JPH0575488B2 - - Google Patents

Description

[Detailed Description of the Invention] A. Industrial Application Field The present invention relates to a continuous pipe manufacturing method for non-ferrous metal pipes.
In particular, the present invention relates to a continuous pipe-making method in which reduction is performed while pinch conveying the pipe-making tube.

B. Summary of the Invention The present invention aims to prevent deformation and buckling of the tube due to various causes, as well as breakage and elongation due to tensile force, in the post-annealing process performed on the tube manufacturing tube in continuous pipe manufacturing equipment for non-ferrous metal pipes. The present invention aims to provide a continuous pipe manufacturing method that prevents the above-mentioned problems, and a pinch section having a plurality of rows of assembled rolls made of a rigid material is provided between the annealer section and the winder, and the assembled rolls of the pinch section are By pinching and transporting the tube, we perform a reduction process on the tube to reduce its diameter by 10 to 30%, allowing smooth transport of tubes that are easily deformed or cut due to their softening. At the same time, it is rolled up into a finished product having predetermined accurate dimensions and shape.

C. Conventional technology ERW pipe welding technology involves continuous cold roll forming of a strip-shaped coil plate material to form a tube shape with slit-like joints in the length direction.Electric power is applied to both edges of the seam. In recent years, it has been widely used as a method for electric resistance welding by supplying and heating radiators, and its applications range from welding extremely thin plates such as radiators to thick plates several tens of millimeters thick, as well as for welding materials such as iron and stainless steel. In addition to alloys, it is also applied to non-ferrous metals such as copper and aluminum.

What is shown in FIG. 3 is a general configuration diagram of a non-ferrous metal electric resistance welded pipe welding pipe manufacturing equipment equipped with a pipe winding section. The outline will be explained with reference to FIG.

Non-ferrous metal ERW pipe welding pipe manufacturing equipment (hereinafter referred to as pipe manufacturing equipment) includes a hoop cage section 2 that facilitates the supply of the pipe material 1a, a forming section 3 that gradually forms the material into a tubular shape, and a squeeze roll 5. A welding section 4 performs electrical resistance welding while press-welding, an annealing section 6 that improves the structure and mechanical properties of the welded section, and enables winding processing in the post-process, and a winding machine for the annealed tube. The tube is generally composed of a pinch mechanism 102 for transporting the tube, a cutter 8 for cutting the tube as necessary, and a winding section 9 equipped with a winding drum for winding up the tube.

Pipe manufacturing in the pipe manufacturing equipment configured as described above is performed through the following steps. The pipe-making plate material 1a, which is generally supplied in a band-shaped coil, is supplied to the forming section 3 with a margin of material supply provided by the hoop cage 2, and is shaped into a flat plate by the forming rolls of the forming section 3. It is gradually formed into a tubular shape and then supplied to the welding section 4. In the weld part 4, a material 1a formed into a tubular shape having a slit-like seam in the length direction is used.
The edges of the joints are pressed against each other by a squeeze roll 5 and heated by electrical resistance to be welded into a tube shape and sent to an annealer section 6. The tube 1b before entering the annealer section 6 is not soft enough to be wound onto a winding drum in the winding section, and therefore generally cannot be wound up as is. Therefore, in order to wind it onto a drum, it is necessary to perform an annealing treatment (annealing) in the annealer section 6 to sufficiently soften it. The annealed tube 1b is delivered to the pinch mechanism 102. The pinch mechanism 102 pinches and conveys tubes using a belt made of rubber or the like, cuts defective tubes with a cutter 8 immediately after the start of operation, and transfers subsequent good tubes to the winding drum of the winding section 9. Wind it up.

As mentioned above, the pipe manufacturing equipment that welds tubes using the ERW pipe welding method aims to provide products with stable quality through the simple configuration of the manufacturing line and high productivity. Ta.

D. Problems to be Solved by the Invention However, in the above-mentioned conventional pipe manufacturing equipment for non-ferrous metal pipes, the process after annealing the welded tube in the annealer section 6 involves There were factors that made it unstable.

The tube annealed in the annealer section 6 is in a softened state due to heating, but
In this state, if various external shocks occur, or if there is a discrepancy in the conveying speed between the inlet and outlet sides of the pipe-making line, or if the speed fluctuates, the tube may be buckled due to tube conveyance clogging, or Cutting or elongation of the tube occurs due to the tube's tensile phenomenon. The above-mentioned phenomenon often occurs particularly when the pipe-making equipment is configured such that the pinch mechanism 102 is not disposed on the outlet side of the annealing section 6.

In addition, if the configuration of the pinch mechanism 102 in pipe manufacturing equipment equipped with the pinch mechanism 102 is of a frictional force retention type, an elastic belt made of rubber or the like is used to prevent buckling or cutting of the tube. The tube is pinched by the belt and the softened tube is conveyed by the frictional force between the belt and the tube, but the frictional force also changes depending on the magnitude of the contact pressure with the tube. For this reason, the pinch mechanism has a function of adjusting the pressure with which the pinching belt contacts the tube, and adjusts the contact pressure when the tube is conveyed to an appropriate value.

However, since the semicircular caliber formed on the belt of the pinch mechanism shown in FIG. 4a is constant and the belt is an elastic body, if the gap between the belts changes depending on the pressing force, As shown in Figure 4b, the gap becomes large and it becomes impossible to obtain enough frictional force to perform a reliable pinch.
As shown in Figure c, when the gap becomes smaller, it crushes the tube and also deforms the caliber, causing the tube to become elliptical.

Since the tube to be transported is softened and easily deformed, in order to avoid changes in the cross-sectional shape of the tube, the pressure must be less than the normal gap shown in Figure 4a.
In this case, the frictional force tends to be insufficient. On the other hand, in order to prevent the tube from buckling, stretching, or breaking during transportation, it is necessary to pinch and convey it with sufficient frictional force, and to do this, the pressure applied by the belt must be increased. As a result, the gap between the belts becomes smaller, making it difficult to prevent tube deformation. In addition, in such a pinch mechanism, slips are likely to occur between the tube 1b and the belt, so it is necessary to accurately control the conveying speed of the tube 1b in the pinch mechanism, and to adjust the conveying speed of the tube 1b in the pre-processing mechanism and the post-processing mechanism. There were also difficulties in achieving accurate synchronization.

The present invention was created in view of the above-mentioned problems, and provides a continuous tube manufacturing method that allows annealed tube manufacturing tubes to be conveyed to a winder using a pinch mechanism that does not cause deformation or elongation. For the purpose of providing.

E Means for Solving the Problems The present invention manages the deformation that is likely to occur in the tube formed by the pinch mechanism, and reduces the diameter of the tube using rolls using a reducing method, thereby ensuring that the tube is captured securely. The tube is pinched and conveyed to a winder, and then formed into a predetermined tube diameter.The specific means used is to have multiple rows of reduction rolls made of a rigid material between the annealer section and the winder. A pinch part is provided, and while the pinch part pinches the tube and conveys it, the tube has a diameter of 10 mm.
This method uses a continuous pipe manufacturing method for non-ferrous metal pipes, which is characterized by performing a reduction process with a reduction rate of 30%.

F Effect By using the above-mentioned means, the annealed tube is reliably pinched by a plurality of rows of reduction set rolls provided at the pinch section and conveyed to the winding machine, while the above-mentioned rigid material roll The tube diameter is gradually reduced through reduction processing and molded to the specified dimensions.
It is wound up by a winding machine.

G. Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the main components of a non-ferrous metal pipe manufacturing equipment according to an embodiment of the present invention, and the same components as in FIG. Detailed explanation will be omitted. First, the configuration of this embodiment will be explained. In the configuration of the pipe manufacturing equipment shown in FIG. 1, the hoop cage section and forming section, which are the processing mechanisms for the temporary material 1a to be pipe-formed up to the welding section 4, are not directly related to the configuration of this embodiment. It is omitted. As shown in FIG. 1, this embodiment includes a welder section 4 that performs high-frequency electrical resistance welding of the plate material transferred from the previous process and formed into a tubular shape, and an annealer section 6 that is a pretreatment mechanism that performs annealing treatment on the welded tube.
, a pinch section 7 that pinches and transports the tube softened by annealing treatment, and a winding section 9 that is a post-processing mechanism that winds up the transported tube onto a winding drum. The pinch section 7, which is a main part of the configuration of the present invention, will be explained in detail.

FIG. 2a shows the configuration of the pinch section 7 that performs reduction, and is constructed by arranging a plurality of set rolls in a row on a pipe-making line. Each roll 7a, 7b,...7f is placed on both sides of the tube 1b.
Although the lower rolls are arranged in one set, only the upper rolls are shown in FIG. 2a, and the lower rolls are omitted. In this example, there are 5 rolls in a row.
The rollers are arranged in pairs, and the rolls are made of a rigid material made of steel. Five sets of rolls 7a, 7b, 7 arranged in a row on this pipe-making line
c, 7e, and 7f are formed with circular calibers having different diameters for each set, as shown in FIG. 2b. That is, as shown in FIG. 3, a pinch mechanism 102 is provided after the annealer section 6, and as shown in FIG.
As shown in b, the roll set 7a, which is the upstream end of the pinch section 7 that first pinches the tube 1b with an outer diameter D ₀ conveyed from the annealer section 6, sets its circular caliber to a radius of R ₁ for each roll. The set of rolls 7b forms each roll with a caliber radius of _R2 , and the set of rolls 7c sequentially forms each roll with a caliber radius _{of R3.}
The roll set 7e has a caliber radius of _R4 , and the roll set 7f, which is the downstream end of the pinch section 7, has a caliber radius of _R5 . At this time, 5
The arrangement of the caliber radius of the set of row-like rolls is
They are formed so that R ₁ > R ₂ > R ₃ > R ₄ > R ₅ .

Various experiments were conducted to determine the range of reduction to be performed by the five sets of rolls, and as a result, the range of reduction to be performed by pinch section 7 was approximately 10 to 30% reduced in diameter of tube 1b. It has been found that it is suitable to configure the pinch portion 7 so that the ratio is small. That is, if the reduction rate due to reduction is less than 10% of the diameter of the tube 1b, the pinch portion 7 will not be able to capture the tube 1b sufficiently, and if it exceeds 30%, the tube 1b will be hardened due to work and cannot be wound. It was inappropriate to do so. In addition, in order to perform smooth reduction processing,
The number of rows of rolls to be arranged must be at least 5 or more, and the difference in caliber diameter between the set rolls is
The upper limit is preferably 0.5m/m.

The pipe-making method in this embodiment configured as described above will be explained in detail using FIGS. 2a and 2b. In the conveyance direction shown by the arrow in _FIG . Roll 7a is a caliber formed into a circular shape with a diameter of 2R _{1 and} tube 1.
b is captured and rotated, and the tip of the tube 1b is surely pinch-transferred so that the diameter of the second row set of rolls 7b is adjusted.
Send it to the caliber of 2R ₂ . This time group roll 7
The diameter of caliber a is 2R ₁ and the diameter of tube 1b
Since the diameter is at most 0.5 m/m smaller than D ₀ , the diameter of the tube 1b that has passed through the set of rolls 7a is reduced to D ₁ (D ₀ >D ₁ ), that is, D ₁ =2R ₁ . Tube 1b with diameter reduced to D ₁
While being pinch conveyed by set rolls 7b, it is reduced to a diameter of D ₂ =2R ₂ by a caliber formed to have a diameter of 2R ₂ which is at most 0.5 m/m smaller than the diameter D ₁ . Similarly, the diameter of the tube 1b is reduced to D ₃ =2R ₃ while being conveyed through the set roll 7c in a pinch, and the diameter D ₅ =2R ₅ of the tube 1b that has passed through the final set roll 7f is conveyed to the pinch section 7. This results in a reduction of about 10 to 30% compared to the diameter D ₀ at the time of reduction.

Therefore, once the diameter _D5 of the tube required as a finished product is determined, the number of rows of reduction rolls provided at the pinch section and the reduction width between the rolls can be set to determine the size of the welded tube to be annealed. The diameter D ₀ is easily calculated. For example, if the product tube diameter D ₅ is set to 10 m/m, and the number of rows of assembled rolls is set to 5, the reduced dimension width between the assembled rolls is set to the maximum.
By setting 0.5m/m, D ₀ =0.5×5+
10 = 12.5 m/m, and the welded tube to be carried into the pinch section 7 has a diameter of 12.5 m/m.
In addition, since the desirable overall reduction rate is 10 to 30%, if the minimum reduction rate is 10% for the finished tube diameter D ₅ = 10 m/m, the tube manufacturing tube diameter D ₀ = 11 m/m. Therefore, it can be seen that when the number of rows of set rolls for reduction is 5, it is suitable to select D ₀ =11 to 12.5 m/m.

Unlike the conventional pinch section using a belt, which is caused by frictional force, the pinch section 7 has tube 1
Since it captures b reliably and does not cause slips,
The transport speed of the tube 1b in the pinch section 7 is
It is determined by the rotational speed of the set of rolls for reduction and can be precisely controlled. Therefore, the conveyance speed of the tube 1b at the upstream end of the pinch section 7 is synchronized with the conveyance speed in the annealer section, which is a pretreatment mechanism, or the tube 1b is controlled so as to have a slight constant tension (pulling force) applied thereto. On the other hand, the winding section 9
The conveying speed of the tube 1b from the pinch section 7 to the post-processing mechanism, such as the winding speed of the winding drum, is synchronized with the conveying speed of the tube 1b at the downstream end of the pinch section 7, or a light constant tension is applied to the tube 1b. It is easy to control the drive to work.

By performing such speed control, the tube 1b that has been softened by the annealing treatment is not subjected to excessive tensile force or buckling, and smooth conveyance and winding are possible. Further, by reduction processing at the pinch portion 7, the tube 1b can be formed into a predetermined external size and shape. Note that the method of synchronizing the transport speed of the tube 1b in each part and controlling the constant tension drive is the method of controlling the rotational speed of the roll and winding drum of each part,
Alternatively, any general method may be used, such as a method of controlling the rotational torque within a certain range while detecting it.

H. Effects of the Invention As explained above, the present invention provides a pinch section having a plurality of rows of set rolls made of a rigid material between the annealer section and the winding machine of non-ferrous metal pipe welding pipe manufacturing equipment, and the pinch section By performing a reduction process on the tube to reduce its diameter by 10 to 30% while pinching and conveying the tube, the tube is reliably captured by the rolls.
Since the rolls are set to the required diameter and then subjected to reduction processing, they are accurately formed to the set diameter and cross-sectional shape.

Furthermore, the tube transport speed at the upstream end of the pinch section is synchronized with the tube transport speed in the pre-processing mechanism, or the drive is controlled so that a constant tension is applied, and the tube transport speed in the post-processing mechanism is controlled. It is easy to perform drive control to stably wind the tube onto the drum in synchronization with the transport speed of the tube at the downstream end of the section or with a constant winding torque. Therefore, by stably transporting the tube by establishing synchronous speed control or constant tension control through the pre- and post-processing mechanisms, deformation, elongation, and
Buckling etc. are eliminated.

[Brief explanation of drawings]

FIG. 1 shows the main components of a pipe-making equipment according to an embodiment of the present invention, and FIGS. 2a and 2b show the construction of the pinch section. 3 and 4 show an embodiment according to the prior art. 1a... Plate material, 1b... Tube, 7... Pinch part, 7a, 7b, 7c, 7e, 7f... Roll, 9... Winding part, D ₀ ... Diameter of welded tube, D ₁ , D ₂ , D ₃ , D ₄ , D ₅ ... Diameter of the reduced tube, R ₁ , R ₂ , R ₃ ,
R ₄ , R ₅ ... Roll caliber radius.

Claims (1)

[Scope of Claims] 1. A continuous non-ferrous metal pipe that is manufactured by a non-ferrous metal pipe welding pipe manufacturing equipment, is annealed in an annealer unit that is a pre-processing mechanism, and then wound in-line by a winder that is a post-processing mechanism. In the tube manufacturing method, a pinch section including a plurality of rows of set rolls made of a rigid material is provided between the annealer section and the winder, and while the pinch section pinches and conveys the tube, the diameter of the tube is fixed to the tube. By performing a reduction process with a reduction ratio of 10 to 30% of The conveying speed of the tube in the post-processing mechanism is synchronized with the conveying speed of the tube at the downstream end of the pinch section, or is controlled to a slightly faster speed at which a light tensile force is applied to the tube. 1. A method for continuous production of non-ferrous metal pipes, characterized in that the speed is synchronized with the conveyance speed or controlled to a slightly faster speed to the extent that a light tensile force is applied to the tube.