JPS59141327A - Flanging method of metallic pipe - Google Patents

Abstract

PURPOSE:To form a flange on a metallic pipe without cracking the pipe in a method for beading and flanging the midway of the metallic pipe by setting the bending R in the flanging at a specific value. CONSTITUTION:One end of, for example, a thin walled cylindrical exhaust pipe 1 is gripped, and a bulging tool 3 is inserted into the pipe. While the tool is rotated eccentrically from the axial center of the pipe, the rate of eccentricity is increased gradually to flare the inside wall of the pipe in a diametral direction, thereby forming a bulging part 5 having a V-shaped section. A spring inserting tool 6 is thereafter disposed oppositely to one end of the pipe 1 and an annular spring 7 which is reduced in the diameter and has the length of one turn or below when the flanging state ends (when expanded) is loaded into a guide 6a having the bore equal to the bore of the pipe 1. The front end of the tool 6 is pressed to the end of the pipe 1 and thereafter a rod 6b is projected forward to insert the spring 7 up to the bulging part 5 and is thus repulsively fitted therein. The part 5 is then pressed from both side by means of a die and a punch so as to be buckled and diametrally projected, thereby forming a flange 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a flange in the middle of a metal tube with a radially protruding part, especially in the flange! '＞：
(1) Regarding fQ-specific Seiko 1 Bosho λ・j measures.

Conventionally, for example, a 1-in-1 lumen pipe is used to connect air pipes arranged separately on the engine side and body side of a car, Fig. 7. It is known that there is no such thing as shown in FIG. Connect the vehicle body side exhaust pipe l) with a correspondingly formed connecting end (luer 1) through the seal ring C to the joint. L + Jl Kebutsu ζ 1, 1) outer circumference (2 welded fastening flange +, l , (! Holt 1... O J
, Binatuto9...niJ,su,ka-)spring))・
. . ., apply a force in the direction of tightening () and tighten.
Second. It is designed to connect the trachea a, l', and + of both 1 and 1 without leakage while absorbing vibrations.

Deshi C,..., l-Note 1- Molding of flange a of engine side exhaust pipe a (,11, First, insert the molded shell 1h13 into the flange molding part 5 of the trachea a in 4.11), and By pressing the molding tool against the inner circumference of the exhaust pipe a and rotating it eccentrically with respect to the axis of the exhaust pipe a, the molding tool is pressed against the inner circumference of the exhaust pipe a. pressurize the exhaust pipe a in the axial direction of the exhaust Y < a to make the bulge protrude in the radial direction. A method has been adopted in which 7 lanciers a 1 are formed by <flanging process>.

However, in the conventional flange forming method described above, as shown in FIG. 8-f, the [110JIIn
] On the inner wall of part x, a2, a deep crack occurs due to the "machining overhang" that occurs when flanging is applied.
During use, this crack became the starting point for 7 lunges; + t h
``The present invention was made in view of these points. The object of the present invention is to provide a method for forming a flange on a metal tube such as an IJI trachea without causing a crack, based on this knowledge.

In order to achieve this objective, the method of the present invention (1)
Well, it is a method of forming -C゛fushinji by protruding the middle of 6'bi'Y'+°' (in the direction of tY 7'J) (,9
Inflate the molding tool 1i into the metal tube, and place the 1l (13 out molding 1.! 4 times 6 times J', the metal Lji inside the tube -' + clear' mh direction (push 11 m) (Atej; Akiro 4
Form g5, then ty (Y 'i a?j set link-like sub 1) link spring l111 foot (:
Gold) 5 Bt<A: '-('Insert the IM of the 6TIiJX tube into the inner wall of the ridge; fit 1 ring-shaped sub-piece into the inner wall of the crest, and then insert the metal tube into the 4-piece tube.) Add the bulge 4 part in the radial direction (
As the bulge protrudes, the IJ ring should be expanded (7, 1).
At the tip of the llt'B' protruding part of the metal tube,
Insert the long-shaped snoring ring and make a full flange.
on joint (this J: -> (to the flange (13 (bending) part of the inner wall q) di] C B R to 1 temple [to 1?
1 “It is a sign of preservation.

Hereinafter, the present invention will be described in detail with reference to the drawings and embodiments (Figs. 1 to 5).
1) Forming a radially protruding flange 41 at one end r111 of the trachea in the shape of a thin circle 7 (J) An example will be shown below. First, as shown in Figure 1, after being cut to a predetermined length in the cutting process, the force on the cut surface was removed by approximately J5. One end of a thin circular straight pipe 1 for an exhaust pipe is attached to a clamp 2.
It is divided into ten halves, each of which is connected to a holder (not shown), and the holder is vertically connected to the Ji23.
LL, the above-mentioned straight pipe 1 is engaged J5 and its removal is performed by separating (hyperactive U-).

Next, with the straight pipe 1 held by the clamp 2, the first
As shown in the figure, a bulging tool 3 is inserted into the straight pipe 1 to bulge the middle of the 1i'1 pipe 1 in the radial direction.
consists of a shaft portion 3a that is attached to the butt 4 and a disc-shaped molded portion 3b formed at the tip of the shaft portion 3a, and is a hydraulic syringe (not shown in the figure) disposed inside the telephone 4. Due to the operation, the shaft center rotates with an eccentricity of 'C' relative to the center of the straight pipe, and this eccentricity is gradually increased. This is a beading culm that expands the inner wall of the straight pipe 1 in the radial direction to form a bulging portion 5 having a V-shaped cross section. ,, 1-J is applied to shilling 2 facing the swelling part 5, - 1 can be summoned in the radial direction (vertical direction)ff Darkness + Nislide part (-(')i) -
:>'-(, 1, A spring (not shown) is inserted between the slurry R portion 2a and the holder (J>
During the formation of the bulge 5 of the straight pipe 1 (the bulge 5
The bulging portion 5 moves outward in the radial direction while immediately increasing the shapeability of the tip of the bulged portion 5.

After beading one culm, 4J shown in Fig. 2,
Uni, ring-shaped spring 7 is used in place of the above-mentioned FX7 spring 4.
11゛1 tube 11 spring for entering 1 dwarf shell 6
'ali'! and '1'.

A cylindrical spring guide 6 with an inner diameter equal to that of the strip ring insertion IC 31, 11, Il'1 part 11,
a, and the sliding C (spring push rod (51) fitted in u or j') from the rear end (right end in Fig. 2) of the sprinkling guide (J') in the direction of the axis 1j. ,
:The spring guide 6a has a ring-shaped spring in a state in which one spring is contracted. The ring-shaped spring 7 (11, "I' fY r
A spring cable with a circular cross section is wound into a ring shape.
At the end of the culm (when the ring-shaped spring 7 is expanded) a
The length is limited to no more than 3 rolls.

After that, as shown in Fig. 3, the front 0i1i of the above-mentioned spring offshore fitting 6 is directly τ (1 pear, 11
By protruding the prong (51) forward, the ring-shaped spring 7 is connected to the bulge part in the 11), 1,
"C" Insertion - (The ring-shaped spring 7 is elastically fitted to the inner wall of the bulging portion 5 of the straight pipe 1 (Spring Y hair I pushing step).

Then, when the above-mentioned pushing process of spring wire A is completed, as shown in FIG. The ends t, - of the straight pipe 1 are fitted with a bunch 9 for flanging the bulge 5 of the straight pipe 1, while holding the pipe 1 in place. The bunch 9 is provided with a fitting hole 9a that fits in the outer peripheral surface from the bulge 5 of the straight pipe 1 to the end of the straight pipe 1, and a hole 9a is formed in the center of the fitting hole 9a. A centering jig 10 that fits into the straight pipe 1 is provided.

In this state, press pan f9 to the right to press '+l'1. Part!Uwo-・i': Ii
'Ilsa IL, IY Buno's protrusion 1! Ru. At this time, the ring-shaped snoring 7 that fits into the inner wall of the bulge 5 expands, and the pan 19 further expands. The rear end surface of the die ε3 and the front end surface of the punch press the -J'CIh1i5 exit part 55 from the front and back (when the flange is completely formed, the fifth
As shown in the figure, the link-shaped snoring 7 is inserted into the inner wall of the bent portion 11a around the flange 11 (flange 11 is formed).
<Francine 9' J R') ,, 12 C
1,1+'t Tube 1 (7) Other E Inner 2++* Join/This is the support 1, ゛j part that supports the plane j'7<-l.

Here, it is formed in the flanging process described in -1.
Signal flange 11 (, 2 (13 bending force 1 opening +'
) 11'A to IY are bent according to the wire radius of 1゜ of the ring-shaped spring 7, and the bending R of the inner wall is never less than 1゛1.1'c .

Therefore, this "Ushi-C formed flange 1
1, ``2'' r is a specific value, for example 0.5-1.0m++
By setting J, no cracks will occur in the inner wall of the 1 I can do it.

Since the ring-shaped spring 7 is inserted into the inner wall of the bent portion 11a, it is necessary to mold and cover the ring-shaped spring 7 with a flange 11 having a good outer diameter shape.

In the above embodiment, the ring-shaped spring 7 is formed of a cable wire having a circular cross section with a radius of 1°, but for example, as shown in FIG. A ring-shaped spring 7' formed of a wire whose inner peripheral side has a rectangular cross section may be used.

Further, in the above embodiments, the present invention was applied to a thin circular tube-shaped trachea, but it is not possible to apply it widely to other metal tubes.

According to the flange forming method of the present invention as described above, the inner wall of a metal tube is expanded in the radial direction to form a bulge, and then a ring-shaped sub 1) ring is attached to the bulge. Insert and further ↑flex? ′+; +-J to pressurize in the axial direction;
-) (The bulge is protruded in the i direction and the 116
Inside the 3 protruding tips! Since a ring-shaped spring is inserted in 1i' to form a slight bend, specify the bend 1st of the inner wall of the 15-rilo bend 131111 part (15).
ll'l 1-(Please be sure to prevent the occurrence of cracks on the inner wall described in 1-1-11('') or (2-゛, yo-)C. This makes it possible to form flanges with different shapes.

[Brief explanation of the drawing]

Figures 1 and 1 (J) show the molding process of an embodiment of the present invention.
``Cross-sectional view showing the process'', Figure 2 t, 1, Spring Y\]
State 4 before the pushing process - J' Ili side view, Figure 3i tJ, state after the spring wire pushing 1 - stage is shown! 1 is a sectional view, FIG. 4 is a sectional view of the flanging process, FIG. 5 is a sectional view of the molded flange, and FIG. 6 is a sectional view of a modified example of the ring-shaped spring. Figure 7 shows the conventional fushino, 1 system - 1 inch, Ai
, and FIG. 8 is an enlarged sectional view of the flange portion. 1... Image quality, 33... Swelling molding tool, Swelling part for 5, (
3... Sujiring (application, 7,7'...Ring 1
Spring, 11... Fufunshi, 11J1... 1 part bent.

Claims (1)

[Claims] (1) A method of forming a nosande by protruding the middle of the metal piece in the radial direction, first inserting an expansion molding tool into the metal layer and rotating the expansion molding tool. Particularly, the inner wall of the metal color is expanded in the radial direction to form a bulge, and then the ring-shaped spring with its diameter reduced is inserted into the bulge inside the metal color using a spring inserter. Insert C gold 11Jl
The inner wall of the bulging part of the i-tube [the ring-shaped spring springs 1θ]
(When the metal tube is pressed in the axial direction of the metal tube to cause the bulge to protrude in the radial direction, the ring-shaped spring expands as the bulge protrudes, A method for forming a flange on a metal tube 1, characterized by forming a flange in which a ring-shaped spring is inserted in the inner wall of the tip of the bulging portion of the metal tube.