JPS5855247Y2 - Local annealing treatment equipment after welding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for local annealing after welding, and particularly to an apparatus for annealing a welded portion of a metal container or a metal strip.

Conventionally, for example, in a continuous processing line for metal strips, the ends of strip coils are joined together by welding.
Although subsequent processing equipment is continuously fed in, if the welded part is fed in as is, the stress remaining in the welded part may cause cracks or breakage in the welded part. be.

Therefore, the welded portion is annealed in advance.

Currently, there are two methods for this, one in which an induction heating device, a cooling device, and a drying device are sequentially arranged in the strip conveyance line and the strip is passed through the line, and the other in which only a burner is provided.

The former method can perform annealing with high precision, but the size of the device is large and the equipment cost is high.

Moreover, the welded parts of the metal strip had to be moved one after another, making the operation cumbersome.

The latter method has low equipment costs, but has the drawbacks of requiring manpower and poor accuracy.

Therefore, the inventors of the present invention conducted research in order to solve the latter drawback and provide a device that can perform accurate annealing treatment at low equipment cost and also automatically.

In general, taking the case of local heating of a strip as an example, the local material temperature is determined by the heat input Qi to the local area and the amount of heat released from the local area [the amount of heat escaping by conduction, convection, and radiation (each Qcd
, Qcv, QR): ].

That is, when Qi>QCd+QCV+QR, Qi=QC
The local material temperature increases until it reaches d+QCV+QR.

Now, when performing annealing treatment, as shown in Figure 1, when the local temperature of the material reaches a certain temperature TA, for a certain period of time,
The local temperature must be maintained at temperature TA.

Therefore, even if the above temperature TA is reached, the heat input Qi and the heat radiation amount Qc
When d + Qcv + Q R is not balanced,
That is, when Qi>Qcd+Qcv+QR, the heat input Q
By reducing i, Qi = Qcd + Qcv + Q
It is necessary to make it R.

It is.

Heat input Q in a short time using burner combustion amount (fuel supply amount)
It is extremely difficult to adjust i, which requires an accurate temperature measuring device and control instrument, and it is difficult to control with a fast response speed.

On the other hand, further analysis of equation (1) shows that the thermal conductivity ht is a function determined by the velocity of the combustion gas when it hits the strip surface.If the burner combustion amount is constant, the gas velocity and the gas temperature Tg are determined by the burner velocity. and the distance S to the strip surface, ht=f(v), v, respectively.
=g(S), Tg=h(S), equation (1) becomes Qi=f(g(S)J・SA・(h(S)−T Aj
−(2).

As is clear from equation (2), the heat input Qi is a function determined by the distance S from the burner to the strip surface, so S
It is confirmed that the heat input Qi can be adjusted by controlling the .

The present invention was developed based on the above theory and the results of confirmation experiments, and a pair of upper and lower line burners are used to transport the processed material so that the welded part that extends linearly in the width direction can be heated simultaneously from the front and back sides of the welded part. It is connected by a synchronized means that is installed opposite to the line and moves at a constant speed in a direction perpendicular to the conveyance line and in opposite directions, and after heating the welding part for a certain period of time, the amount of heat released QCd + QC ■An attempt is made to provide a post-weld annealing treatment device that can simultaneously maintain the welded portion at a constant temperature by simultaneously separating the welded portion in a direction perpendicular to the welding line to a position where QR and heat input Qi are balanced. It is something to do.

Next, the present invention will be described with reference to the attached drawings, which are one embodiment of the present invention.

FIG. 3 is a partially cutaway side view of an annealing treatment apparatus M for metal strips after welding according to the present invention, in which a heating device and a cooling device are mounted on a trolley, and FIG. A sectional view is shown in which the cart 1 is positioned in front of an accumulator (not shown) and moves on rails 2.

The heating device T consists of line burners 3.3 arranged above and below, and inner and outer hoods 4, 6 and 7 which cover the line burners 3 from above and below, respectively.

That is, among the pair of line burners 3, 3, the upper burner 3 is doubled by the inner hood 4 and the outer hood 6.

The lower burner 3 is surrounded by a hood 7.

Of these, both ends of the hoods 6 and 7 are as shown in FIG.
The strips overlap each other in double layers to prevent outside air from entering from the ends.

As described above, both ends of the hood 7 are located inside the upper outer hood 6 and are mounted so as to be vertically movable.

Further, in the outer hood 6.7, opposite ends in the strip width direction excluding both ends of the strip have a gap 5 larger than the thickness of one metal strip W when they are closest to each other, and this is a passage through which the metal strip W is inserted. 8 (see FIGS. 4 and 6), and a heating chamber A is formed within the hoods 4 and 7.

The heating device T having the above configuration includes its upper and lower hoods 4,
6.7 is supported so as to be movable in the lateral direction by pulleys 12 on two horizontal frames 10.11, each of which is moved up and down by a tuning means 13, which will be described below.

Each side of the horizontal frame 10.11 has a rack 14a.
, 14b, which mesh with the pinions 16 provided in each of the two pillars 15 erected on both sides of the truck 1 to constitute the tuning means 13 as shown in FIG.
a is connected to a rod 19 of an elevating cylinder 18 located above the support column 15.

Therefore, by the operation of the lifting cylinder 18, each of the hoods 4, 6.7, together with the upper and lower line burners 3, 3, move toward and away from each other at the same speed in synchronization with each other in opposite directions (perpendicular to the metal strip W). be.

Further, an exhaust fan 20 is attached to the ceiling plate 17 attached to the pillar 15, and the exhaust port 9 provided at the upper part of the outer hood 6 fits into the exhaust duct 21 of the exhaust fan 20 with some play. ing.

Note that 22 is a damper.

Further, the diameters of the nozzles located on both sides of the line burners 3, 30 are slightly larger than those in the center, or the number thereof is increased, so that the amount of heat at both sides is larger than that at the center.

The cooling device C is located on the accumulator side of the heating device T, and like the heating device T, a shower is installed in a pair of upper and lower frames 10a, 10a connected by a tuning means 13a located in two pillars 15. It consists of a structure in which upper and lower hoods 24 and 25 are attached with built-in devices 23 and 23,
The upper and lower hoods 24 and 25 are moved closer and further apart by the operation of a cylinder 26 attached to the upper frame 10a.

A blocking plate 27 is attached to the front and rear side walls of the upper and lower hoods 24.25 via repellent means 28, and closes the gap between the metal strip W and the upper and lower hoods 24.25.
Prevents shower water from splashing outside.

Additionally, dryers 29 and 30 are provided outside the shielding plate 27 to blow out air toward the metal strip W.

Note that the cooling device C may use gas as a refrigerant, and in this case, the dryers 29 and 30 are unnecessary.

Under normal conditions, the metal strip W passes between the line burners 3, 3 and between the shower devices 23, 23, and is sent via an accumulator to the subsequent processing line.

Next, the operation of the apparatus M for annealing a metal strip after welding having the above configuration will be explained.

When the joint of the metal strip W joined by welding reaches a predetermined position directly below the burner, the strip stops,
On the other hand, the accumulator is operated to continue feeding to the subsequent processing device.

Next, the exhaust fan 20 is activated, the burner 3 is ignited, the lifting cylinder 18 is activated, and the line burners 3, 3 are activated.
close to the seam.

As mentioned above, the outside of the line burners 3, 3 is the hood 4,
6.7, the hood effect provides heat insulation to the device, and combustion gas is ejected from both sides of the metal strip W, thereby preventing cold air from being drawn in from the ends.

Further, since the amount of heat at both ends of the line burner 3 is larger than that at the center, the entire joint is heated uniformly by these actions, and the temperature rises.

When the welding part reaches a predetermined temperature, the lifting cylinder 18 is operated to move the line burners 3, 3 at a constant speed from the metal strip W to the position where the amount of heat dissipated from the metal strip W and the amount of heating are balanced. The welded portion is maintained at a predetermined temperature for a predetermined time at a distance perpendicular to W.

In the above case, since the amount of heat reached by the line burner 3 at the distance from the metal strip W and the amount of heat dissipated from the metal strip W are set in advance by experiment, the heating time and the separation distance of the line burner 3 are also known, and the above operation is performed. All can be done accurately and easily using simple control instruments such as timers.

After the welded area is kept uniformly heated for a certain period of time as described above, the trolley 1 is moved and the welded area is cooled with water by the shower device 23.23.

Thereafter, the shielding plate 27 is retracted up and down, and the welded portion is dried with the dryer 30, thereby completing the annealing process.

When the annealing process is completed as described above, the accumulator may be stopped to return to its original state and the metal strip W may be sent to a subsequent processing device.

As is clear from the above explanation, according to the present invention, a pair of line burners are arranged facing each other and can be moved at the same speed in conjunction with each other in opposite directions using a tuning means, so that the heating temperature of the welded part can be increased. is determined by the heating time, and the annealing treatment after welding can be performed by maintaining the heating temperature by the relative distance between the burner and the welded part.If the heating time and moving distance are calculated in advance, It has the advantage that the annealing process can be performed accurately and quickly using a simple control instrument such as a timer.

In addition, if the line burner is covered with a hood and the combustion force is ejected from both ends of the welded part through passages formed in the hood, the heat loss occurring at the ends of the welded part can be compensated for. The welding area can be heated uniformly.

[Brief explanation of the drawing]

Fig. 1 is a graph showing material temperature changes during annealing treatment after welding, Fig. 2 is an explanatory diagram for explaining the basic operation of the present invention, and Fig. 3 is an annealing process for carrying out the present invention. A partially cutaway side view showing an example of the device, FIG. 4 is a cross-sectional view taken along line I■-■V in FIG. 3, FIG. 5 is a cross-sectional view taken along line ■-■ in FIG. 3, and FIGS. 6 and 7. FIG. 2 is an explanatory diagram showing the flow of combustion gas inside the hood. M...Annealing treatment equipment after welding, T...
Heating device, C... Cooling device, W... Treated material (metal strip), 1... Trolley, 3...
... Line burner, 4, 6.7 ... Hood, 13 ... Tuning means, 14 a, 14 b.
...Rack, 16...Pinion, 18.
...Lifting cylinder, 21...Duct.

Claims (1)

[Scope of utility model registration request] A pair of upper and lower line burners connected by a coupling mechanism are mounted on a trolley that can run along the conveyance line for processed materials, so that they move toward and away from predetermined positions in synchronization with each other at a constant speed in a direction perpendicular to the conveyance line. A local annealing treatment device after welding, characterized in that it is mounted on a column.