(Daily Question) November 1, 2010

1. The temperature in the low-temperature range is difficult to control. 2. The air distribution is not ideal.

There is a dedicated furnace drying process, and this process must be followed. In the absence of a furnace drying process, it is recommended to install temporary lines to discharge the flue gas on-site or direct it to an incinerator. This is mainly due to the high amount of water vapor at low temperatures. Furthermore, in the low-temperature range, temporary thermocouples must be used to measure temperature; otherwise, if regular thermocouples are used, it is easy to damage the corundum sheath of those thermocouples.

Air distribution and temperature control are quite important! ! ! ! ! ! !

It is not possible to follow the furnace drying curve strictly.

The furnace drying process is intended solely to prevent dry cracking and damage to the furnace lining; it is necessary to carry out this drying before using the furnace in order to remove any water present inside the lining. This drying process takes several days and is carried out at different temperatures； Blowing with a fan before lighting the furnace is done to prevent excessive concentrations of flammable gases or fuel vapors inside the furnace, which could lead to an explosion upon ignition.

I just finished tending to the furnace, and now that I take a look, there are cracks in the furnace with a depth of 18 cm, distributed evenly! ! I used the curve provided by the manufacturer for installation, but there are still problems! ! Waiting has really tortured me! !

This post was last edited by xuehaier on 2010-11-3 at 16:04. It is recommended to bake for a longer time at lower temperatures! In this way, there will be less water vapor in the system later on, resulting in a better drying effect. If possible, it is also recommended to slow down the rate of temperature increase, and to extend the time at a constant temperature; this brings benefits, so everyone should give it a try. A special drying furnace pipeline with low-temperature heating and temporary thermocouples is required; without this, it becomes more challenging for the furnace operator to control the process, as carbon deposition can easily occur. Monitoring the lining installation process before drying the furnace, as well as ensuring that the lining materials are of quality, is crucial. If the lining is of poor quality or the installation is not done properly, the lining may peel off or develop large cracks, which can cause the furnace to malfunction. If these issues are avoided, then the drying process can be considered virtually foolproof.

We’re about to start working too; I really want to know about this issue with the prices

Pay special attention to the holding time at low temperatures: 1. At 150 degrees, the material must be held at that temperature for at least 8 hours to remove moisture from the surface of the lining. 2. At a constant temperature of 350 degrees, the process must last at least 8 hours to remove the free crystalline moisture from within the lining. If the constant temperature period is too short, or if the heating process is not smooth, the lining will be heated unevenly, which can easily lead to cracks in the lining; in severe cases, the lining may even come off.

Before heating the furnace, there is a specific heating curve that must be followed; the requirements may vary depending on the type of refractory material used. During operation, it is necessary to avoid burning at low air-to-fuel ratios in order to prevent the formation of carbon black. The heating rate can be controlled by adjusting the fuel gas volume and the gas-to-air ratio.