Shelf life of Refractory Castables

[Saovicente]

Hello to all,

First, It is a great honor to express a thanks to all whom contribute to this great site. I have been popping in and out for the last year +, reading thru and thru many a thread on the various how-to of making (creating) a pizza oven, etc., and recently joined as a member.

I am now ready to take on the adventurous challenge in making my own pizza oven. For me, the first steps are to grasp an understanding of the various materials needed to make a pizza oven; from the foundation, support, slab, vermiculite insulation,hearth bricks, initial dome layer, insulation layer(s), and the finishing touches.

My plan is to make a 36? or 42? brick hearth with a castable dome, which could be a homebrew recipe or refractory (?pending? cost on refractory castable)

Which brings me to my first of many questions.

The shelf life of refractory castable:
After a long search, I found someone sitting (1 to 4 years?) on a few bags each of various refractory castable cement. Your thoughts on the various materials and if any are worthy of purchase based on its reputation and its long standing shelf life.

The products are: Each bag is/are 55 lbs

Tufshot ? LI (APGREEN)
WAM (Westmoreland Advanced Material)
EMT 60 or EMT CG70
KAOCRETE 250 C

My thanks for your thoughts,

Sandro

A Special thanks to David S for sharing his wise wisdom.

[david s]

Re: Shelf life of Refractory Castables

I think most manufacturers say the shelf life is around 12 months, however if it has been stored in moist conditions this could be even shorter. I make sure the stuff I get is less than 12 months otherwise there could be warranty issues. If the stuff is still loose in the bag then it should be ok. I'd be very wary of stuff that is 4 years old.

[Saovicente]

Re: Shelf life of Refractory Castables

David,

I met with the guy: The items were stacked on pallets and felt dry and workable (same as a few bags of concrete countertop mix, which had been sitting in a cool room for about 3 years. I have used the bags in the last 2-3 months to make bathroom tiles and the cement has performed well.

He is giving me a good deal on each bag, and of course I want to make sure the tensile strengthen, thermal heat capabilities are not compromised.

He has other items also to purchase: brinks, thermal blankets, boards (way to expensive), etc.

2nd item of shelf life:
He has two 1" 50sq ft boxes of Isofrax that has been sitting for around same time, and he is willing to sell them off for $50 a box. Any thoughts on the brand name and its shelf life?

I have added 2 pics for review: (1) castable. (2) Isofrax

PS: Appreciate any critique if any wording, phrase used is not correct. I am here to learn and ascend in all matters of a pizza oven construction and more.

I appreciate your thoughts,

Sandro

[david s]

Re: Shelf life of Refractory Castables

Isofrax is a brand that includes blanket, board and bulk fibre. I can't tell from the photo what it is, but being packaged that way it's probably board. It won't go off like the castable so should be ok, but it is brittle so check to see it is not damaged.

Regarding the castable I'd be asking to open a bag and remove a small amount to test. Mix it with water and see what it's like after 24 hrs. This is still no guarantee that the rest of it is ok though. Also look up the product on the net and print out the data sheet, then highlight the shelf life info and show it to the vendor.Like I said before if it is loose in the bag and not hard or lumpy it should be ok, you may be onto a good deal, but be wary. The paper bags of stuff I buy are never particularly well sealed so you may find some pretty easy to open.

[Saovicente]

Re: Shelf life of Refractory Castables

Thank you David,

I will go go back and ask for a sample.

PS: The two Isofrax boxes are blankets. I will purchase them asap as to not lose the deal.

Best Regards,

Sandro