This paper is derived from the wear tests by level rotaing drum on which steel and four kinds of polpurethane test pieces are mounted. The tests were performed against solids/water mixtures in order to evaluate wear resistance of polyurethane elastmers in comparison with steel. The solids used were silica after grinding with sharp edges having the mean particle diameter of 4mm and 20mm respectively, and the term of tests were 104 days for small particles, 54 days for large particles.
　Through the tests, it was concluded that polyurethane elastmer can give a high wear resistance compared with steel, and it is strongly affected by particle size. The ratio of wear rate for steel to that for polyurethance elastmer, R, is ranging 2-12 for large particles, and 14-65 for small particles. The fluctuation in R for the solids with same mean size is mainly caused by the each properties amoung four kinds of polyurethane tested here, and the degree of fluctuation is not influenced by particle size.
　Furthermore, it was recognized that the wear test facility produced for trial can give the type of sliding abrason, which is locally close to that caused by sliding flow in the actual pipelines.