JPH0580978B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a load loading device for a constant load testing device for materials, and in particular, to quantify and accurately quantify stress as in the constant load test method for stress corrosion testing. The present invention relates to a load loading device for a constant load test device suitable for cases where it is necessary to perform a large number of tests.

[Conventional technology]

As described in Japanese Patent Application Laid-Open No. 60-73433, the conventional device installs a hydraulic generator, obtains pressure oil from the generator, and installs a hydraulic motor that outputs rotational driving force. A method was adopted in which a lifting nut was rotated to move the crosshead up and down, and a load was applied to a constant load testing device installed on a table.

A method is also known in which a screw shaft is manually rotated, a crosshead is moved up and down, and a load is applied to a constant load testing device set on a table.

[Problem to be solved by the invention]

In any of the above conventional techniques, the structure was not such that the screws at both ends of the test piece in the constant load test device could be adjusted and fixed while the constant load test device was placed on the load test device. Even if a desired load was applied to the device and maintained, it was not possible to accurately apply that load to the test piece built into the constant load test device.

In other words, in order to apply the load set in a conventional constant load test device to the test piece built inside,
For example, use a temporary setting jig with a U-shaped cross section and an adjustment screw in the axial direction to fix the spring seat of the constant load test device during setup, and then remove the constant load test device from the load loading device once. The distance L between the fixed spring seats was measured, and then the test piece was temporarily set and the screws at both ends of the test piece were adjusted to make the distance L again.

Therefore, for example, even if the load of the test equipment itself can be accurately measured and the interval L can be reproduced after setting the test pieces, it is not guaranteed that the load at the time of measurement will be maintained accurately even after setting the test pieces. ,especially,
If the screws at both ends of the specimen are not tightened enough,
When the temporary setting jig was removed, the interval would become wider than L, and there was a high possibility that the error in load setting would increase.

Therefore, if it is thought that an error has occurred,
The above process must be repeated from the beginning,
It was inefficient.

In material tests, especially stress corrosion tests, the acquired data must be reliable because the tests are performed with slightly different stress values. The accuracy of the constant load test equipment affects the set load in stress corrosion tests, and if the accuracy of the constant load test equipment is poor, the accuracy of the load applied to the test piece will be poor, and the reliability of the acquired data will be low. means.

On the other hand, since test pieces have manufacturing tolerances and load loads vary to some extent, it is difficult to judge the characteristics of the material based on data obtained from a single stress test piece. Therefore, a large number of specimens are tested under the same test conditions and the results are statistically processed to determine the properties of the material.

As described above, in material testing where it is important to increase the number of test pieces to a certain extent, variations in set loads are a major negative factor. In addition, since the load-bearing device is large-scale, a lot of time is required for preparation and adjustment work. For example, when verifying the load of a material testing device in the reactor water environment of a nuclear plant, If it seems like it takes a long time to configure or reconfigure,
This is undesirable as it may lead to radiation exposure to the person taking the measurements.

An object of the present invention is to provide a load loading device for a constant load test device that can accurately and quickly set a predetermined load.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a constant load test device that applies a constant load to a test piece by adjusting the distance between an upper nut and a lower nut that are adjustable from the outside in the axial direction of a built-in test piece. The drive section that gives the same load, the support plate on which the constant load test device is placed and supports it against the load from the drive section, the calibrator that measures the load applied from the drive section, and the top of the constant load test device are precisely opposed to each other. In the load loading device of the constant load test device, the support plate has an opening for adjusting and setting the load to be applied to the test piece by adjusting the lower nut. This paper proposes a load-bearing device for a constant-load test device that is located in the center of the part where the load is placed.

The present invention also proposes a load loading device for a constant load test device, in which the compression plate is provided with a nut rotation stopper that prevents the upper nut that fixes the upper part of the test piece built into the constant load test device from slipping. .

[Effect]

In the present invention, the opening of the support plate is provided at the center so as to coincide with the center of the constant load testing device placed there. By inserting an adjustment tool into this opening, it is possible to easily set the load of the test piece built into the test device. In addition, since the load can be directly set without removing the constant load test device from the load application device, the working time can be significantly shortened and the fluctuation range of the load setting value can be reduced. Furthermore, the set load can be confirmed visually using the displacement meter of the detector, and there is no fear of underloading or overloading the constant load testing device, and the operability is good.

〔Example〕

Prior to describing embodiments of the present invention, the structure of a constant load testing device will be briefly described.

FIG. 13 is a longitudinal cross-sectional view showing the overall structure of the constant load test device. The constant load test device 12 includes a bell spring 21 connected in series and two sets of bell springs 21.
a, 21b for exposing the test piece 15 to the test environment; a pair of spring seats 20a, 20b that sandwich the bell spring 21 from both ends and grip the ends of the test piece 15;
Tightening nut 24 to keep the 0 interval at a predetermined value
a, 24b, and a pair of sleeves 28a, 28b whose load direction is aligned with the axial direction of the test piece 15.
a pair of connecting spring seats 22a that connect the sleeve 28 and the connecting guide 23 and receive one end of the plate spring 21;
22b, scattering prevention covers 26a, 26b that prevent scattering when the test piece 15 breaks, and set screws 25a, 2 that fix the scattering prevention cover 26 to the spring seat 20.
It consists of 5b. The present invention relates to a load loading device that sets a predetermined load between the spring seats 20a and 20b of such a constant load loading testing device 12.

Next, a preferred embodiment of the present invention will be described with reference to FIGS. 1 to 12.

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of the load-bearing device of the constant-load test device according to the present invention together with the constant-load test device. In the figure, 1 is a handle, 2 is a screw shaft that transmits the load, 3 is a holder for the screw shaft 2, 4 is a fixing plate that fixes the screw shaft 2 at the top, 5 is the overall support, and 6 is a support provided to the support 5. A guide plate that transmits the load to the annular load tester 7, 8 a dial gauge installed in the tester 7 to measure the applied load as a change, 9 a base for the tester, 10 prevents the tester 7 from lifting up. Shaft, 11 is a compression plate that transmits the load to the constant load test device, 12 is the constant load test device shown in FIG. 13, 13 is a base plate on which the constant load test device 12 is placed, 14 is a constant load via the base plate 13 A support plate supporting the test device 12, 15 is a constant load test device 1
2 is the built-in test piece, 16 is the overall support,
17 is a pressure plate inserted between the guide plate 6 and the tester 7, 18 is a rotation stopper for the holder 3, 19 is a nut rotation stopper attached to the compression plate 11, and 24b is a nut whose rotation is regulated by the rotation stopper 19. upper nut,
A lower nut 24a is tightened by a tool inserted through the hole 30 and applies a predetermined load to the test piece 15. As shown in FIGS. 4 and 5, the guide plate 6 has a cutout portion that engages with the support column 5, and moves up and down smoothly as the handle 1 rotates.

A feature of the present invention is that, as shown in FIGS. 2 and 3, an opening (hole) 30 for adjusting and setting the test piece 15 is located in the center of the portion of the support plate 14 on which the constant load test device 12 is placed. This is because we have established the following.

Another feature of the present invention is that FIGS.
As shown in the figure, a groove 31 is formed on the lower surface of the compression plate 11, and as shown in FIGS.
This is because a nut rotation stopper 19 having a pawl 27 that engages with the nut 19 is provided.

A method of applying a load to the constant load testing device 12 using a load applying device having such a configuration will be explained.
Shatterproof covers 26a and 26b shown in FIG.
, and then remove the constant load test device fixing bolt, which is not shown but is incorporated in place of the test piece. Next, the actual machine test piece 15 is inserted from the spring seat 20. Then, attach the upper nut 24b,
The lower nut 24a is left unattached.

In this state, the constant load test device 12 is placed on the base plate 13 shown in FIG. 1, but before that,
The center of the base plate 13 is aligned with that of the verification section 7 and the compression plate 11 to prevent eccentric loads from being applied to the constant load testing device 12. The constant load test device 12 placed on the base plate 13 is set at the center of the base plate 13 (support plate 14). This is to prevent torsional load from being applied to the constant load test device 12, as described above.

Here, as shown in FIG.
Attach. The upper nut 24b is sandwiched between the pawls 27, and the key portion 29 of the nut rotation stopper 19
is inserted into the groove 31 of the compression plate 11, so when tightening the lower nut 24a later, the upper nut 2
4b is prevented from idling.

Now, when the handle 1 is turned, the screw shaft 2 pushes down the guide plate 6. The load transmitted from the guide plate 6 to the tester 7 is finally transmitted to the constant load testing device 12 via the tester base 9, the compression plate 11, and the nut rotation stopper 19. Support plate 14
Use a material that has sufficient strength to withstand the above load and does not cause deflection. Therefore,
The load value applied to the constant load test device 12 appears as a displacement of the tester 7. This displacement is read by a dial gauge 8 provided at the center of the test. The load applied to each test piece 15 is converted into displacement in advance, and the load is gradually applied, and when the specified displacement is reached, the pressurization is stopped.

The procedure for setting the load around the lower part of the test piece is shown in Figure 12. Initially, it is in state A, but when a specified load is applied, it becomes state B. In this way, lower nut 2
Adjust the length of the upper threaded portion of the test piece that hangs over the upper nut 24b so that the length that allows the screw 4a to hang sufficiently is extended from the lower spring seat 20a. Next, with the load still applied, a box-shaped wrench or the like is inserted from below the opening 30 of the support plate 14 to attach the lower nut 24a to the test piece 15, completing the load setting. In this case, unlike the conventional example, it is possible to set the load without unloading the load of the constant load test device, so there is an effect that the fluctuation range of the set load can be reduced. Therefore,
The handle 1 is turned in the opposite direction to remove the load, and the constant load test device 12, on which the load has already been set, is removed from the base plate 13, and the work is completed.

As an application example, when verifying whether the load of the constant load test device 13 that has already been set is correct, in order to measure minute displacements, a new displacement dial gauge (not shown) is tested on the reference line of the test device base 9. Set it in a position close to the device 7, apply a load while watching the displacement dial gauge, and look for the point where the scale of the displacement dial gauge changes suddenly. At this point, the test piece 15 of the constant load test device 12 and the bell spring 21 were balanced. In other words, this is the load that was applied to the test piece, and the load can be easily verified.

Furthermore, even if the above test differs from the specified value,
Resetting can be done easily using the above procedure.

In particular, in the case of material testing, test results are often statistically processed and many test pieces are used, but with the present invention, it is possible to set loads with little variation, and the work can be done in a short time. Since this is possible, there are great advantages not only in terms of the reliability of the data obtained but also in terms of economics.

Note that the range of the load setting value of the constant load test device depends on the type of tester and the load value, but when using an annular tester as in this example, the set load is
In the range of 10 to 1000 kg, the variation in set load can be suppressed to approximately ±1%.

In addition, in the above example, a method was explained in which the screw shaft was rotated manually and a load was applied to a constant load test device placed on a table, but the constant load test device was installed on a table by a hydraulic motor. It will be obvious that the present invention can also be applied to a method of applying a load to the vehicle.

〔Effect of the invention〕

According to the present invention, there is provided a load loading device for a constant load test device that can accurately and quickly set a predetermined load on the constant load test device, and can easily verify and correct the already set load.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the load applying device of the constant load test device according to the present invention together with the constant load test device, FIG. 2 is a top view of the support plate, and FIG. A sectional view, Figure 4 is a top view of the guide plate, Figure 5 is a BB sectional view of Figure 4, Figure 6 is a top view of the compression plate, and Figure 7 is a CC cross section of Figure 6. figure,
Fig. 8 is a sectional view of the nut rotation stopper, Fig. 9 is a top view of the nut rotation stopper, and Fig. 10 is a bottom view of the nut rotation stopper.
FIG. 11 is a longitudinal cross-sectional view of the upper part of the test piece, FIG. 12 is a view showing the load setting procedure around the lower part of the test piece, and FIG. 13 is a longitudinal cross-sectional view of the constant load test apparatus. 1...Handle, 2...Screw shaft, 3...
Holder, 4... Fixed plate, 5... Support, 6... Guide plate, 7... Verifier, 8... Dial gauge, 9
...Base for tester, 10...Shaft, 11...
... Compression plate, 12 ... Constant load test device, 13 ... Base plate, 14 ... Support plate, 15 ... Test piece, 16
... Support, 17 ... Pressure plate, 18 ... Holder rotation stopper, 19 ... Nut rotation stopper, 20 ... Spring seat, 21 ... Distal spring, 22 ... Connection spring seat,
23...Connection guide, 24...Natsuto, 25...
Set screw, 26... Shatterproof cover, 27... Pawl, 28... Sleeve, 29... Key part, 30...
...hole, 31...groove.

Claims (1)

[Scope of Claims] 1. A drive unit that applies a load to a constant load testing device that is to apply a constant load to the test piece by adjusting the distance between an upper nut and a lower nut that are adjustable from the outside in the axial direction of a built-in test piece. , a support plate on which the constant load test device is placed and supported against the load from the drive section, a verification section that measures the load applied from the drive section, and the upper part of the constant load test device are accurately opposed to each other. In the load loading device of the constant load test device, the support plate has an opening for adjusting and setting the load to be applied to the test piece by adjusting the lower nut. A load-bearing device for a constant-load test device, characterized in that the load-bearing device is provided in the center of a part to be placed. 2. A constant load device according to claim 1, wherein the compression plate is provided with a nut stopper that prevents an upper nut that fixes the upper part of the test piece built into the constant load testing device from idling. Test equipment load bearing device.