JPH08132283A - Production of pipe filled with powder and granular material - Google Patents

Abstract

PURPOSE: To obtain a process for producing a pipe filled with powder and granular materials having the filling rate of the powder and granular materials uniform over the entire length of the pipe and uniform quality with high efficiency and productivity. CONSTITUTION: The pipe is filled with the powder and granular materials under vibration conditions of <=200 in the difference between the product (K1 ×D1 ) of the mechanical index K1 of the max. diameter part of the pipe coil and the max. diameter D1 of the coil and the product (K2 ×D2 ) of the mechanical index K2 of the min. diameter part of the pipe coil and the min. diameter D2 of the coil given by the following equation I and II at the time of placing the pipe coil on a vibration table and supplying the powder and granular materials from the pipe end to fill the pipe with this materials by applying vibration thereon: K1 =a1 (2πf)<2> /g...(I), K2 =a2 (2πf)<2> /g...(II), where K1 : the mechanical index of the max. diameter part of the coil, K2 : the mechanical index of the min. diameter part of the coil, a1 : the horizontal amplitude (cm) of the max. diameter part of the coil, a2 : the horizontal amplitude (cm) of the min. diameter part of the coil, f: the vibration frequency (Hz), g: dynamic acceleration (980cm/sec<2> ).

Description

Detailed Description of the Invention

[0001]

This invention relates to carbon steel, high alloy steel,
The present invention relates to a method for manufacturing a flux-cored wire for welding, a wire containing an oxide superconducting material, and the like, in which powder particles are filled in a metal tube such as stainless steel, a copper alloy, an aluminum alloy or the like, and a powder particle-filled tube. Here, the powder or granule means a flux for welding, an oxide superconducting material, a powder of an additive material for steelmaking, a granule or a mixture of powder and granules.

[0002]

2. Description of the Related Art A flux-cored seamless wire for welding is one type of powder-filled tube. A method of filling the inside of the wire with flux in the process of manufacturing a flux-cored seamless wire for welding will be described with reference to FIG. In the figure, P is a steel pipe wound around a steel bobbin 1, 2 is a vibrating table equipped with a vibration motor for giving spiral vibration to the pipe via the bobbin 1, and 3 is a hopper for accommodating the flux F.

The pipe P wound on the bobbin 1 is placed on the vibrating table 2 so that the axis of the wound body is vertical, and the flux supply end of the pipe P is bent to the upper part of the bobbin 1 to bleed air. The flux F from the hopper 3 is supplied to the pipe P via the intermediate pipe 4 provided with the branch pipe 5 for. Further, a lid 6 for preventing flux leakage is provided at the end of the pipe P.

The flux F is supplied and filled in the pipe P by such an apparatus. After that, the diameter is reduced, and if necessary, annealed, then drawn to a desired diameter, and wound to obtain a product.

By the way, when the flux is filled by the above method, the flux is not filled uniformly over the entire length in the longitudinal direction of the pipe, and the density of the filled flux in the longitudinal direction, that is, the filling rate varies. More specifically, as shown in FIG. 2, the filling rate is low at the flux supply end, and tends to gradually increase as it approaches the pipe tip. This shows that there is a large difference in the amount of alloy in the flux, especially at both ends of the pipe, as shown in FIG. Also, the difference in filling rate at both ends of the pipe tends to increase as the pipe length increases. The target filling rate of the flux in FIGS. 2 and 3 is 14.5%, the amount of Ni in the flux is 15%, and the pipe length is 1000 m.

The flux-cored seamless wire for welding produced by filling the pipe with the flux in this way has a short pipe length, or even if the pipe length is long, the flux-cored seamless wire for general mild steel materials has good welding workability and workability. In some cases, both mechanical properties do not matter. However, when the length of the pipe is long, and in the case of a flux-cored seamless wire for welding, which contains an alloying element such as for low-temperature steel or high-strength steel, the alloy composition changes at the flux supply end and the pipe tip. Therefore, when welding is performed with the wire at the flux supply end and the pipe end, the difference in mechanical performance between the weld metals becomes large.

As a method for solving such a problem, there is a "method for manufacturing a flux-cored wire for welding" disclosed in Japanese Patent Laid-Open No. 61-144297, and there is a method for performing flux filling in a vacuum atmosphere. However, when the pipe length becomes long, a difference in filling rate occurs between the flux supply end and the pipe tip even in this method. In addition, Japanese Patent Laid-Open No. 6-1
In "Production method of powder-and-granule-filled tube" of JP06387A,
A method is disclosed in which two or more kinds of powder particles having different particle size configurations are divided into positions in the pipe longitudinal direction or filled while changing the mixing ratio. However, in this method, it is necessary to separately manufacture powders having different particle size configurations, which is a problem in terms of efficiency.

[0008]

Therefore, when manufacturing a flux-cored seamless wire for low-temperature steel or high-strength steel containing alloy elements for welding, a short pipe is filled with flux at the expense of productivity. I had no choice.

[0009] Therefore, an object of the present invention is to provide a method for producing a powder / granule-filled pipe which has a uniform powder / granule filling rate over the entire length of the pipe, is of good quality, and is highly efficient and highly productive.

[0010]

DISCLOSURE OF THE INVENTION The inventors of the present invention set a pipe winding body on a vibrating table, and when the powder and granules are filled from the pipe end while applying vibration, the pipe tip and the powder and granule supply It was found that the filling rate varies at the end, but the biggest cause of this is the difference in vibration conditions due to the position difference of the pipe winding body. Therefore, it has been found that in order to make the filling rate of the powder or granules in the pipe uniform, it is sufficient to fill the powder or granules by reducing the vibration condition difference between the respective positions of the pipe winding body.

The present invention has been made on the basis of the above findings. When the pipe winding body is placed on a vibrating table and vibration is applied to supply and fill the powdery particles from the end of the pipe, the following formulas 1 and 2 are used. The product (K ₁ × D ₁ ) of the machine index K _{1 of the} maximum diameter part of the wound body and the maximum diameter D ₁ of the wound body, and the machine index K ₂ of the minimum diameter part of the wound body and the minimum diameter D of the wound body Product of ₂ (K ₂ × D
It is characterized in that the powder and granules are filled under a vibration condition in which the difference from ₂ ) is 200 or less. K ₁ = a ₁ (2πf) ² / g (1) K ₂ = a ₂ (2πf) ² / g (2) where K _{1 is} the machine index of the maximum diameter part of the wound body K ₂ Machine of the minimum diameter part of the wound body Index a ₁ Horizontal amplitude of the largest diameter part of the wound body (cm) a ₂ Horizontal amplitude of the smallest diameter part of the wound body (cm) f Frequency (Hz) g Dynamic acceleration (980 cm / sec ² )

The diameter of the wound body is equal to the outer diameter of the bobbin or winding cylinder wound with the pipe, plus twice the thickness of the pipe winding layer. The lower limit of the difference between K ₁ × D ₁ and K ₂ × D ₂ is 0. As is clear from the above definition, when one layer of the pipe is wound on the bobbin, K ₁ × D ₁ and K ₂
The difference from × D ₂ becomes zero. In the process of manufacturing powder-filled tubes,
If the difference between K ₁ × D ₁ and K ₂ × D ₂ exceeds 200,
For example, the number of winding layers of the pipe is reduced to 200 or less.

[0013]

[Function] By reducing the difference in the vibration condition between the respective positions of the pipe winding body, the packing rate of the powder and granules becomes uniform. The largest difference in vibration condition is between the maximum diameter part and the minimum diameter part outside the pipe winding body, and the difference in vibration conditions in this part is reduced. That is, the product (K ₁ × D) of the machine indexes K ₁ and K _{2 of the} outermost diameter portion and the innermost diameter portion of the pipe winding body and their respective diameters D ₁ and D _2.
By setting the difference of ( ₁ , K ₂ × D ₂ ) to 200 or less, the packing rate of the powder and granules becomes uniform in the longitudinal direction of the pipe. This is 200
When it exceeds, the difference in the vibration conditions due to the difference in the position of the pipe wound body becomes large, and the powdery or granular material filling rate becomes uneven in the longitudinal direction of the pipe, resulting in variations. For example, the variation of the powder / granular filling rate exceeds ± 0.5%.

[0014]

EXAMPLE A method for manufacturing a flux-cored seamless wire for welding will be described below as an example. First, the flux of the raw material mixing ratio of the low temperature steel wire shown in Table 1 was mixed and granulated with water glass.

[Table 1]

The flux shown in Table 1 was filled into the pipe under the various conditions shown in Table 2 using the apparatus shown in FIG. The target filling rates were all set to 14.5%.

[0016]

[Table 2]

The pipe is made of mild steel and has a diameter of 11 mm and a wall thickness of 2.1.
mm and length of 1000 m were wound on bobbins with different shapes (bobbin winding diameter). The flux filling rate and the amount of Ni were measured at three points of the pipe supply part, the center part, and the pipe tip part of the wire of each test example, which was an intermediate product having a diameter reduced to 3.2 mm after flux filling. The results are shown in Table 3. The Ni content in Table 3 is a weight ratio with respect to the Ni content in the flux-filled tube, that is, the weight of the mild steel pipe.

[Table 3]

As a result, Nos. 1 to 3 of the present invention are K
The difference between ₁ × D ₁ and K ₂ × D ₂ is 200 or less, that is, the difference in vibration conditions between the maximum diameter portion and the minimum diameter portion is small, so the flux target filling rate of 14.5% ± 0.2% is obtained. The amount of Ni also showed very little variation and was extremely satisfactory.

Comparative examples Nos. 4 to 6 are all K ₁ ×
Since the difference between D ₁ and K ₂ × D ₂ exceeds 200, that is, the vibration condition difference between the maximum diameter portion and the minimum diameter portion is large, the flux target filling rate is 14.5% ± 1.3%, and Ni The amount of variation is very large.

[0020]

According to the present invention, it is possible to make the filling rate of the powder and granules uniform over the entire length of the pipe. As a result, the quality of the powder / granule-filled pipe is good, the length of the pipe can be increased, and the productivity is improved with high efficiency.

[Brief description of drawings]

FIG. 1 is a side view of a flux filling device.

FIG. 2 is a graph showing the results of measuring the filling rate after flux filling.

3 is a graph showing the Ni analysis result of the wire of FIG.

[Explanation of symbols]

 1 Bobbin 2 Shaking Table 3 Hopper 4 Intermediate Pipe 5 Branch Pipe 6 Lid F Flux P Pipe

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Fumio Hayashi 7-6-1, Higashi Narashino, Narashino, Chiba Prefecture Narashino Factory of Nittetsu Welding Co., Ltd. (72) Satoru Ando 7-6, Higashi Narashino, Narashino, Chiba Prefecture No. 1 Narashino Factory of Nittetsu Welding Co., Ltd.

Claims (1)

[Claims] 1. A mechanical index of the maximum diameter part of the winding body given by the following formulas 1 and 2 when the winding body of the pipe is placed on a vibrating table and the powder particles are supplied and filled from the end of the pipe under vibration. The product of K ₁ and the maximum diameter D ₁ of the wound body (K ₁ × D ₁ ) and the product of the machine index K ₂ of the minimum diameter portion of the wound body and the minimum diameter D ₂ of the wound body (K 1
₂ × D ₂ ) The method for producing a powder / granule-filled tube, which comprises filling the powder / granular material under a vibration condition having a difference of 200 or less. K ₁ = a ₁ (2πf) ² / g (1) K ₂ = a ₂ (2πf) ² / g (2) where K _{1 is} the machine index of the maximum diameter part of the wound body K ₂ Machine of the minimum diameter part of the wound body Index a ₁ Horizontal amplitude of the largest diameter part of the wound body (cm) a ₂ Horizontal amplitude of the smallest diameter part of the wound body (cm) f Frequency (Hz) g Dynamic acceleration (980 cm / sec ² )