JPS6210222A - Annealing method for weld zone of thin-walled vessel and cooler to be used for said method - Google Patents

Abstract

PURPOSE:To prevent the transfer of heat to parts except a weld zone and to suppress the strength decrease of a vessel material by installing a thin-walled vessel into a vacuum vessel and heating the weld zone thereof and cooling both sides of the weld zone at the same instant. CONSTITUTION:Semi-spherical shell bodies B, C of a motor case A are butted to each other and a band heater 10 and a cooler 20 are attached thereto via a mandrel 21. The assembly is put in a vacuum chamber and a vacuum state is maintained therein. The heater 10 is energized to heat the weld zone D and at the same time the cooler 20 is operated. Oil is first supplied to a cylinder 53 to project a piston rod 54 and a slider 50 is advanced via driving head 55 and a rod 57 upon operation of the cooler 20. Then a collet 25 advances in a radial direction via a tapered surface 51 and a slope 40 of the collet 25 and a cooling part 29 contacts with both sides of the weld zone D in the mid-way thereof. Water is fed from a inlet hose to refrigerant passages 32 of all the collets 25 of the cooler 20 to absorb the heat to be applied to the part near the weld zone D. The water is delivered from an outlet hose. The application of the heat to the parts except the weld zone D is thereby substantially obviated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for annealing the welds of a thin-walled container, such as a motor case of a spherical rocket motor, and a cooling device used in this method.

[Technology background]

Since the spherical rocket motor is normally located at the top stage of a rocket system and carries an artificial satellite, etc., it is necessary to reduce the weight to the utmost. Because the capacitance of this butt part is small, the temperature near the weld becomes high.
Furthermore, when titanium alloys are heated to high temperatures, their strength significantly decreases due to over-aging. For this reason, sufficient annealing must be performed after welding.

[Conventional technology]

First, the structure of a motor case of a titanium alloy spherical rocket motor, which is the subject of this prior art and the embodiments to be described later, will be explained with reference to FIG. A is a thin-walled motor case made of titanium alloy, and this motor case A is the first half. The constituting shell B and the shell C constituting the latter half are butt welded at the welding part. E is a hole for attaching a small diameter igniter formed at the front end of motor case A, F is a hole for attaching a large diameter nozzle formed at the rear end of the same, and G is a weld on motor case A. This is a 7-lunge for mounting a rocket motor, which is formed slightly to the rear of the part.

Conventionally, as shown in FIG. 9, there has been a method for annealing the welded portion by placing a band-shaped heater 1 on seven flange Gs. This band-shaped heater 1 and its usage will be explained based on FIG. 10. Reference numeral 2 denotes a heater, which is brought into contact with the welded portion of the motor case A. 3 is a heat insulating material which prevents the heat of the surrounding heater 2 from dissipating from the heater 2t-3 direction. 4 is a casing that holds the heat insulating material 3 and the heater 2. Reference numeral 5 denotes an outer shield case, which has a U-shaped cross section and surrounds the casing 4. Is 6, 6 a seal, or a gap between outer shield case 5 and motor case A? It is provided so as to close the outer shield case 5 and isolate the inside of the outer shield case 5 from the outside air. Reference numeral 1 denotes an inert gas, which is filled in the outer shield case 5 and the motor case interior to prevent the titanium alloy motor case A from being oxidized by the heat of the heater 20.

[Problem that the invention seeks to solve]

By the way, in the conventional annealing method, the inert gas 7 inside the motor case causes convection by the heat of the heater 2, and the heat transferred by the convection heats parts of the motor case A other than the welded parts. become. Then, since motor case A has a small heat capacity, it will be greatly affected by heat, and the heat will cause deformation such as shearing of the crystals that make the material of motor case A, which may reduce the strength of the material of motor case A. It had the following drawback.

The reason for this is that the heat that should be applied only to the welding area is also applied to other parts of the motor case A, which is a thin-walled container. Therefore, a technical problem of the present invention is to prevent heat that should be applied only to the welded portion from being applied to other parts of the thin-walled container.

[Means for solving problems]

The first technical means of the invention for solving this technical problem is a method for annealing a welded part of a thin-walled container, in which the thin-walled container is placed in a vacuum chamber and both sides of the welded part are cooled while the welded part is being heated. It is.

On the other hand, the technical means of the second invention includes a mandrel fitted into a thin-walled container, a collet held by the mandrel so as to be able to advance and retreat in the radial direction, and a welded portion formed on the way of the collet advancing. Welding of a thin-walled container comprising a cooling part formed in the collet so that it can come into contact with both sides, a refrigerant passage formed in the collet near the cooling part, and a driving means for driving the collet in the advancing direction. This is a cooling device used for partial annealing.

〔Example〕

Next, embodiments according to the present invention will be described. In Figure 1,
Reference numeral 10 denotes a heating device, which in this example is a band-shaped heater, and is placed on the flange G. This band-shaped heater 1
0 is divided into a plurality of segments 11, four in this example, as shown in FIGS. 2 and 3, and each segment 11 is connected to a bolt nand 13 via a spring 12 and welded as a whole. It has an annular trap that can surround the area. The heater 2 is in contact with the welded part and is surrounded by the heat insulating material 3 and the casing 4, as in the conventional case.
is held by a stay 14. Numeral 15 is a thermocouple, and a plurality of thermocouples (eight in this example) are attached to the band-shaped heater 10, and they are brought into contact with the welding part by a spring 16 for welding. ) is connected.

Returning to FIG. 1 again, 20 is a cooling device, the details of which are shown in FIGS. 4 to 7. In Fig. 4, reference numeral 21 is a hollow mandrel, the front end of which is attached to the igniter in the same manner as hole E through a support 22, and the rear end of which is attached to the nozzle deeper than hole F. The rear end portion is attached to the nozzle in the same way as the hole F through a support 23. Reference numeral 24 designates seven flanges protruding from the middle part of the mandrel 21, and reference numeral 25 designates a plurality of collets held by this flange 24, with elongated holes 2 formed at the base end of the collets 25.
6 and a pair of pins 27 inserted through the elongated hole 26 and screwed onto the 7 flange 24 so as to be able to advance and retreat in the radial direction.

Each collet 25 is formed into a fan shape as shown in FIG.
4 and are arranged in a disk shape as a whole. The size is set so that the outer periphery of the collets 25 arranged in a disk shape can come into contact with the welded portion during the advance process. Further, as shown in FIGS. 6 to 8, the collet 25 has a circumferential groove 28 formed on its outer circumferential surface, and both sides of the circumferential groove 28 serve as cooling portions 29, 29. Note that the depth and width of the circumferential groove 28 are the same as the welded portion D? Define it so that it can be tolerated.

Reference numeral 30.30 denotes an arc-shaped groove with closed ends formed on the outer peripheral side surface of the collet 25 near the cooling section 29.29!
! 11.31.31 is a cover plate that closes #l130.30. These grooves 30.30 and the cover plate 31.31 form a coolant passage 32.32. 33 is a pipe connected to both ends of one refrigerant passage 320, and 34 is a pipe connected to both ends of the other refrigerant passage 32. 35 is a connector fixed to the collet holder 5. In FIG. 5, 36 is a connector that connects to an inlent hose (not shown) for refrigerant, such as water, and 3γ is a connector that connects to the outrent hose (not shown). Water is supplied from the inlent hose through the pipe 33, connectors 35, 36 and flexible hose 38.
The refrigerant is circulated through one of the refrigerant passages 32 through the connector 3T.
and is piped to the outlet from the outrent hose. The same applies to the other refrigerant passage 32. Returning to FIGS. 6 and 7, 40 is a tapered inclined surface formed at the base end of the collet 25, and 41 is a keyway carved into the inclined surface. Also, the slope has the same tendency as the above-mentioned slope. In FIG. 4, reference numeral 50 is a cylindrical slider that is slidably fitted into the middle part of the mandrel 21 and has a tapered surface 51 that matches the inclined surface 40 of the collet 25. Side 4
0 is engaged. Reference numeral 52 denotes keys that are engaged with the key grooves 41 of the collets 25 and fixed to the slider 50, and these keys 52 prevent each collet 25 from rotating. 53 is a cylinder fixed inside the mandrel 21, 54 is its piston rod, 55 is a drive head fitted inside the mandrel 21 and fixed to the piston rod 54, 56 is a drive hole formed in the mandrel 21, and 5γ is a drive hole. This is a rod that connects the drive head 55 and the slider 56 through the hole 56. 58.58
is a hose connector attached to the cylinder 53. These slider 50, cylinder 53, piston rod 54,
The drive head 56, the rod 5γ, and the hose connector 58 constitute driving means for the collet 25. 60
is a frame body to which the support 22 and the support 23fc are fixed. 61 is an adapter for fixing the support 22 to the frame 60, and 62 is an adapter for fixing the support 23 to the frame 60. The above is the configuration of the cooling device 20. To attach this cooling device 20 to the motor case A, first, the adapter 62 is removed from the frame 60 and the motor case A is placed on a workbench with the adapter 61 side facing down. Next, with the collet 25 and the support 23 removed from the mandrel 21, the mandrel 21 and the motor case A are fixed to the adapter 61 by the support 22. Next, to install the nozzles, a worker enters the motor case through the hole F, attaches each collector 25 to the mandrel 21 in the manner described above, and connects the refrigerant passage to the through piping described above. Further, the hose connectors 58, 58 are connected to a hydraulic power source via switching valves (not shown), and the worker exits the motor case A. Thereafter, the mandrel 21 is attached to the frame 60 via the rear end supporter 23 and the adapter 62.

After the band-shaped heater 10 and the cooling device 20 are attached to the motor case A in this manner, the motor case A is placed in a vacuum chamber TO as shown in FIG. 1, and the inside of the vacuum chamber 70 is evacuated. Thereafter, the band-shaped heater 10 is connected to a power source (not shown) via the heater cord 1γ to heat the welded portion of the motor case A, and at the same time the cooling device 2
Activate 0. In order to operate the cooling device 20, first, pressure oil is supplied to the cylinder 53 via the switching valve to cause the piston (! 7)'' 54 to protrude, and then the piston (! The slider 50 is advanced.Then, the collet 25 advances in the radial direction via the tapered surface 51 and the inclined surface 40 of the collet 25, and on the way, the cooling parts 39 and 39 come into contact with both sides of the welded part. At this time, the water supplied from the inlent hose circulates in the refrigerant passages 32 of all the collets 25 of the cooling device 20, and the water is added to the vicinity of the welding part.Heat is absorbed. It is sent out from the hose.

〔Effect of the invention〕

In the present invention, when annealing is performed while heating the welded part of a thin-walled container, the thin-walled container is placed in a vacuum chamber, so the heat applied to the welded part is not absorbed by convection caused by inert gas, etc., as in the conventional method. There is almost no migration to other parts of the thin-walled container.

Further, in the present invention, since both sides of the welded portion are cooled during annealing, almost no heat is transferred to other parts of the thin-walled container even by conduction on the thin-walled container. In this way, in the present invention, almost no heat is applied to areas other than the welded part, so deformation such as crystal shift that makes the thin-walled container material such as titanium alloy and oxidation of the thin-walled container material occur, and the resulting strength of the thin-walled container material is increased. The decline can be prevented.

[Brief explanation of the drawing]

Is Fig. 1 an embodiment of the present invention? The explanatory diagram shown in Fig. 2 is the first
3 is a sectional view taken along the line 1-1 in FIG. 2, FIG. 4 is a half-cut sectional view taken along the line
The figure is a plan view of the main part of FIG. 4, FIG. 6 is a partially enlarged view of FIG. 5, and FIG.
The figure is a cross-sectional view taken along the line ■-■ in Figure 6. Figure 9 is an explanatory diagram illustrating a conventional method and device.
FIG. 3 is an enlarged line cross-sectional view. 10...- Band-shaped heater 20... Cooling device 21.
・・Mandrel 25・Collection 29.29・
...Cooling part 32.32...Refrigerant passage γ0...
Vacuum chamber patent applicant Nissan Motor Co., Ltd. Figure 9 Figure 10 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] 1) A method for annealing a welded part of a thin-walled container, in which the thin-walled container is placed in a vacuum chamber and both sides of the welded part are cooled while the welded part is being heated. 2) A mandrel that can be fitted into a thin-walled container, a collet that is held by this mandrel so that it can advance and retreat in the radial direction, and a collet that is so arranged that it can come into contact with both sides of the welded part while it is advancing. A cooling device used for annealing a welded part of a thin-walled container, comprising: a cooling section formed in the cooling section, a refrigerant passage formed in the collet near the cooling section, and a driving means for driving the collet in the advancing direction.