Which type of cement do you use?
It is a common mistake to use refractory cement for all high temperature applications. Using the wrong type of cement can cause serious problems.
The chart below shows the maximum recommended temperatures based on the type of cement used. For example, if you need your brick to withstand 2000ºF, then you should use castable or high-temp mortar. If your project will be exposed to 1800°F, then you can use refractory mortar. Refractory mortar can not withstand as much heat as castable or high-temp mortar, so it is important to understand the differences between each type of cement.
I want to know what type of cement people are using to make refractory materials. I am currently using Portland cement in a 50/50 mix with lime. I primarily use it to make lids that fit over the top of burners and also make fire pots, which also get cemented together. It is working, but I am not very happy with it.
I have heard some people talk about fire clay, which they say is a much better medium for casting around the burners (because it can withstand higher temperatures). This sounds like something that would work well, but I haven’t tried it yet. Do you have any experience with both Portland cement and fire clay? Which one do you prefer and why?
I am interested in hearing from you about your experiences using these two materials. Please let me know which one you prefer and why. You can also include pictures in your comments if you have them available. Thank you!
Unfortunately, there is no easy way to determine the type of cement used in a given project. Nor is there any easy method for determining the presence or absence of refractory cement in a specific location. The only sure way to determine the presence or absence of refractory cement is to take samples and have them tested.
The standard test for refractory cement consists of two parts: The first part consists of placing a sample in a container which has been filled with water and then allowing the sample to dry out completely. If it dissolves completely, then it must be a standard cement. If it does not dissolve completely, then it must be a refractory cement.
The second part consists of adding an acid to the sample and observing its reaction over time. If it reacts with the acid, then it must be a standard cement. If it does not react with the acid, then it must be a refractory cement.
Have you ever heard of refractory cement? It is a special type of cement that has been designed to be extremely heat resistant. The high temperature tolerance of up to 2,700 degrees Fahrenheit makes it an ideal material for use in the construction of outdoor fireplaces, fire pits, pizza ovens and chimeneas.
A recent trend in the outdoor heating industry has been the popularity of fire bowls. Fire bowls are portable metal containers that have been pre-filled with a specially formulated refractory cement mix. The manufacturer will simply start a fire directly on top of this type of cement and then place the bowl in any outdoor setting.
The convenience factor is what makes this product so popular. All you have to do is light a fire and then sit back and enjoy your evening. You don’t have to worry about mixing up a batch of mortar or dealing with wet cement that has yet to cure. Everything has already been done for you so you can focus on having a good time with family and friends.
Refractory cement can be used for casting your own forge furnace, or just about anything else you would use castable refractory for.
I will use this material to make the bowl of my BBQ grill. This is a recipe I have used before and is pretty good:
3 parts fire clay
2 parts grog or pulverized firebrick (If you cant find these locally, you can substitute kitty litter that does not have any additives)
1 part portland cement (You don’t want “quick-dry” cement, it has additives that are bad in a high heat application)
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Fire clay can be found at pottery and ceramic supply houses. You can also substitute kitty litter for the grog if necessary. Portland cement is available at building supply stores.
Mix thoroughly, then add water until it will just hold its shape when squeezed in your hand. It should almost feel too wet to use, but if its too dry, everything will crack and fall apart! Press into place, then smooth out the edges with water. Let dry for several days before using. If you need to cast something small and intricate with this material, like say a door handle for your forge, make
refractory cement is a specially formulated cement with a high alumina content. The composition of this product is designed to withstand temperatures up to 2000°F. This product can be used for casting into custom designs, pouring into a mold, or for troweling onto surfaces to create a fireproof surface.
refractory cement can be used in several different applications. For wood-burning stoves, the cement can be used for repairing cracks and defects in the firebox. It can also be used for creating an air tight seal around flue pipe connections. When installing firebricks into the firebox of a wood stove, refractory mortar is recommended for greater strength and more heat resistance than regular Portland cement mortar.
refractory cement is also ideal for setting your firebrick when building your own masonry fireplace or pizza oven. It should cure for 72 hours before being heated to allow it to reach its maximum strength.
We would like to use refractory cement in a gasifier. We know that it is used for the kilns, but don’t know where to buy some. Can you help?
Answer: Refractory cement is used for casting in place linings inside of the kiln and it also used in the construction of firewood burning masonry heaters.
Here is a web site that has some information about purchasing refractory cement:
http://www.hottipscorp.com/refractory-cement.html
The above web site also gives some information about how to make your own refractory cement by mixing portland cement and fireclay.