JPS6061171A - Brazing method of part where pipe is fitted to cylindrical part - Google Patents

Abstract

PURPOSE:To braze efficiently and satisfactorily a fixing member to a base metal without damaging the base metal by mounting the fixing member fitted perpendicularly with a pipe to a supporting base which is under stoppage or rotation, placing a brazing material around the fitting part of the pipe and heating uniformly the fitting part of the fixing member. CONSTITUTION:A nozzle 6 is perpendicularly inserted and fitted to a fixing member 2 consisting of an aluminum alloy, etc. and the fixing member is mounted to a rotary supporting base 9. A brazing filler metal 7 is placed on the surface in the part where the nozzle 6 is fitted to the member 2. The periphery 5 in the fitting part of the member 2 is uniformly heated 8 to braze said part. An aluminum alloy member with which overheating is prohibitive is also heated to the adequate heating temp. and is satisfactorily brazed. The arrangement of the burners 8 or the like is devised to accomplish uniform heating if the base 9 does not rotate. The brazing of the base metal is accomplished with higher efficiency than in the conventional brazing with discrete manual operation without damaging the metal.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for brazing a pipe fitting to a cylindrical body.

Conventionally, in order to cool a screw 1 in an internal combustion engine, for example, as shown in FIG. is fixedly supported, and lubricating oil supplied to the passage 32 by an oil pump is passed from a nozzle 6 extending into the inside of the cylinder 36 to the piston 3.
The liquid is ejected around the inner wall surface of the screw tube 7 and the connecting rod 39 to cool it.

Conventionally, copper or a copper alloy has been used for the nozzle 6 and the fixing member 2, and the two are bonded to each other by soldering. Attempts have been made to process the nozzle 6 and the nozzle 6, and to join them together by brazing. The condition is to use hard solder.However, aluminum has a much better thermal conductivity than copper, and the melting points of the base metal and brazing metal are close to each other, so it is very difficult to use even when done by hand. It is said that it is very difficult to automate the process of brazing.

For example, as shown in FIG.
A nozzle 6 is fitted into the cylindrical part 5, and an annular brazing material 7 is fitted onto the nozzle 6 and supported on the upper end surface of the cylindrical part 5. 7 (pu is not enough, so heat gradually starting from the cylindrical part 5 with a large heat capacity so that the flame does not reach the brazing filler metal 7, and the brazing filler metal 7 gradually melts and the cylindrical part 2 and nozzle 6 fit together.) It is necessary to make sure that the melt penetrates into the joint. Not only does this type of brazing take a lot of work, but it also causes unevenness in the finish of the solder, and in the unlikely event that the soldering part peels off and the nozzle 6
If it falls off, it may damage the inner circumferential surface of the cylinder, or the cooling of the piston may deteriorate and the piston ring may burn out.
There is.

Of course, after fitting the nozzle 6 to the Tokubugetsu 2 and attaching the brazing filler metal 7, insert this into an atmospheric furnace to melt the filler metal (brazing is possible if the brazing filler metal is sized like this). Yes, but
This increases the equipment cost, which actually causes an increase in cost compared to a conventional nozzle using a copper alloy.

An object of the present invention is to automatically perform the brazing work of the pipe fitting part to the cylindrical part, and to provide an economical method of soldering the pipe fitting part to the cylindrical part, which can provide a homogeneous joint. The attached section provides the method (in 2 and 2).

For this reason, in the method of brazing a pipe fitting part to a cylindrical part according to the present invention, the fixing member is supported upright, the pipe is faced to the cylindrical part of the front two fixing members, and the upper end of the cylindrical part is A ring-shaped brazing material surrounding the pipe is attached to the pipe, and the pipe is placed with the mouthpiece of the whistle facing the lower end of the cylindrical part so that the flame hits the lower end of the cylindrical part and flows toward the upper end. The present invention is characterized in that after the entire circumferential surface of the cylindrical portion is heated by the flame, the brazing filler metal melts and flows into the gap of the fitting portion.

The present invention will be explained based on examples. As shown in FIG. 3, a recess 10 is provided in the center of the rotary table 9 driven by a rotary shaft 13, and a proximal end portion of the fixing member 2 having the hole 3 is inserted into this through a heat insulating material 30. The cylindrical portion 5 is fitted and supported, and the cylindrical portion 5 is placed in an upright state. Preferably, one or more blowing i! 8 is placed, and this whistle 8
The direction of the fixing member 2 is inclined slightly upward toward the base end of the cylindrical portion 5 of the fixing member 2.

A nozzle 6 is fitted into the cylindrical portion 5 , and an annular brazing material 7 fitted onto the nozzle 6 is supported on the upper end surface of the cylindrical portion 5 .

When the flame is ejected from the whistle 8 toward the lower end of the cylindrical portion 5, the flame flows upward along the outer wall of the cylindrical portion 5.

Since the fixed member 2 is rotated together with the rotating table 9, the wall portion of the cylindrical portion 5 is heated uniformly over the entire circumference.

5- When the cylindrical part 5 is first heated to a temperature almost equal to the melting point of the wax 7, the brazing filler metal 7 melts and flows into the gap between the nozzle 6 and the cylindrical part 5. In this case, the tip of the whistle 8 should be approximately 5QcR+ away from the cylindrical portion 5, and the angle of the tip of the tip of the whistle 8 should be around 25°. It is preferable to point. If the inclination angle of the crater is smaller than this, it tends to absorb heat locally,
It is difficult for the cylindrical portion 5 to be heated uniformly as a whole. In addition, if it is large, heat transfer becomes poor and the temperature distribution becomes rough and non-uniform.

Propane gas and oxygen are used as gases for heating, and their blowing pressures are suitably 0.2 kg/cv and 0.5 kg/cII12, respectively. The brazing material 7 melts in about 60 seconds and brazing is completed.

As a brazing material, for example, AM-05 manufactured by Nippon Alumitsu
5, etc., the flux can be peeled off and removed into the cylinder simply by cooling with water, so there is no risk that the flux will not be removed and enter the lubricating oil and adversely affect the lubricated parts.

=6- As described above, in the present invention, since the flame from the soft tube flows from the base end side of the cylindrical part 5 to the upper end side over the entire circumferential surface, the cylindrical part 5 is heated, and then the brazing material 7 is melted. Since it flows uniformly into the gap between the fitting part of the cylindrical part 5 and the nozzle 6, a perfect joint can be obtained. In other words, the brazing filler metal 7 is not directly heated with a flame, but the fitting portion between the cylindrical portion 5 and the nozzle 6 is heated uniformly as a whole, so that the brazing filler metal 7 placed at the upper end of the cylindrical portion 5 is The flux melts from the inside and flows smoothly into the fitting part, leaving flux at the end of the cylindrical part.

The flame from the soft tube 8 flows upward along the cylindrical part 5 and surrounds the brazing filler metal 7, so that the brazing filler metal 7 melts from the part where it contacts the end surface of the cylindrical part 5 due to heat transfer from the cylindrical part 5, and the cylindrical part 5
Since the filler metal 7 immediately flows into the fitting part between the filler metal 7 and the nozzle 6,
Flux remains around the solder, preventing leakage of the filler metal.

The heat transferred to the cylindrical part 5 by the flame of the soft tube 8 is transferred both upward and downward along with the flame, but since the lower end is supported by the rotating table 9 made of a heat insulating material, the heat escaping from the lower end to the outside is This is a small amount, and the cylindrical portion 5 is heated almost uniformly in this length direction.

Furthermore, by the time the flame from the soft tube 8 reaches the brazing filler metal 7, the temperature has become low, and the brazing filler metal 7 is only enveloped by the upward flow of the flame and does not come into contact with the flame directly, so the brazing filler metal changes in quality. can be avoided.

According to the present invention, it is now possible to automatically braze the vibrator fitting part to the cylindrical part made of aluminum using a fixed soft tube, which has been considered difficult in the past, using very inexpensive equipment, thereby reducing material costs. It is possible to reduce the production cost and reduce the manufacturing cost.

As shown in FIG. 4, if a large number of soft tubes 8 are arranged around the brazing part, the fixing member 2 fitted with the nozzle 6 will not necessarily rotate, but will be able to move through the heat insulating material 29. Support stand 30
It is possible to braze it with a fixed support.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of a bis-Front cooling system for an internal combustion engine to which the method of the present invention is applied; The figure is an explanatory diagram for achieving the method of the present invention, and FIG. 4 is an explanatory diagram for achieving another method of the present invention. 2: Fixing member 5: Cylindrical part 7: Brazing material 8: Soft tube 3
1 Niji Linda Block 33: Eye bolt patent applicant
Isuzu Motors Co., Ltd. Patent applicant Daian Kogyo Co., Ltd. Agent Patent attorney Toshio Yamamoto 9- 21- Figure 3 637 -7 Figure 2 [2138 32 39 Figure 4

Claims (3)

[Claims] (1) Support the fixing member upright, fit a pipe into the cylindrical part of the fixing member, attach an annular brazing material surrounding the pipe to the upper end of the cylindrical part, and set the flame to the lower end of the cylindrical part. A blowpipe is placed with the mouth of the blowpipe facing the lower end of the cylindrical part so that it flows along the upper end of the cylindrical part, and after the entire circumferential surface of the cylindrical part is heated by the flame, the brazing filler metal melts. A method for brazing a pipe fitting part to a cylindrical part, characterized in that the flow flows into a gap in the fitting part. (2) Pipe fitting to the cylindrical portion according to claim (1), wherein the fixing member is rotated around its central axis so that the entire circumferential surface of the cylindrical portion is heated by the flame. Brazing the parts is a method. (3) Pipe fitting to the cylindrical portion according to claim (1), wherein a large number of blowpipe are arranged on the outer peripheral side of the fixing member so that the entire circumferential surface of the cylindrical portion is heated by flames. Brazing the joint is a method.