JPS5977304A - Structure for preventing breakdown of high temperature strain gage - Google Patents

Abstract

PURPOSE:To prevent the breakdown of a strain gage, by providing a separating material, which has small elastic modulus and is thermally decomposed when a muddy state heat insulator is hardened, between the muddy state heat insulator and the strain gage. CONSTITUTION:A lead wire 3 of a strain gage 1, which is attached to a structure body 2, is fixed by stainless steel foils 4. Then, a separating material 5 such as silicone rubber is applied. After the material is hardened, a muddy state heat insulator 6 and brick shaped heat insulators 7 are applied. Even though the temperature of the structure body 2 is increased and the heat insulator 6 are hardened under this state, the separating material 5 alleviates a harmful force. When the temperature is further increased and the heat insulator 6 is completely hardened, the separating material 5 is decomposed at a high temperature. A gap is formed between the heat insulator 6 and the strain gage 1, and the application of the harmful force on the strain gage is prevented.

Description

[Detailed Description of the Invention] This invention &j Prevents damage caused by thermal stress in the heat insulation ridge of a stone gauge used for stress measurement of high-temperature structures! p
Regarding construction.

When the stress m1 of a high-temperature structure whose surface is covered with a heat insulating material, such as parts of a steam turbine, is constant, it is possible to install a strong structure, and the surface is covered with a mud-like heat insulating material (with some fluidity). This heat insulating material exhibits complex deformation behavior during the curing process at elevated temperatures, and exerts harmful force on the strain gauges and their leads and wires that are fixed to the structure by groove and groove welding. As a result, there have been cases where a weak part, such as the connection between the gauge and the lead wire, breaks, making measurements impossible.

This sluice gate was created in view of the above, and by interposing a separating material with a small Ii'tl property coefficient between the muddy insulation material and the strain gauge, which thermally decomposes at least when the muddy insulation material hardens, It prevents damage to the strength gauge by slowing down the harmful forces generated during the hardening process of the mud-type insulation material, and when the insulation material hardens, a void is formed between the insulation material and the strength gauge, and harmful forces applied from the outside are prevented. It is characterized by protecting strong gear by insulating force.
There is C.

Embodiment 7 of the present invention will be described below with reference to Figure 1. Figure 1 shows the state in which a strain gauge is formed by cutting off a strain gauge.

The lead wire 3 is attached to the structure 2 as the object to be measured by welding, and the lead wire 3 is fixed with a stainless steel eraser 4 which is welded at the same time. After this, glue 5v of silicone rubber, etc. Wipe it and wait for it to harden.

/ 1st edition 1': In November, harmful t (power of 4 molars) is applied when applying maintenance materials (for example, when planting seedlings with Ic). Fig. 2 (Susu! Range 1 -1-)
1 detachment 1't 5? 1. Add 200% hardened PK, 724g thick A6 and brick-shaped heat insulating material 7. The state is as follows.

・=〇 shape, structure 2σ) temperature is "Niri", mud 4. I, the insulation material 6 is hard (2 start, it's a bad power): release 4 [-4
-Yo 5 to fr Otsu. However, since the material 5 makes a small cut ^1, the harmful force is transmitted in a relaxed manner. As the temperature rises further, the silicone rubber 5 decomposes at high temperatures and creates a gap between the heat insulating layer 6 and the range 1. 1. Prevent the stress caused by the heat disparity between the muddy insulation material and the cut material due to the recirculation of one material, and the application of harmful force to the strain gauge. In heat insulating materials that cannot follow temperature changes, the effect of stress insulation by voids is great.

In this example, silicone rubber was used as the cutting material, but it is also possible to use other materials such as epoxy resin, which have a small amount of elasticity and are thermally decomposed at high temperatures. 5+C Harmful force generated during hardening! - Due to the relaxation and thermal recovery of the structure of the seventh group, Ren,
Since the difference in thermal expansion between the spoiled material m1 and the cut pass material insulates the stress on the cows, it has the effect of preventing the strain gauge from breaking.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a condition in which a cut-out material is applied to a strain gauge, and FIG. 1...Strain gauge, 2...Structure, 5...Separation material, 6...Mud-like heat insulating material, 7...Brick-like g?
Ren material.

Claims (1)

[Claims] A strain gauge attached to an object to be measured is covered with a mud-like heat insulating material.
Sunagawa prevention structure for high-temperature strain gauges characterized by interposing a separation material that thermally decomposes when the deep material hardens.