JPH11291081A - Welded flange - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent zinc from being boiled or vaporized during the welding with a steel tube by forming a circular seat concentric with forward and rear surfaces of a hole in a galvanized steel member to be welded, and continuously providing first and second seats to have the outside diameter of the specified dimensions added to the specified depth and the specified hole diameter on one surface, and the specified dimensions added to the specified depth and hole diameter on the other surface. SOLUTION: A flange 1 having a hole 4 in which a tube is inserted is immersed in a molten zinc to be galvanized. A seat 5 is formed on a forward surface 3, and seats 6, 7 are formed on a rear surface 2, and the seats 5, 6, 7 are cut to remove a zinc film. The depth of the seat 5 is selected from 3-9 mm, and the outside diameter is the one obtd. by adding the length selected from the range of 0.5-3 mm to the inside diameter of the flange. The depth of the seat 7 is selected from the range of 0.5-3 mm and the outside diameter is the one obtd. by adding the length selected from the range of 5-10 mm to the inside diameter of the flange to form a first seat, and similarly, the depth of the seat 6 is selected from the range of 1-5 mm and the outside diameter is the one obtd. by adding the length selected from the range of 0.5-3 mm to the inside diameter of the flange to form a second seat. A surface to be welded is of stock skin, easy to be welded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe connecting member used for transferring gas or liquid.

[0002]

2. Description of the Related Art There are many types of flange shapes and materials and methods of joining with a pipe. When leakage of fluid in a pipe is a particular problem, for example, it has properties such as flammability, corrosiveness and odor. In the case of gas or liquid, the constituent material, shape and method are limited, except for the gasket, where the pipe and connecting material are made of metal, and the insertion welding method of welding and fixing between the flange and the pipe is adopted. Some of them have a groove to make welding easier.

[0003] The flange for such purpose uses steel, stainless steel, color, or the like as a material. Most often, carbon steel is roughly formed by rolling or forging, followed by cutting and finishing, and if necessary, immersing in molten zinc. Rust prevention treatment of plating. When a gasket is used as a leakproof material to be inserted between the flanges, several grooves may be concentrically formed, but in many cases there is no groove and a leakproof material such as packing or gasket is inserted between the flanges Take the method of tightening and crushing.

[0004]

Except for flanges made of stainless steel or colored materials, steel flanges are easily rusted and are galvanized to prevent rust, but this zinc is heated by welding during welding. Vaporized gas can cause a great deal of pain to the welding operator, and gas can enter the build-up portion of the welding surface, generating bubbles and causing fluid leakage.Thus, sand the welding surface prior to the work. Therefore, it is necessary to remove zinc from the welded portion.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a plate flange having a shape which solves the problem of zinc gas accompanying the above welding.

The present invention relates to a steel connecting member to be connected to a steel pipe by welding, wherein the front and rear surfaces of a hole opened in the galvanized steel connecting member to play with the steel pipe. A disc-shaped seat is cut and formed concentrically with the seat.
0.5 mm for any depth selected from the range of mm and the hole diameter.
Equipped with a seat of any outside diameter selected and added from the range of ~ 3 mm, and on the other side, any depth selected from the range of 0.5 to 3 mm and the hole diameter selected and added from the range of 5 to 10 mm A first seat having any outer diameter, and a depth selected from a range of 1 to 5 mm and a depth of 0.5 to 3
A weld flange comprising a second seat having any outer diameter selected and added from a range of mm.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention prevents the zinc formed on the surface from being melted and gasified due to the high heat generated at the connection when the tube and the galvanized flange are connected and fixed by welding. Therefore, it is a flange provided with seats on the front and rear surfaces so as to form a concentric circle with the pipe.

[0008] There are known welding methods for locally melting and connecting separated metals, and various methods are available, and electric welding is mainly used for connecting steel pipes. In order to maintain the strength of this welding, a large amount of current is applied to the connection surface via a welding rod,
The welding rod, the pipe and the flange are instantaneously melted and connected, but the heat accumulation is limited to a local area, so that the effect of the heat on the body material is minimized.

The present invention utilizes the characteristics of welding by electricity or gas to cut the surface of the plated flange surface in a range in which zinc does not reach the boiling or vaporization temperature, and the surface opposite to the connection surface side of the flanges. In consideration of the difference in heat dissipation on the side, a single-stage seat on the connection surface side and a two-stage seat on the opposite surface side provided the purpose of preventing boiling or vaporization. Also, the flange material before plating is the same as the non-plating flange,
When the plating is necessary based on the latter as a reference, the stock is plated and cut to form a concentric circle wider than the required welding area.

The working range of the flange is a seat on the joint surface side of the flanges, and the depth is selected from a range of 3 to 9 mm, and the outer diameter is selected and added to the inner diameter of the flange from a range of 0.5 to 3 mm. On the opposite side, the depth is selected from the range of 0.5 to 3 mm, and the outer diameter is selectively added to the inner diameter of the flange from the range of 5 to 10 mm to form the first seat, which is continuous with the first seat. The depth is selected from the range of 1 to 5 mm, and the outer diameter is selectively added to the inner diameter of the flange from the range of 0.5 to 3 mm to obtain the second seat.

The seat formed on the flange has a nominal diameter of the pipe in the range of 15 to 300 A, preferably 15 to 200 A.
It is applicable to any of the ranges described above, and the size of the seat is also expanded in the range described above with the expansion of the nominal diameter, and it is applicable to a large size whose nominal diameter exceeds 300A, It is more suitable to apply silver rust preventive paint after welding than plating, and having a seat eliminates the risk of gas mixing into the weld due to vaporization of zinc, and because the welding surface is a material A secondary effect was obtained in that the tacking work at the time of piping was easy and the work of sanding for welding was reduced.

[0012]

The flange of the present invention cuts the galvanized surface to provide a seat as it is, so that the melting range of the seat, the pipe surface, and the welding rod does not extend to the galvanized portion.
The heat of the welding operation did not reach the zinc melting temperature outside the seat, and the generation of zinc gas was drastically reduced.

[0013]

1A and 1B show a plate flange, in which FIG. 1A is a front view, FIG. 1B is a cross-sectional view, and FIG. 1C is a cross-sectional perspective view showing a plated portion on a cross-sectional view. FIG. 2 is a cross-sectional view of the raw material 1A before processing, FIG. 2 is a welding state of the flange and the pipe of the present invention, FIG. 4 (A) has no groove, and FIG. In each case, the welding state of the conventional flange and the pipe was shown.

1A and 1B show a plate flange 1 having a relatively small nominal diameter. As the nominal diameter increases, the number of mounting bolts and nuts increases in multiples of four. FIG. 2 shows the material of the plate flange 1 used in the present embodiment, which is also a conventional type. The shape is provided with a hole 4 for inserting a tube in addition to the hole for the bolt and nut, and as it is immersed in a zinc melt and plated, the entire surface is covered with a zinc film.

As shown in FIG. 1 (B), a disk-shaped seat 5 is formed on the front surface 2 (connection surface) by shaving the above-mentioned material, and the rear surface 3
The seats 7 and 6 have a large diameter and shallow depth compared to the small diameter and shallow depth of the seats 5 and 6. It is related to the contact surface and is determined by the remaining area of the contact surface necessary for stabilizing the pipe at the time of insertion. This processing removes the zinc coating on the welded portions of the seats 5, 6, and 7 as shown in FIG. 3C, exposing the material of the material, facilitating welding and stopping the thermal influence during welding on the cut surface. The phenomenon of boiling and vaporizing zinc has been drastically reduced.

Concave seats 5, 6, 7 on front and rear surfaces of flange 1
The difference in the size is explained with reference to the welding state diagram of FIG.
When the pipe is inserted into the flange and welded, welding is performed at two places on the front and rear faces. On the front side, the tip 9 of the pipe 8 is located inside the front face 2, and the seat 5 and the tip 9 without zinc coating are provided. Correspondingly, a weld overlay 10 is applied to this portion, and the rear surfaces correspond to the seats 6, 7 without the zinc coating and the outer surface of the tube 8, and an weld overlay 11 is applied to this portion. The difference between the welded portions on the front and rear surfaces is that the former is the welded surface between the inner periphery of the seat 5 and the pipe end, while the latter is the welded surface between the radial surface of the seat 7 and the outer periphery of the tube, and the combination of the end surface and the inner surface. The shape of the seat was different because of the opposite.

[0017]

Comparative Example FIG. 3 shows a cross section of a conventional flange 1A with or without zinc plating. FIGS. 4A and 4B show a conventional type, and FIG. 4B shows a welding state of a plate flange having a groove on one side. In both cases, the entire surface may or may not be galvanized. In the case of sanding, it is necessary to sand the part to be welded, but this sanding work is dangerous because it is easy to move when the diameter is small, and sparks occur at the time of sanding and the cause of ignition in narrow places etc. Also.

[0018]

The following effects are provided by the flange of the present invention. Boiling and vaporization of zinc from the galvanized flange is less likely to occur, thus significantly improving the safety of welding work. Since the seat is formed by cutting after plating, the welding surface is the skin of the material, and temporary welding and main welding are easily performed. The need for sanding work, which is preparation before welding, has been almost eliminated.

[Brief description of the drawings]

FIG. 1A is a front view of a flange according to an embodiment.
(B) is a sectional view, and (C) is a sectional perspective view.

FIG. 2 is a welding state diagram of the embodiment.

FIG. 3 is a sectional view of a flange of a comparative example.

FIG. 4A shows a comparative example in which a flange has no groove,
(B) is each welding state diagram with a groove.

[Explanation of symbols]

 1,1A flange 2,3 face 4 hole 5,6,7 seat 8 pipe 9 tip 10,11 weld overlay

Claims (1)

[Claims] 1. A steel connecting member connected by welding to a steel pipe, wherein a hole opened in a galvanized steel connecting member (2) for loose connection with the steel pipe (1). A concentric disk-shaped seat is cut and formed on the front and rear surfaces of (2), and the seat is 3 to 9 mm on one surface.
0.5 to any depth and the hole diameter selected from the range of
Equipped with a seat (3) of any outside diameter selected and added from the range of 3 mm, and on the other side, any depth selected from the range of 0.5 to 3 mm and the hole diameter selected from the range of 5 to 10 mm The first seat (4) of any added outer diameter and 1
A welding flange comprising: a second seat (5) having any depth selected from a range of up to 5 mm and any outside diameter selected and added to the hole diameter from a range of 0.5 to 3 mm.