JPS6139608B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a thermal fatigue testing machine.

As conventional thermal fatigue testing machines, a thermal strain self-constraint testing machine, a thermal strain external restraint testing machine, and a mechanical strain superimposition testing machine have been proposed. Thermal strain self-constraint testing machine uses a heating and cooling method that creates a large temperature gradient within the test piece, and repeatedly generates thermal strain by restraining the test piece itself, causing thermal fatigue to the test piece. It is a machine. In addition, the thermal strain external restraint type testing machine restrains a hollow cylindrical test piece at both ends, heats it by direct electricity, and cools the cylinder with gas, repeatedly causing axial thermal strain and causing thermal fatigue in the test piece. This is a test machine that produces Furthermore, the mechanical strain superimposition type testing machine not only applies simple restraint, but also superimposes mechanical strain on the test piece from the outside.
This causes thermal strain in the test piece and causes thermal fatigue.

However, the thermal strain self-constraint testing machine,
In both thermal fatigue testing machines, such as thermal strain external restraint type testing machines and mechanical strain superimposition type testing machines, the test piece is heated by directly applying electricity to the test piece to cause thermal fatigue. Therefore, there was a drawback that it took a long time to evaluate each test piece.

Furthermore, conventional equipment that attaches a test piece to a rotating disk and performs continuous thermal fatigue tests heats the test piece with a burner installed at one location while rotating the test piece at a constant speed, and then cools the test piece. Since the test piece is instantaneously heated by the burner, there is a risk of uneven heating, and since the burner is only installed at one location, it is difficult to maintain the temperature of the test piece at the desired value. This is relatively difficult, and due to the relationship between thermal conductivity depending on the material of the test piece, there were problems such as the need for a burner with a very large heat capacity in order to obtain a heating rate above a certain level.

The thermal fatigue testing machine according to the present invention includes: a disk in which test piece mounting portions are provided at equal intervals in the circumferential direction; a drive portion that applies intermittent rotational motion to the disk with drive and stop periods; A cooling tank containing a part of the plate and filled with a coolant, and a plurality of burners arranged opposite to the test piece mounting part of the disk so as to sequentially heat and raise the temperature of the test piece at different positions. The drive unit is configured to control the drive unit so as to temporarily stop the rotation of the disc when the test piece mounting part and the burner face each other, and the test piece is The test piece mounting part and the burner are heated while facing each other, and the temperature is increased sequentially by the plurality of burners, and then rapidly cooled by the refrigerant.
By repeating the above operations, thermal fatigue is caused in the test piece.

In the present invention, since the burners are arranged to face the plurality of test specimen attachment parts provided on the disk, heating regions equal to the number of burners are formed at a plurality of locations, thereby increasing the capacity of one burner. Can be made smaller.
In addition, the test piece must pass through multiple heating areas to obtain the desired temperature, and the temperature rise occurs in stages, so the temperature increase range in each heating area must be defined and the burner capacity selected appropriately Therefore, the residence time of the test piece in the heating region can be shortened. Furthermore, by configuring the test piece to be heated while the disk is temporarily stopped, uniform heating can be achieved.

Preferred embodiments of the thermal fatigue testing machine according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a perspective view showing the overall structure of a thermal fatigue testing machine according to the present invention. In FIG. 1, the cooling tank 10 has a rotating stainless steel disk 1 on its side wall.
2 is rotatably attached. Further, the rotating disk 12 is connected to a motor 14 so as to be able to rotate intermittently. The motor 14 is controlled by a drive control device (not shown) so as to temporarily stop the disk 12 when a test piece mounting section, which will be described later, faces the burner. Furthermore, the rotating disk 12
A plurality of test pieces 16 are attached at predetermined intervals on one surface of the test piece. In the embodiment shown in FIGS. 1 and 2, a total of eight test pieces 16 are installed at an angle of 45 degrees, and three of these test pieces 16 are always above the cooling tank 10. The remaining five test pieces 16 are placed so as to be immersed in the coolant in the cooling tank 10, as shown in FIG. As shown in FIG. 3, the test piece 16 is attached to the rotating disk 12 by jigs 18 and 20 that constitute the test piece attachment part, and a thermocouple 22 is attached to the test piece 16. This thermocouple 22 is connected to a temperature measuring device (not shown).

In FIG. 1, burner gas pipes 26, 26, and 26 branch from the main gas pipe 24, and burner gas pipes 26, 26, and 26 each branch from the main gas pipe 24, and a burner 2
8, 28, 28 are attached. Burner 28
As shown in FIG. 1, three test pieces are arranged, one each corresponding to the position where three different test pieces 16 attached to the rotating disk 12 exposed from the coolant in the cooling tank 10 are temporarily stopped. has been done. Therefore, when the rotating disk 12 rotates intermittently by 45 degrees, the test piece 16 exposed from the coolant is heated successively from the burner 28 on the right side in FIG. 1 to the stop position.

Note that the cooling liquid in the cooling tank 10 may include water,
Oil, brine, etc. are used.

The embodiment of the present invention described above operates as follows. First, the rotating disk 12 is rotated intermittently by 45 degrees, and the test piece 16 is sequentially heated from the burner 28 on the right side in FIG. 1 at the stopped position.
At the stop position immediately before cooling, the burner 28 on the left side of FIG.
When the temperature reaches ℃, it enters the cooling tank 10 and is cooled. When the rotary disk 12 rotates again by a predetermined angle, the test piece 16 is exposed from the coolant in the cooling tank 10, is heated by the burner 28, and when it reaches a predetermined temperature, is cooled in the cooling tank 10. Thermal fatigue occurs in the test piece 16 by repeating this operation, but the temperature change of the test piece 16 in the example related to the present invention is as shown in FIG. The evaluation time can be extremely shortened.

Furthermore, since the rotating disk 12 rotates intermittently at intervals at which the test pieces 16 are arranged, and the burners 28 are arranged corresponding to the positions where the test pieces 16 temporarily stop, Sufficient heating can be performed. Further, since three burners 28 are arranged, one at different positions where the test piece 16 temporarily stops, the capacity of each burner 28 can be reduced, and furthermore, the capacity of each burner 28 can be reduced. can be heated evenly and quickly. Note that the set temperature can be controlled using a simple timer.

As explained above, according to the thermal fatigue testing machine according to the present invention, a plurality of burners are arranged facing a plurality of test pieces attached to a rotating disk, and a plurality of burners are positioned in a rotation area of the rotating disk. By controlling the coolant that cools the test piece and the driving part of the disc so that it temporarily stops when the test piece faces the burner, the test piece can reach the temperature required for thermal fatigue testing. Reduces the heating time and reduces the burner 1 required for the heating.
Excellent effects such as being able to reduce the actual capacity and evenly heating the test piece can be expected.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the structure of an embodiment of a thermal fatigue testing machine according to the present invention, FIG. 2 is a front view showing the arrangement of test pieces on a rotating disk in the embodiment according to the present invention, and FIG. FIG. 4 is a sectional view showing the structure of a test piece mounting portion in an embodiment of the present invention, and FIG. 4 is an explanatory diagram showing a temperature change of a test piece in an embodiment of the present invention. 10...Cooling tank, 12...Rotating disk, 16...
Test piece, 28...Burner.

Claims (1)

[Claims] 1. A disk in which test specimen mounting portions are provided at equal intervals in the circumferential direction, a motor that provides intermittent rotational motion to the disk with drive and pause, and a coolant that encloses a portion of the disk. A cooling tank filled with A thermal fatigue testing machine characterized in that the motor is controlled so as to temporarily stop the rotation of the disk when the burners face each other.