JPS5953688A - Method for removing oxide scale from metallic surface - Google Patents

Abstract

PURPOSE:To remove easily oxide scale from a metallic surface without damaging said surface by irradiating the oxide scale deposited on metallic surface with laser light in mixed inert and reducing atmospheres and removing the oxide scale. CONSTITUTION:A metallic plate 2 having thereon with deposited oxide scale 1 is moved in an arrow direction and a gaseous mixture of an inert gas and a reducing gas is ejected through a blowing nozzle 4 from a cylinder 7 onto the surface of the plate 22. The ejected gaseous mixture is released from a space 8 through a dust collector 11 into the atmosphere. The laser light C adjusted to prescribed irradiation conditions in this state is introduced into a duct 3 and irradiates the surface of the plate 2 which is receiving the ejection of the gaseous mixture. The scale 1 is instantaneously heated to a high temp. and blower up in the space 8; at the same time, the scale releases oxygen which is recovered by the suction effect of a blower 12 into a dust collector 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for removing acid benol present on the surface of metal.

Since TLR, shot blasting has been used to remove oxide scale attached to the metal surface, but this method requires shot or grid blasting on the metal surface to remove scale. In order to remove the scale (and maintain the necessary surface use of the metal), the injection of the projectile material γI゛1, the projection speed, the projection distance 1η11, the projection 'J.I density, etc.
r: I had to adjust the blasting conditions. However, holding these conditions and doing a shot 1, plus 1, is a Kokubu IF, and a considerable amount of variation occurs, and this variation directly leads to contradictory variations in the descaling rate and metal surface, resulting in 11 marks. On the other hand, it is common knowledge that considerable variation occurs in the surface roughness of 91(, 1.). As the removal of a small amount of scale is required, the Dobras 1 method has reached its limit.

The present invention was made with the purpose of resolving these problems.
``This method removes more than one oxide scale from the metal surface by irradiating laser light in a concave atmosphere.

The present invention will be explained below based on examples.

4.1 The oxide scale (1) moved in the direction of the arrow via a conveyance device fFt (not shown) is deposited 1 and the total mass ()i
On the -Jl side of ('/here), a beam duct (3) is arranged 1 for guiding laser light (C) generated by a not-shown Rayleigh oscillation field and adjusted by various adjustment devices.
'l, and the beam duct I-(3) is attached to a metal plate (2
) is provided so as to be inclined in a direction opposite to the direction of movement Ji. Furthermore, at the rear of the lower end of the beam duct (3) there is a nozzle (4) that can blow gas onto the surface of the metal plate (2).
) is Ir'! The nozzle (4) is connected to a gas cylinder (7) via a pipe (5) and a valve (6).

The gas used in this example is a mixed gas of argon, which is an inert gas, and hydrogen, which is a reducing gas. Furthermore, a metal plate (2) is attached to the front of the lower end of the beam duct l-(3).
A hood (9) constituting a space (8) is provided on one side, and the hood (9) includes a duct (10) and a dust collector (
11) to the IJl fan (12).

Next, to explain the operation, in Fig. 1, the metal plate (2) with oxide scale (1) deposited on its surface is moved in the direction of the arrow, the valve (6) is opened, and the mixed gas is passed through the nozzle (4). The liquid is ejected towards the surface of the metal plate (2) through the metal plate (2).

- The mixed gas ejected in the direction is collected from the space (8) by operating the 1J1 wind fan (12) to collect 1ffil (]
In this state, various lasers (not shown) generated by a Rayleigh oscillator (not shown) are tuned through the device 1 (1). A laser beam (C) adjusted to predetermined irradiation conditions is introduced into the beam receiver 1-(3),
1111 of the previous jli, the laser beam (C
) is irradiated, in the atmosphere of the injected mixed gas, the oxide scale () becomes high temperature during the IR, evaporates or melts, and flies into the space (8) by the Ili'5 MC of the jl+11 resultant force. 1-Gal.

The mixed gas includes argon, which is an inert gas, and 1. '+'f
Since it is a mixture with hydrogen, which is a phosphorus gas, it is possible to prevent +1 arsenide scale from being generated on the surface of the metal plate (2) after the oxide scale (]) has been removed.

In addition, the oxidized scale of metal has a higher absorption rate for laser light than the metal itself;
Once, □ Laser light irradiation conditions such as irradiation time, etc. 4. It is possible to evaporate or melt only the oxide scale without damaging the metal base. Any type of laser beam, such as C02 laser light or YAG laser light, may be used for J-engineering, but the conditions for irradiation depend on the type of laser light,
It is necessary to select the metal species Yi and the oxide scale (1) depending on the adhesion state, etc., but the laser beam (C) selected for the irradiation conditions does not vary and is continuous in a constant state. irradiated.

In this way, the vapor or molten particulates of the sharp oxide scale are cooled and become fine solid particles, which float in the space (8) and at the same time release oxygen in the reducing atmosphere. It is collected by the dust collector (11) after receiving the flow from the JI wind machine (12) during the first fire.

On the other hand, when the oxide scale (1) is removed, the surface of the metal plate (2) is hardly damaged as mentioned above, and the generation of oxide scale 11f is prevented by hydrogen gas and argon gas, so that the descaling rate and metal Board (2
) has no variation in surface roughness.

As is clear from the explanation in 11 below, the present invention provides a metal surface with 4
= J Is it bad for the oxide scale that is attached? +% ('l:
4) In an ambient and reducing atmosphere
・For irradiation: It is used to remove acid IP scale, and by selecting and adjusting the irradiation strip ffl to be applied to the instep from J7. It is possible to remove the oxidized three-reel inside the cylinder without damaging the RF surface.

In the embodiment, a mixed gas of argon and hydrogen 4 was used to prevent the generation of 111 oxide scale, but a middle column gas of argon gas or hydrogen gas 4v fJi may also be used.

[Brief explanation of the drawing]

FIG. 1 is a drawing of an apparatus according to an embodiment of the present invention. reactor.

Claims (1)

[Claims] At t7. the oxide scale deposited on the surface of the metal is irradiated with laser light in a mixed atmosphere of inertness and reduction; l+j°Q and Zuroj>
Method for removing oxide scale from metal surfaces.