(1) The sample holder falls off
Careful observation of the structure of the thermogravimetric analyzer（TGA)
shows that there is a high-temperature-resistant and corrosion-resistant colloidal material, that is, an adhesive, between the tripod of the balance and the thermocouple. Detachment of the sample is usually due to failure of the adhesive. Although the material used in the adhesive is resistant to high temperatures, when the test sample is cycled or maintained at high temperature (above 600°C) for a long time, the adhesive will also be destroyed, causing the sample holder to fall off, and the sample crucible cannot be placed on the holder smoothly On the other hand, the service life of the heating wire will be shortened. Therefore, in order to effectively protect the sample holder, long-term high-temperature operation and use of the instrument should be avoided as much as possible.
(2) The sample holder is broken or the sample crucible is buckled on the holder.
During the use of the thermogravimetric analyzer（TGA), sometimes the sample holder breaks or the sample crucible gets stuck on the sample holder. The analysis of this phenomenon shows that when the gas is fed in front of the sample, if the flow rate of the gas is too large and cannot be exported in time, the pressure in the balance furnace will rise instantaneously.
If the furnace cover of the thermogravimetric analyzer（TGA) balance is opened at this time, the furnace cover will burst due to pressure relief or the sample holder will vibrate violently, causing the sample holder to break. If the crucible of the last sample test is forgotten, the strong air flow will overturn the sample crucible, causing it to buckle upside down on the stand.
The residue of the thermogravimetric analyzer（TGA) sample will also fall into the furnace of the balance, thereby affecting the measurement of the balance, and the residue is not easy to clean. At this time, professional engineers must be hired for maintenance.
The reason may be: after the main valve of the gas cylinder is closed after each sample measurement, in order to discharge the residual gas out of the furnace in time, the gas switch of the instrument is often opened, and the pressure reducing valve of the gas cylinder of the thermogravimetric analyzer （TGA) is opened very large, so that Gas out as soon as possible. After the pointer of the pressure reducing valve returns to zero, close the gas cylinder pressure reducing valve and the gas control switch of the instrument.
If you forget to close the pressure reducing valve of the gas cylinder and the gas control switch of the instrument after the sample test of the thermogravimetric analyzer（TGA) is completed, the air flow will not be controlled by the pressure reducing valve and the gas switch of the instrument when the main valve of the gas cylinder is opened during the next sample test. Controlled, excessive air flow is generated instantaneously, causing the furnace cover to burst or the sample holder to break.
In addition, if the gas flow of the thermogravimetric analyzer（TGA) itself is too large (140Ml/min), it will also cause a similar phenomenon. Therefore, before setting out each time, the support must be raised first, and then the furnace cover should be opened to reduce the gas pressure to protect the balance and support.