JPS6338077Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is a welding method for welding the welded end faces of metal pipes used to transport gas, oil, water, etc. from discharge areas, water sources, etc. to refining areas, consumption areas, etc. The present invention relates to a welding end face protection device for metal tubes, which allows metal pipes to be welded without causing damage or deformation to the welded end faces when they are connected.

BACKGROUND ART When welding and installing metal pipes, usually the long metal pipes are connected by sequentially welding the single pieces at the site. However, if the welded end surface of a single metal tube is damaged or the tube diameter is deformed when transporting the metal tube from the manufacturing factory to the site, it becomes impossible to perform accurate and reliable welding, and it becomes necessary to modify the welding surface at the site. is almost impossible and may cause disasters such as gas leaks, fluid leaks, or leaks. Furthermore, if the pipe is subjected to vibration after welding, there is a risk that the metal pipe will break at the welded part.

Conventionally, a structure was known in which a wooden frame assembled in a cross pattern was fitted into the inner periphery of the opening at both ends of a single metal tube, and the wooden frames at both ends were tied with wire to prevent the wooden frames from protruding outward. It is being However, since the work of connecting the wooden frames at both ends with wires must be done inside the metal tube, the installation work is time consuming and difficult, and requires labor.

Problems to be solved by the invention The purpose of the invention is to mechanically weld the welded end surface of a metal tube.
In addition to chemically protecting the welded end faces of metal pipes of different diameters with a protective device of the same shape, it does not cause distortion to the inner diameter of the metal pipe, and is low cost.
An object of the present invention is to provide a welding end face protection device for metal tubes that is robust and easy to manufacture.

Means for Solving the Problems The present invention has an L-shaped rising edge that comes into contact with the welded end surface of the metal tube, a rising edge that comes into contact with the inner circumferential surface of the metal tube, and a horizontal edge that touches the inner circumferential surface of the metal tube. A protective ring is formed by bending and cutting off a part to form a notch, and a protective ring is made of a polymeric piece extending to the rising edge on one side of the notch, and a protective ring is formed on the inner circumferential surface of both sides of the notch of the protective ring, and the protective ring is attached to the notch. Sliding door-shaped grooves are formed on the inner circumferential surface of the ring at symmetrical positions in the diametrical direction and on the inner circumferential surface at positions almost perpendicular to the diametrical direction, and the metal tube deformation formed by these grooves is prevented. The wedge plate fitting space forms a wedge-shaped space that narrows from the side closer to the rising side of the protection ring to the side farther away, and the tightening plate provided on each of the horizontal sides and the center member can be adjusted to advance and retreat radially. It is equipped with a device that allows
This metal tube end weld protection device includes a wedge plate that is fitted and driven into the wedge-shaped space of the tightening plate.

Effect The present invention uses the above-mentioned solution means to transfer the welded surface of the metal pipe end from the metal pipe manufacturing factory to the warehouse or ship hold.
Furthermore, the welded end surface is reliably protected during transport to the metal pipe installation site, and deformation of the metal pipe end is prevented, making it possible to manufacture and adapt to large and small metal pipes.

Example In the drawings, reference numeral 1 is a single metal pipe made of steel pipe or the like, and in order to achieve the best welding, the end face of this metal pipe, that is, the welding surface 2, is finished by cutting to a uniform smooth surface. , In order to improve heat conduction and electricity conduction during welding, welding end surface 2
The outer periphery of the end of each metal tube 1 is cut obliquely on the outside to form a slope 3. Reference numeral 4 designates a protective ring made of an elastic and flexible metal plate, such as a band-shaped steel plate, in which a notch 5 is provided by cutting a part of the ring. One side edge of this protective ring is formed by bending a rising side 6 corresponding to the welded end surface 2 of the metal ring 1 and a horizontal side 7 contacting the inner peripheral surface 1a of the metal tube 1 into an L shape. In addition, one end of the rising side 6 in the notch 5 of the protective ring 4 is extended to form an overlapping side 8, which overlaps the inner peripheral surface 1a of the metal tube 1 with the outer peripheral surface of the horizontal side 7 of the protective ring 4, as described later. The outer circumferential surface of the protective ring 4 is brought into close contact with the inner circumferential surface 1a of the metal tube 1. This overlapping side 8 serves to protect the welded end surface 2 of the metal tube 1 by blocking the notch 5 of the protective ring 4, that is, the welded end surface 2 of the metal tube 1, even if there is a considerable difference in the inner diameter of each metal tube 1. 10 and 10' form sliding door-shaped grooves 11 and 12 on both sides of the notch 5 of the protective ring 4, and the fitting space of the wedge plate 9 formed by these grooves 11 and 12 fits into the protective ring 4. This is a tightening plate having a wedge-shaped space 14 that is formed to become narrower from the side closer to the rising side 6 to the side farther from it, and the wedge plate 9 of the metal pipe mouth deformation prevention member A is connected to the tightening plate 10. 10'
By fitting and driving the notches 5 into the wedge-shaped space 14 formed in , the interval between the notches 5 is widened, and the outer circumferential surface of the protective ring 4 is tightly adhered to the inner circumferential surface 1a connected to the welded end surface 2 of the metal tube 1. Tightening plates 1 provided on the inner peripheral surface of the protective ring 4 on both sides of the notch 5 of the protective ring 4
0 and 10', a sliding door-shaped groove 11a is provided on the inner circumferential surface of the notch 5 and the protective ring 4 at positions symmetrical in the diametrical direction, and on the inner circumferential surfaces at positions symmetrical in the direction substantially perpendicular to the diametrical direction. and 12a, 11b and 12
b, 11c and 12c, and these grooves 11a and 12a, 11b and 12b,
11c and 12c of the tube mouth deformation prevention member A are fitted into the wedge plates 9a, 9b, 9c so that the space that fits into the wedge plates 9a, 9b, 9c of the pipe mouth deformation prevention member A, which is formed by 11c and 12c, becomes narrower from the side closer to the rising side 6 of the protection ring 4 to the side farther from it. Formed wedge-shaped space 1
4a, 14b, 14c to tightening plates 10a and 10
a', 10b and 10b', 10c and 10c' respectively. Wedge plate 9 of pipe port deformation prevention member A,
To explain in more detail about 9a, 9b, and 9c, each wedge plate is bent to one side, and both side edges of the tip thereof are formed into a wedge shape. Each wedge plate 9,
Attach the ends of reciprocating members S, S ₁ , S ₂ , S ₃ such as screws to the mounting portions of 9a, 9b, and 9c so that they can rotate freely, and each retractable member S, S ₁ , S ₂ , S ₃ are attached to the female threaded portions 16 of the mounting plate 15 so as to be movable forward and backward. Reference numeral 17 indicates a deformed part for a wrench provided between each of the reciprocating members S, S ₁ , S ₂ , and S ₃ . wedge plate 9,
The tips of 9a, 9b, 9c are tightened by tightening plates 10 and 10',
10a and 10a', 10b and 10b', 10c and 10
The horizontal portion of the protective ring 4 is fitted into the wedge-shaped space 13 between the ends of the metal tube 1 from the outside from both ends of the metal tube 1, and by applying a wrench to the irregularly shaped portion 17 and rotating the reciprocating members S, S ₁ , S ₂ and S ₃ . The outer peripheral surface is brought into close contact with the inner peripheral surface of the metal tube to protect the welded surface of the metal tube 1 and to prevent the end of the metal tube 1 from deforming due to pressure applied to the metal tube 1 from the outside. To unpack the metal tube 1 protected in this way at the welding site, turn the irregularly shaped part 17 in the opposite direction with a spanner and tighten the clamping plates 10, 10a, 1.
0b, 10c and the wedge plates 9, 9a, 9b, 9c are released and the mounting plate 15 and the wedge plates 9, 9a, 9b,
9c from the protective ring 4, and attach the protective ring 4 to the metal tube 1.
Remove both ends outwards. In the embodiment described above, four screws were placed in a cross shape as a reciprocating member, and a wedge plate with each attached to the screws was configured to support the inner peripheral surface of the end of the metal tube. Depending on the situation, two or more screws can be used. Alternatively, instead of screws, turnbuckles, cams and levers, or other expansion members may be used to press and support the wedge plate of the metal pipe mouth deformation prevention member from the inside to the outside. Further, the entire outer peripheral surface of the protective ring is coated with polyester resin, and the welded end surface of the metal tube and the protective ring are bonded via the polyester resin.

Effects As described above, in the present invention, in order to insert and fix the wedge plate of the metal pipe mouth deformation prevention member into the wedge-shaped space formed by the tightening plate of the protective ring, the metal pipe mouth deformation prevention member It is possible to have both the adhesion to the pipe and the effect of preventing deformation of the pipe opening of the metal pipe, and each wedge plate can be extended outward or retracted inward using a reciprocating member such as a screw to prevent the metal pipe from deforming. The metal tube mouth deformation prevention member installed at both end openings of the metal tube can be expanded or contracted according to the inner diameter of the protective ring, and each wedge plate can be fitted and tightened into the inner diameter of the metal tube or the inner diameter of the protective ring. It is possible to omit the work of connecting two pieces with wires passed through the metal pipes, which speeds up the packing and unpacking work of metal pipes, and this pipe mouth deformation prevention member can be used repeatedly, saving resources. It is useful for In addition, by forming the cross section of the protective ring into an L-shape with a rising side and a horizontal side, and by extending one end of the rising side to form an overlapping piece, the horizontal side of the protective ring can be placed at the welding point of the metal pipe end. By fitting the protective ring into the inner circumferential surface and placing the rising edge of the protective ring against the welded end surface of the metal tube and opening the horizontal ends of the protective ring strongly to both sides with the notch as the border, the inner diameter of the protective ring expands and the outer circumferential surface It can be tightly tightened to the inner peripheral surface of the metal tube, and the overlapping edge of one end of the protective ring overlaps the outer peripheral surface of the rising edge of the other end of the protective ring, so that the welded end surface of the metal tube in the notch of the protective ring is exposed. Therefore, the entire welded end surface of metal tubes with slight differences in outer diameter can be reliably covered and protected. Moreover, there are excellent effects such as the protection ring does not come off from the metal tube during transportation when the metal tube is loaded onto a transport vehicle.

[Brief explanation of drawings]

Figure 1 is an exploded perspective view of the present invention, Figure 2 is a perspective view of the present invention seen from the opposite side of Figure 1, Figure 3 is an exploded perspective view of the tube mouth deformation prevention member, and Figure 4 is an exploded perspective view of the present invention. An explanatory view of the unfolded protection ring, FIG. 5 is a longitudinal sectional plan view of the present invention assembled to a metal tube, and FIG. 6 is an enlarged longitudinal sectional side view of the metal tube with a portion cut away to show welding locations. A: Metal pipe mouth deformation prevention member, 9, 9a, 9b,
9c: wedge plate, 10, 10', 10a, 10a', 1
0b, 10b', 10c, 10c': Tightening plate, S,
S ₁ , S ₂ , S ₃ : advancing/retracting member, 14, 14a, 14b,
14c: wedge-shaped space.

Claims (1)

[Scope of utility model registration request] Wedge plates 9, 9a, 9 of metal pipe port deformation prevention member A
b, 9c are respectively provided on reciprocating members S, S ₁ , S ₂ , S ₃ which are attached to the mounting plate 15 so as to move radially forward and backward, and wedge-shaped spaces 14 , 14 a, are provided on the inner peripheral surface of the protective ring 4 . Tightening plates 10 and 10', 10a and 10a', which are removably installed on 14b and 14c,
1. A metal tube end weld protection device, characterized in that it is fitted into 10b and 10b' and 10c and 10c'.