Solid polyurethane tire/wheel assembly

A solid industrial polyurethane tire where said polyurethane is prepared by reacting (A) a curative of 1,3-propane diol with a prepolymer of diphenylmethane-4,4'-diisocyanate and a polymeric polyol or (B) a curative complex of 4,4'-methylene dianiline and a salt selected from sodium chloride, sodium bromide, sodium iodide, sodium nitrite, lithium chloride, lithium bromide, lithium iodide, lithium nitrite and sodium cyanide, where said salt is first dispersed in a plasticizer selected from at least one of dioctyl phthalate, tetraethylene glycol di(2-ethylhexoate) and dibutoxyethoxyethyl formal, with a prepolymer of a diisocyanate selected from (1) diphenylmethane-4,4'-diisocyanate and (2) toluene diisocyanate with a polymeric polyether polyol;

• where said polymeric polyol has a molecular weight in the range of about 800 to about 2500 comprised of polypropylene ether glycol in the amount of (i) about 90 to about 100 weight percent when combination (A) is used, (ii) about 30 to about 80 weight percent when combination (B-1) is used or (iii) about 50 to about 100 weight percent when combination (B-2) is used, where the corresponding remainder of said polymeric polyol is selected from at least one of (a) a polyether ester selected from at least one of diethylene glycol, dipropylene glycol and dibutylene glycol ester of a dicarboxylic acid selected from at least one of adipic acid, isophthalic acid, phthalic acid and terephthalic acid and (b) at least one polyester polyol derived from a saturated hydrocarbon diol having 2 to 6 carbon atoms and a dicarboxylic acid selected from at least one of adipic, succinic, azelaic, phthalic and terephthalic acids, where the ratio of isocyanato groups to hydroxyl groups of said polymeric polyols is in the range of about 1.7/1 to about 2.3/1 and where the ratio of sum of hydroxyl groups of said 1,3-propane diol, if used, and amine groups of said 4,4'-methylene dianiline complex, if used, to the excess isocyanato groups over said polymeric polyol hydroxyl groups is in the range of about 0.8/1 to about 1.1/1, said tire characterized by (A) a polyurethane having a compression set of about 15 to about 45 percent determined by ASTM D-395 Method B and a Goodrich flex life of about 15 minutes or more (ASTM D-623 test modified by having a 437 psi load at 38.degree. C. starting temperature and a 0.15 inch stroke, or (B) capable of supporting an incrementally increased load up to at least about 7700 pounds for at least about 65 hours at a speed of about 3 miles per hour when said wheel assembly has a ground contacting tire portion with an outside diameter of about 15 inches, a width of about 5 inches and an inside diameter of about 11 inches adhered to a steel centered core.