Back to results
US 4,071,593 AGranted
Process for making a pitch impregnated, cold molded refractory article
AssigneeGeneral Refractories Company
InventorsGrant M. Farrington, J. Donald Harris, Alfred H. Foessel
Life of this patent
Estimating the term…
Abstract
A process is described for making shaped refractories by impregnating cold pitch-bonded shaped refractories with a liquid composition comprising hot pitch.
Claims8
A method for making a shaped refractory article comprising the steps of:
- a. preparing a refractory molding mix by blending particulate refractory material with 3.0% to 8.0% by weight of a binder composition comprising:
- i. 10% to 40% by weight pitch;
- ii. 25% to 80% by weight of an aqueous solution of a water-soluble resin, which solution contains from 40% to 60% by weight of the watersoluble resin;
- and
- iii. 10% to 35% by weight of an organic solvent solution of a thermosetting polymer, which solution contains from 60% to 100% by weight of the thermosetting polymer;
- b. shaping the refractory molding composition into a shaped refractory article at room temperature;
- c. heating the shaped article to a temperature in the range of from about 200.degree. F to about 1,000.degree. F to form a cold pitch bonded shaped article;
- and (d) impregnating the cold pitch bonded shaped article under vacuum with a liquid impregnation medium containing a material selected from the group consisting of coal tar pitch, petroleum pitch, and mixtures thereof.
5 more elements
A method for making a shaped refractory article comprising the steps of:
- a. preparing a refractory molding mix by blending 92% to 97% by weight of a particular refractory material with 3.0% to 8.0% by weight of a binder composition comprising:
- i. 10% to 40% by weight pitch;
- ii. 25% to 80% by weight of an aqueous solution containing from 40% to 60% by weight of ammonium or metal lignosulfonate or a urea-formaldehyde resin;
- and
- iii. 10% to 35% by weight of an organic solvent solution containing 60% to 100% of an alkyd resin;
- b. shaping the refractory molding composition into a shaped refractory article at room temperature;
- c. heating the shaped refractory article to a temperature in the range of from 200.degree. F to 1000.degree. F to form a cold pitch bonded shaped article;
- d. placing the heated shaped refractory article under vacuum for at least about 6 minutes;
- and
- e. impregnating the heated shaped refractory article under vacuum for at least about 5 minutes with a liquid binding impregnation medium comprising pitch under pressure.
7 more elements
Dependencies are inferred from the claim text.