processing materials are provided, each of which is open and rotatable by hydraulic cylinders 2 and 3 provided on both sides thereof.

In the furnace width direction, approximately at the center of the floor inside the furnace body 1,
The upper plate part 6 is formed by the wall material 6 having a roughly U-shaped cross section.
A processing chamber 7 is provided, which communicates with the inside of the furnace main body 1 constituting a processing material heating section, which will be described later, through an opening 6b of a predetermined width formed at the connection part with the side wall 1a of the furnace main body 1 in a, and a recess is provided on each side of the processing chamber 7. 8a and 8a are formed.

In addition, guide rails 9, 9 are installed in the furnace length direction, and a pair of skid rails 10, 10 are provided at a constant interval from the guide rails 9, 9, and a processing material mounting section is provided. It consists of On the skid rails 10, 10, processing materials 11 such as steel parts with oil or the like adhering to them are charged from the processing material charging door 4 side by an appropriate loading section (not shown), and the processing materials 11 are placed on the pedestals 12. It is placed above the processing chamber 7 through the process chamber 7. Then, the processing material 11 absorbs the combustion generated gas from the burner parts 13, 13 provided in the lower part of the side wall 1a of the furnace main body 1 at positions corresponding to the recesses 8a, 8a.
An RC fan 14 provided on the ceiling wall 1b of the furnace body 1 performs forced convection heating to vaporize oil and the like adhering to the processing material 11. On the other hand, one end of the other side wall 1c inside the furnace main body 1, that is, the back side of the processing material 11, is connected to a hole in the upper plate portion 6a of the wall material 6 via a seal member 15, and the processing material 11 is A pair of radiant tubes 16 as heat transfer tubes communicating with the chamber 7 and having the other ends protruding upward through the ceiling wall 1b of the furnace body 1, respectively;
16 are provided.

Note that each radiant tube 16, 16 is fixedly supported on the side wall 1c of the furnace main body 1 by a support 17 and a fixture 18, and each radiant tube 16, 1
A recuperator 19 is provided above the other end of 6. The vaporized oil (fume) inside the furnace body 1 is introduced into the processing chamber 7 through the opening 6b by the combustion generated gas from the burner parts 13, 13, and at the same time, the vaporized oil (fume) etc. inside the furnace body 1 are introduced into the processing chamber 7 through the opening 6b. A burner section 20 provided at a position corresponding to the processing chamber 7, and a combustion air supply port 21 provided at the floor section of the furnace main body 1.
The combustion process is carried out using the combustion air supplied from the vaporized oil. This combustion exhaust gas is transferred to each radiant tube 16,
16 and are discharged to the outside of the furnace main body 1. In the above configuration, the combustion generated gas from the burner parts 13, 13 is stirred in the furnace by the R-C fan 14, and after the inside of the furnace is maintained at a predetermined temperature, oil etc. The treated material 11 to which impurities have adhered is placed on the pedestal 12, inserted into the furnace body 1, and placed on the skid rails 10, 10.

In order to prevent explosion due to vaporized oil (fume) and oxidation due to oxygen, the treated material
Forced convection heating is carried out for about 15 to 20 minutes to a temperature near the vapor pressure of the adhered oil, for example, about 400 to 500°C. As a result, the oil etc. adhering to the processing material 11 is vaporized and the processing material 11 is cleaned, but the residual amount in the furnace is about 4.
% or less, and heating of the treated material 11 is carried out in a short time of about 15 to 20 minutes, so safety during operation can be ensured and furthermore, the treated material 11 will not be oxidized. .

Note that since the treated material 11 is heated by forced convection, the treated material 1
1 can be kept constant, and the oil can be sufficiently vaporized. On the other hand, vaporized oil (fume) etc. vaporized from the treatment material 11 are transferred to the wall material 6 by the combustion generated gas.
is introduced into the processing chamber 7 through the opening 6b of the processing chamber 7.
The combustion process is carried out within the combustion chamber using air from the burner section 20 and the combustion air supply port 21.

This combustion exhaust gas is then transferred from the processing chamber 7 to both radiant tubes 16 and 1, as shown by arrows in FIGS. 1 and 2.
60 flows into one end side, both radiant tubes 16, 16
The gas is discharged to the outside of the furnace main body 1 from the other end. Here, since the combustion exhaust gas passes near the back of the treatment material 11, the combustion exhaust gas is provided to a part of the heating source of the treatment material 11, and therefore the combustion capacity of the burner section 20 is reduced accordingly. In other words, energy saving can be achieved.

Then, the treated material 11 that has been cleaned is... The material is extracted to the outside of the furnace main body 1 from the processing material extraction door 5 side by an appropriate extraction means (not shown) and transported to the next heat treatment step.

Furthermore, with the device according to this invention, the materials soaked in ordinary cutting oil can be processed into SNCM2l, SCM2l, Sl5CK.
, S45C and having a shape of φ22×80 mm was kept in the furnace at a furnace temperature of 450° C. for 218 minutes, subjected to a parts-off treatment, and then carburized and tempered in the following manner.

The carburizing treatment was as follows: carburizing: 900°C x 3 hr, quenching temperature: 87
0°C, quenching oil temperature: 60°C, carburizing specifications: surface carbon content 0.
It was carried out under the conditions of 8%° C. and carburization depth of 0.6 mm, and the tempering treatment was carried out at 130° C. for 3 hours.

As a result, in terms of carburization depth, surface hardness, and hardness distribution, each of the above-mentioned test pieces obtained the same result force z as in the case of conventional chemical pickling cleaning.

As described above, according to the method according to the present invention, treated materials such as steel parts to which impurities such as oil are attached can be removed to zero remaining in the furnace.
2 is 4% or less, and convection heating is performed for a predetermined period of time using combustion generated gas to a temperature close to the temperature corresponding to the vapor sweat of adhering oil, ensuring safety during operation and eliminating impurities such as oil. It is possible to reliably clean the treated material without oxidizing it by vaporizing it, while guiding the vaporized oil (huyum) etc. to a predetermined position with the combustion generated gas and burning it while adding combustion air. Since the heat of this combustion exhaust gas is indirectly used as a part of the heating source for the material to be treated and is discharged outside the furnace, it is possible to preheat the material to be treated at the same time as processing vaporized oil (fume), etc. Furthermore, since air or the like is not required to remove the vaporized oil in the furnace, energy can be saved accordingly. Further, according to the second invention, the cleaning device is provided in the furnace with a processing material heating section including a placing section for placing the processing material, a fan and a burner section, and a processing material heating section provided in the hearth section for heating the processing material. a processing chamber which has an opening communicating with the processing section, and which is equipped with a burner section and a combustion air supply section and burns vaporized oil, etc., and one end of which communicates with the processing chamber, and which is connected to the processing material heating section of the processing material heating section. Since the heat exchanger tube is configured with a heat transfer tube whose other end is led out of the furnace through the vicinity, the method according to the first invention can be realized within the furnace and with an extremely simple configuration.

Further, since the heat transfer tube is disposed within the processing material heating section, the heat of the combustion exhaust gas can be utilized extremely effectively.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of an apparatus for concretely implementing the method of the present invention, and FIG. 2 is a cross-sectional view taken along line I-1 in FIG. 1. 1...furnace body, 6...--wall material, 6b...
...Opening, 7...Processing chamber, 9...
・Guide rail, 10... Skid rail, 1
1... Treated material, 13... Burner part, 1
4...Fan, 16...Radiant tube, 20...Burner section.

Claims (1)

[Claims] 1. Processed materials such as steel parts that have impurities such as oil attached to them are combusted to a temperature close to the vapor pressure of the attached oil etc. so that the residual O_2 in the furnace is 4% or less. Convection heating is performed using gas for a predetermined period of time to vaporize the impurities from the processing material, while guiding the vaporized oil etc. to the processing chamber using the combustion generated gas,
An oil-stained steel component characterized in that combustion treatment is performed while adding combustion air, and the heat of this combustion exhaust gas is indirectly supplied to a part of the heating source for the treated material and discharged outside the furnace. How to clean treated materials such as 2. A processing material heating section that includes a placing section for placing processing materials such as oil-stained steel parts in the furnace, a fan, and a burner section, and an opening provided in the hearth section that communicates with the processing material heating section. and a processing chamber equipped with a burner section and a combustion air supply section, one end of which communicates with the processing chamber, passes through the vicinity of the processing material of the processing material heating section, and the other end leads out of the furnace. 1. A cleaning device for cleaning treated materials such as oil-stained steel parts, characterized by comprising a heat exchanger tube made of