Can the front arch of the furnace be changed from refractory bricks to integrally built with refractory cement?
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I would like to ask all the masters, the company has a 15T coal-fired boiler. Recently, the front arch of the furnace has cracks and is in danger of collapse. It must be rebuilt. Can the refractory bricks be replaced by refractory cement? This post was last edited by ssbayf on 2008-3-6 07:37 ]
For the poster's question, please explain the specific model of the furnace. Here, I can say that the general ones can be changed. However, you must pay attention to the proportion of ingredients. The boilers used in my unit are all made of refractory concrete. But the proportion must be paid attention to, otherwise, it may not be as good as refractory bricks. The specific proportion, more professionally speaking, depends on what kind of coal you use, or what kind of fuel. For example, if you use Class II bituminous coal and Class I bituminous coal, the proportions used are different. I don't know if these can help you. Please tell me the specific situation and I will try my best to help solve it.
OK, anything is OK, it’s just a question of whether the price and lifespan are reasonable, but please note: Refractory bricks have generally been dried or sintered in the manufacturing plant, so when the boiler is started, it only takes a relatively short time to dry the refractory mud. ； For overall pouring, it depends on whether gas-hardening or hydraulic-hardening refractory materials are used to determine a reasonable oven program.
Yes, if refractory bricks are hard to find, refractory cement can be used as an emergency solution, but the construction is troublesome, the drying and oven time is long, and the service life is short.
Generally, concrete is poured as a whole, and the ingredients are not easy to control. If the mix is not good, the front arch will be in danger of burning out. It is recommended to use refractory bricks.
It is safe to use refractory bricks instead of arch bricks. The specific construction methods are as follows: 1. Make the mold ； 2. Choose the appropriate casting material ； 3. It is best to add heat-resistant steel bars to improve the arch strength. Note that the heat-resistant steel bars should be painted with asphalt or wrapped with tape to create expansion gaps. ； 4. Set up arch corner bricks and consider expansion joints. The expansion joints are determined according to the size of the arch. Generally, the front baking of a 15-ton furnace is about 2.5 meters, and the expansion joints are left about 10~15mm.
Castables can be used instead of refractory bricks, but heat-resistant steel wires should be added to the upper part of the arch.
Refractory cement can be used for pouring. Our unit uses this method.
It is best to add a certain amount of steel fiber or other additives that can increase strength.
It is better to use refractory bricks, and choose high-aluminum refractory bricks. If you use refractory concrete to build a plain arch, it is unreliable. If you add a heat-resistant frame but do not consider the cooling of the frame, it is useless. Because the temperature of the front arch is above 1200°, no matter how good the heat-resistant steel is, it has no strength and cannot support the front arch.
Yes, there are two issues to pay attention to: 1. The setting of expansion joints. 2. Prepare oven 1# hyjkl after pouring
The use of refractory cement is not allowed. It is possible to use refractory concrete. Of course, it can also be done using hot feed. When constructing refractory concrete, attention should be paid to the mix ratio and the proportion of water used should also be strictly used. The oven must be heated according to the requirements of refractory concrete to ensure that the moisture can be completely baked out, including natural water and combined water.
Refractory bricks instead of refractory cement? To be more precise, it is to change to refractory castable (refractory cement + castable). The ingredients of both are similar. Can be used instead.
It is possible, but it is better to use refractory bricks.