The glass reactor is sprayed with a high silicon content ceramic glaze on the surface of the low carbon steel tire, and is calcined at about 900 ° C to make the ceramic glaze close to the surface of the metal steel tire. Due to the different mechanical and physical properties of the two materials, the causes of the damage are also different. In general, the main reasons are as follows:
1. mechanical damage
The impact resistance of the glass is very poor. Any metal or hard object hitting the glass can cause damage to the enamel. Therefore, when using an enamel glass jug, any metal or hard material should be strictly prevented from falling into the kettle. In case of blockage, it must be dredged with a plastic rod. The cover should be covered during maintenance to prevent small pits or explosions on the surface of the molten slag.
2. The effect of working temperature
The glass reactor was baked and cooled at 900 degrees Celsius to bond the glass to the steel sheet. Since the linear expansion coefficient and elongation of the enamel glass are smaller than that of the steel sheet, the deformation of the glass after cooling is smaller than that of the steel sheet, and the compressive stress of the glass is caused by the constraint of the steel sheet. After the glass pot is completed, there is pre-stress in the glass and there is pre-stress in the steel sheet.
Since the pre-stress is related to the linear expansion coefficient and elongation, and the linear expansion coefficient and elongation are closely related to the temperature, the operating temperature of the glass-lined kettle has a great influence on the use of the glass-lined kettle. If the enamel exceeds its applied stress due to excessive temperature changes, the enamel will be destroyed. Therefore, the glass pot is extremely prone to explosion under hot and cold conditions.
When the feed temperature is too different from the temperature of the kettle body, too much steam during heating and too fast cooling may cause porcelain explosion. Therefore, when using the glass pot, slowly rise and cool, even, graded cooling.
3. the role of external forces
When carrying the glass reactor, only the cans are allowed to be stressed (referring to non-packaging), rolling and crowbars are not allowed to avoid vibration and collision, and it is strictly prohibited to apply stress to consumables such as pipe clamps and clamps.
Under certain conditions, the device is suitable for indoor storage. When storing the equipment outdoors, pay attention to cover and avoid bumping objects, sunlight and rain. During winter storage, special care should be taken to check for water in the tank and thermowell to avoid frostbite. For reactors or polymerizers with mechanical seals, the seals should be doubled and kept clean.
4. Machining stress damage
During the autoclave processing, a large amount of internal stress is generated due to steam drum, stamping, welding, and the like. If these stresses are not completely eliminated, the enamel autoclave will explode. This type of injury usually occurs in the first three months after surgery, so heat treatment or aging treatment of the embryo body can prevent porcelain explosion.
5. electrostatic piercing
The liquid containing the suspended matter is stirred in a glass jug, and the suspended matter is strongly rubbed against the tannin. At the same time, the suspended matter itself generates friction and generates a large amount of static electricity. High static charge has a strong puncture effect on enamel, leading to pitting of enamel. Therefore, the stirring speed should not be too fast.
6. Hydrogen evolution
After a period of use, the outer shell of the glass jug will scale and rust. If the acid scale remover is used to remove the dirt or the coolant in the jacket is acidic, hydrogen evolution corrosion occurs in the metal (fe + 2hci = fec12 + h2o). Some hydrogen atoms diffuse into the metal pores and combine to form hydrogen. Due to the compactness of the enamel, these H atoms cannot diffuse outward, so when H2 accumulates to a certain extent. When a certain force is formed, the glass will break.
Therefore, when pickling is used for cleaning and scaling, a buffer must be added. If the value of the glass pot is high or difficult to replace, or even corrosion perforation occurs, a high-quality cleaning agent with a low corrosion rate must be used to avoid serious consequences caused by improper cleaning operation.
7. Unqualified base material
In order to reduce the cost, some factories use Q235 steel instead of the embryo body, which directly leads to the gasification of carbon and sulfur in the steel during the enamel process, and forms a large number of bubbles in the glass layer and the matrix and inside.