How do you dry refractory?
Hold the temperature inside the wall tubes or steam drum for a period of 1 hour for every inch of the thickest refractory area required to be dried on the outside of the boiler (e.g., the largest wall box may have a depth of 5 in., requiring a hold time of 5 hours).
How long does refractory mortar take to dry?
If not cured completely, the material will crack due to the pressure caused by water evaporating within in the mortar. Allow a minimum of 7 to 10 days before heat is applied. Full curing times will vary with individual job conditions, sunlight, temperatures, and humidity.
Can you mix refractory cement with perlite?
1 part Furnace cement + 4 parts Perlite (This is by volume. For example, if you use ½ gallon of Furnace cement, you will need to purchase 2 gallons of Perlite.)
Why is my mortar crumbly?
Crumbling or failing mortar can be caused by a number of reasons: Failing mortar can usually be attributed to a lack of carbonation of the lime within the mortar meaning that the mortar will have little if any, strength.
Why is my thinset not drying?
Excessive Humidity If you live in a tropical environment or somewhere where the humidity is high, your thinset will take longer than the 72-hour maximum curing time given as an estimate by most manufacturers.
Are your refractory dryouts not delivering the required results?
As illustrated in the three examples above, refractory dryouts using the main burner have not been able to deliver the required results of a proper dryout schedule. The results of an improper dryout have led to refractory failures, equipment damage and increased monitoring requirements.
What is boiler refractory dry out procedure?
Boiler refractory dry out procedure. Boiler Refractory dry out is to ensure proper drying, curing of refractory applied on furnace and other components. The refractory usually undergoes considerable chemical changes, during initial heating.
Why consult the refractory manufacturer before installing the lining?
The refractory manufacturer should therefore always be consulted as to the proper refractory placement and curing temperatures in advance of the lining installation so that environmental controls can be initiated if necessary.
How to maintain the refractory baking and dry out cycle?
Keep open all the vent lines ( 100% open) on the boiler drum, top super heater header throughout the refractory dry out period. Refractory baking and dry out cycle requires very slow and controlled heating of refractory as recommended by the refractory manufacturers. Thermal stresses will be produced if heating rate is too rapid.