JPS5987943A - Method and device for thickening pipe material - Google Patents

Abstract

PURPOSE:To obtain a uniform thickened part whose thickened amount to the inside diameter side is small, by heating locally a part to be thickened of a pipe by high-frequency induction heating, controlling its temperature gradient, and subsequently, swaging by applying a compressive force in the axial direction of the pipe. CONSTITUTION:A pipe material 1 is passed through a heating coil 13, both the ends are fixed between a press head 4 and a hydraulic cylinder 6, and the coil 13 is positioned at a thickened part by moving a current control transformer 12. Subsequently, the frequency of a high frequency current for determining an inside and outside diameter distribution ratio of the widened amount is set, induction heating of the pipe material 1 by a high-frequency oscillator 10 and the coil 13 is started, its surface layer part is set to a high temperature, and also a temperature gradient is given in the plate thickness direction. When it reaches a prescribed temperature, swaging is executed by compressing the pipe material 1 in the axial direction by the cylinder 6, and thereafter, desired heating is continued, and the heating width is controlled by jetting water from a hole 13a of the coil 13. In this way, the thickening which reduces the thickened amount to the inside diameter side can be executed.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a method and apparatus for increasing the thickness of a tube material, and in particular to a method and apparatus for increasing the thickness of a tube material, and in particular, it relates to a method and an apparatus for increasing the thickness of a tube material, and particularly to a method and an apparatus for increasing the thickness of a tube material. The present invention relates to thickening processing, methods and apparatus.

[Prior art]

Conventionally, the J11 method for increasing the thickness of the control material is to apply compressive force in the axial direction of the tube to increase the thickness of the l-1i material. Are known.

FIG. 1 is a perspective view showing a pipe material whose thickness has been increased by a conventional thickness increase processing method.

In this FIG. 1, 1 is the previous month, and 2 is irregular deformation such as buckling and wrinkles that has occurred in this green material 1.

As is clear from Fig. 1, if the swaging process is performed only by applying compressive force, that is, by simple compression process, irregular deformation 2 such as buckling and wrinkles will occur in the pipe material 1, resulting in uniform thickening. Machining could not be achieved and this was the cause of defects.

The present inventors have previously proposed a method for cutting the 1a neck wall, which eliminates the drawbacks of the prior art described above and achieves uniform pipe wall processing without irregular deformations such as buckling and wrinkles; (Special) Odesho 5 who developed =tyt which is directly used in implementing this method.
7-139182).

The feature of the blue thickening/JIJ method that the present inventors previously developed is that the areas to be thickened are successively heated locally, and the above-mentioned burrs are removed at a foot speed. By performing the swaging process by applying compressive force, the above-mentioned
It is made to increase the thickness of the processed part of the stomach.

The features of the previously developed thickening processing device include a stepping cylinder that can compress the tube in the axial direction at a constant speed with its spindle, and a stepping cylinder located on the outer periphery of the tube. The tube is provided with an annular heating coil that is disposed and movable along the axial direction of the tube.

The above-mentioned above-mentioned present invention A has been developed beforehand.

Uniform thickening processing is now possible without wrinkles or other irregular deformations.

By the way, in the above-mentioned thickness increasing process, the amount of thickness increase occurs on the outer side and the first lid diameter side, but especially when the inner diameter of the pipe material is small, the thickness increase on the inner diameter side 1) If the rate of decrease in the flow rate of the fluid flowing through the control system is too large, cavitation may occur in that area and there is a risk of corrosion during use, which should be further improved.

[Purpose of the invention]

The present invention improves the above-mentioned problems and eliminates wrinkles.

A uniform thickness increase amount without irregular deformation such as buckling [a pipe material that can be achieved in one machining process and can reduce thickness increase on the inner diameter side], d wall processing method, and this method. Its purpose is to provide equipment that can be used directly in implementation.

[Summary of the invention]

The 114th formation of the pipe material thickening method according to the present invention is as follows:
The part of the pipe material to be thickened 7JO is successively locally heated using high-frequency induction heating so that the surface layer of the pipe material reaches a high temperature and a temperature gradient is created in the outside diameter part of the pipe material. By applying compressive force in the axial direction and swaging, the thickness of the thickened portion is increased.

In fact, the construction of the pipe material tightening device d according to the present invention includes a load device capable of compressing the control in the axial direction, and a load device disposed so as to be located on the outer periphery of the pipe material. It is equipped with a frequency control rock that can control an annular heating coil movable along the axial direction of the shrine.

More specifically, the method for increasing the thickness of a tube according to the present invention is as follows.

A combination of high-frequency induction heating and forced cooling is used to locally heat the pipe material, and by applying compressive force to the pipe material, the deformation range is limited, and uniform growth is achieved without irregular deformation. Meat □ iu processing is allowed] as the Jth item.

In addition, the penetration depth changes depending on the frequency of the high-frequency current and the size of the pattern, and when the penetration depth becomes shallow, a temperature gradient occurs in the thickness direction of the heated object, and the high-temperature side of the heated object ( By actively utilizing the phenomenon that the deformation resistance of the surface layer (surface layer) is small and the deformation resistance of the low-temperature side becomes large, creating a gradient of liquid resistance in the plate thickness direction, the frequency of the high-frequency current in the high-frequency induction heating is increased. Well, it's a board. desired temperature in the direction,
By setting so that a gradient is obtained, the amount of increase in thickness [
)] The outer diameter distribution ratio (-the amount of thickness increase to the outer diameter side/the amount of thickness increase to the inner diameter side) is controlled by 'lIj, and the amount of shoulder thickness to the same diameter 1ij is reduced.

[Embodiments of the invention]

Hereinafter, the present invention will be explained by examples.

FIG. 2 shows an example of a sieve material thickening processing apparatus used for the pipe material thickening processing method according to the first embodiment of the present invention;
This is a partial cross-sectional view that does not clearly show the benefits of thickening.

In this FIG. 2, ] is the pipe material to be thickened,
4 is a press bed provided with a positioning part 4 for positioning one end of the control 1; 3 is a play F on which a hydraulic cylinder 6, which will be described later, is attached to its side (left side in FIG. 2); 521151 ) &:j:,・I'J i
It is a support that can be fixed at a position facing each other at a fixed distance and can receive the reaction force of the compressive force, which will be described later.

The support column 51] also serves as a guide for the axial movement of the transformer 12, which will be described later.

J-3 is arranged so as to be located on the outer periphery of the pipe material 1,
An annular addition that can heat this tube material 1! (This heating coil 13 is a transformer 1 shown in FIG.
2, it has a 6-piece capacity that moves along the axial direction of the pipe material 1,
Cooling water 14 for cooling the heating coil is provided on one side of the inner diameter surface (the side opposite to the forward direction of the heating coil 13 shown by the arrow).
Injection ports 13a for injecting a portion of the liquid toward the tube material 1 at an angle of 45° are drilled and distributed in the circumferential direction.

The heating coil 13 is equipped with a two-color thermometer (not shown) that can detect the temperature of the heating section of the control unit 1. A transmitting section (not shown) is provided that emits a signal when the temperature of the heating section reaches a preset temperature. 15 is a cooling water pipe that supplies cooling water 14 to the heating coil 13.

10 is a high frequency oscillator that generates a high frequency current; 11 is a frequency controller that can control the frequency of the high frequency current and is equipped with a frequency setting dial (not shown); , 12, is a transformer that controls the magnitude of the high-frequency current supplied to the heating coil 13. This transformer J2 is turned ON by a signal from the two-color temperature sensor 1 (not shown), and is activated by a limit switch described later. The relay switch (
(not shown) and a heating coil movement speed setting dial (not shown), and if the heating coil hyperactivity speed setting dial is set to a predetermined speed in advance, the relay switch is activated. When turned on, the heating coil 13 can be moved at the predetermined speed by moving forward in the direction of the arrow along the drawing direction of the tube 1 while being guided by the outside of the support 51).

6 is a hydraulic cylinder connected to the load device, and this hydraulic pressure '/
) 18 of the two-color thermometer (not shown)
The limit switch is turned on by the number and will be described later]6
It has a relay switch (not shown) that is set to 0 1j''F by a signal from the hydraulic pressure setting dial (not shown).

16i2, When the heating coil 13 finishes heating up to the end of the thickening/jlJ section, the transformer 12 comes into contact with it and closes, serving as a limit switch that generates a signal.

The signal from limit switch 16 is transmitted to transformer 12
, the high-frequency oscillator i o , and the hydraulic/cylinder 6 relay switch, the tow/slot 12 stops, the hydraulic cylinder 6 stops driving, and the high-frequency oscillator 10 starts generating high-frequency current. stop.

Next, the operation of the two sets of pipe material thickening processing apparatuses will be explained.

Spindle 7 of hydraulic cylinder 6.
12 is moved backward. The tube material 1 to be thickened is passed through the heating coil 13, one end of which is inserted into the positioning hole t$4a of the press bed 4, and the other end is inserted into the sabot treatment by advancing the spindle 7 in the direction of the arrow. Fix with tool 8. Until the heating coil 13 reaches one end of the thickened part of the pipe 1,
Move the transformer 12 forward in the direction of the arrow.

A two-color thermometer (not shown) of the heating coil 13 is set to a predetermined temperature. Set the frequency of the high-frequency current using the frequency setting dial (not shown) of the frequency controller 11. (described by columns). The heating coil moving speed setting dial (not shown) of the transformer 12 controls the moving speed of the heating coil, and the hydraulic pressure setting dial (not shown) of the hydraulic cylinder 6 controls the hydraulic pressure/
Set the oil pressure of each cylinder in advance.

When the high frequency oscillator 10 is turned on and the temperature of the heating section of the control 1 reaches the predetermined temperature, a signal is emitted from the transmitting section of the two-color thermometer (not shown). It is received by a relay switch (not shown) of the hydraulic cylinder 6 and a drive raceway (not shown) of the transformer 12. Then, the oil pressure 7 cylinder 6 is turned on, and the oil supplied from the oil pressure generator 9 pushes out the spindle 7 with a constant pressure of the preset +XL, thereby compressing the pipe 1 in the axial direction with a constant compression force. Compressed. On the other hand, transformer 12 (7)
'The J-shire switch is also turned ON, and the transformer moves in the direction of the arrow at a preset moving speed, continuing to heat the pipe material 1 at the predetermined temperature of the previous day. The heating width at this time is approximately 2 of the plate thickness.
The amount of water injected from the injection port 13a of the heating coil 13 is adjusted so that the deformation area of the tube material 1 is narrowed so that the amount of water is less than twice that.

When the transformer 12 moves forward in the direction of the arrow and the heating coil 13 finishes heating the other end of the thickened part of the pipe material 1, the transformer 12 contacts the limit switch 16, causing the transformer 12 to move and the hydraulic cylinder 6 to move. The drive is stopped, the high frequency oscillator 10 stops generating high frequency current, and the Ju material 1
Finished thickening process.

Thereafter, after the sowing material 1 has cooled down, the supply of cooling water 14 is stopped, and the slag control 1 is taken out.

Next, a specific example will be described.

Outer diameter 2161nmφ, plate thickness 8.6 +I1 related to Kangetsu 1
．． I11, a carbon steel pipe with a length of 5.5 m, a length of 500 m
A case will be described in which the thickness is increased/111 times over 31 mm at a thickness increase rate of 31%.

The conditions for the high frequency 1f conductive heating by the heating coil 13 are a frequency of 9kI-1,2, an output of 85K, W, and a heating temperature of 850C. The hydraulic pressure setting of the hydraulic cylinder 6 was set to 53.8 K7/cut (the cylinder diameter is 30 cnl and a compressive force of 38 tons can be produced from b).

In setting the frequency of the high-frequency current in the above-mentioned high-frequency induction heating, a preliminary experiment as shown in FIG. 3 was conducted.

Figure 3 shows that when the moving speed of the heating coil is constant,
FIG. 3 is a diagram showing an example of the relationship between the frequency ratio of the high-frequency current in high-frequency 1-contaminated conduction heating and the inner/outer diameter distribution ratio of the increased thickness; FIG.

In FIG. 3, 17 is the high frequency 1 when the hyperactivity speed of the sword mouth heating coil 13 is 1 ham / 117.
．． This figure shows the relationship between the frequency of high-frequency current in gas conduction heating and the inner/outer diameter distribution ratio of thickness increase.

In general, in high-frequency induction heating, as the frequency increases, the penetration depth of the high-frequency current becomes shallower, and the surface layer of the heated object is more likely to be heated, creating a temperature gradient where the surface layer becomes hotter.

By utilizing this cylinder circumference dJ and the characteristics of the proverbial induction heating,
When the circumference 1 ratio is increased, the temperature near the outer diameter surface of the tube material 1 increases, the deformation resistance of that part decreases, and the swaging force]1
The liquid formation by the process is done first in the vicinity of the outer casing surface. However, as is clear from Fig. 3, as the frequency of the high-frequency current increases, the distribution ratio of the amount of eyebrow meat increases.

For example, in order to ensure that the amount of increase in thickness on the inner diameter side is within the tolerance range of plate thickness dimensions according to JIS, the distribution ratio of the amount of increase in thickness between the inner and outer surfaces may be about 5. The frequency equation corresponding to the inner/outer surface distribution ratio of 5 for this increase in thickness is 9k 11y, so 9kH2 was set.

When the above-mentioned conditions were set and the thickness increasing process of the carbon steel pipe was carried out using the thickness increasing process apparatus according to FIG. 2, the desired thickness increase was achieved. Achieving a meat distribution ratio of 5, it was possible to make a 71-piece cutter with irregularities and no stripes.

FIG. 4 is a perspective view showing an example of the pipe material that has been thickened using the "d-thickness horn 11 machine" of the pipe material shown in FIG. 2, and FIG. FIG. 3 is an enlarged cross-sectional view showing details around the part.

In the figure, 18 is the thickened part of the pipe material 1, 18a is the thickened part on the outer diameter side, and 18b is the thickened part on the inner diameter side. ) is uniform and there is no irregular deformation at all, and the amount of increase in thickness of the internal pressure of 1t411'\ is still small (distribution ratio of inside and outside diameter of amount of increase in thickness -5).

The embodiments described above have the following effects.

(1) It is possible to achieve uniform thickening processing without distortions such as wrinkles and buckling, and to reduce the amount of thickening on the inner diameter side.
A method and apparatus for increasing the thickness of d material can be provided.

(2) According to the pipe material thickening processing method of this example, government regulation 1
It is possible to uniformly thicken any part of the
Secondary work (for example, bending work,
When carrying out ring processing, tube expansion horn processing, etc.), if this secondary processing part is subjected to 1D wall processing in advance, the reduction in plate thickness due to plastic deformation can be reduced in appearance. Therefore, there is no need to use thick walls, so the material cost is reduced by 10%.
~20% reduction.

゛Also, in the case of this book, Ka J? In the coil 13,
Since the injection port 13a for injecting the cooling water 14 is provided, there is an advantage that the heating width can be controlled by adjusting the amount of water injected from this injection port.

Note that even if the injection port is not provided, that is, even if the injection port is not used, there is little risk of irregular deformation of the dog soil and g material 1.

Furthermore, Honji 7A! In 11yu, the hydraulic cylinder 6 is used as a loading device for the pipe material 1, but even if a mechanical screw press or the like is used instead of the hydraulic cylinder 6, the same effect as in this embodiment can be obtained. be.

In this example, the outer diameter is 216 wnφ and the plate thickness is 8.
When increasing the thickness of a 6 mm carbon steel pipe to a J pipe thickness ratio of 31'>o and a J pipe thickness distribution ratio of 5 to 5, use a high frequency current of 1 Z to 9. However, it varies depending on the frequency +- of Shang Zhou's turtle style, the dimensions of the aggregate to be machined (outer diameter and plate thickness), the wall thickness ratio, and the external distribution ratio of Ruki. However, in short, any material that can provide a temperature gradient to the outsourced part such that the surface temperature of the material becomes the same as that of the original material is sufficient.

〔Effect of the invention〕

As explained in the seven songs above, according to the present invention, uniformly ground meat without aging deformities such as wrinkles and buckling can be produced.
In addition, it is possible to provide a method and a thickening processing apparatus for J-thickness processing of a blank material, which can reduce the amount of heat applied to the inner wall.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the thickness increased by the conventional 7JIJ method, and Fig. 2 is an actual measurement of the 7JIJ method for increasing the thickness of material according to an embodiment of the invention. An example of the JII machine for increasing the thickness of pipe materials, which is used for
Partial cross section lJf]1Δ, which also shows the pipe material to be removed:
Figure 3 i15 shows an example of the relationship between the frequency of high-frequency current in N-conductor m heating and the inner/outer diameter distribution ratio of thickening i when the moving speed of the heating coil is constant. The relationship between frequency and inner/outer diameter distribution ratio of increased thickness, Figure 4 is
Figure 5 is a perspective view showing an example of a pipe material that has been machined by the J gastric horn 11 machine using the thickening force machine 11 machine of the pig moon according to the figure. It is an enlarged sectional view showing reputation. l... Yoizuki, 6... Hydraulic cylinder, 10... High frequency oscillator, 11... Frequency controller, 13... Heating coil, 13a... Injection port, 14... Cold- AJ water, 1
8...Thickening egg part, 18a...External pressure 1111 thickening part, 181)...Inner diameter side thickening part. Agent: Patent attorney Kosaku Fukuda゛,゛' 1 (Igu or 1 person) Sheep / Kosaku. 2nd prisoner//10 Kaya 3 Zunotori Rōkazu (KHir)

Claims (1)

[Claims] 1. The parts of the control to be thickened are successively locally processed so that the surface layer of the previous month becomes high in temperature and gives a temperature gradient to the inner and outer diameter parts of the elongated material. A method for increasing the thickness of a pipe material, the method comprising increasing the thickness of the part to be increased in thickness by performing swaging processing by applying a compressive force in the axial direction of the pipe material while performing high-frequency induction heating. 2. A loading device capable of compressing the previous month in the axial direction;
an annular heating coil that is disposed on the outer periphery of the tube and movable along the axial direction of the tube; a high-frequency oscillator that generates a high-frequency current to be supplied to the heating coil; A pipe material thickening processing apparatus patented as comprising a frequency controller capable of controlling the frequency of the high-frequency current. A pipe material thickening processing apparatus according to claim 2, which is provided.