The effect of the use of scrapers on the film heat transfer coefficient was investigated. Experimental runs were conducted in liquid-full, continuous-flow heat exchangers of commercial size, with a 6-in. ID and 6-ft length. Three test fluids were used: two petroleum lube fractions and corn syrup. Flow rates were varied from 0.8 to 5.8 gpm and the scraper speed from 0.5 to 25 rpm. The data collected were utilized in developing a design correlation in the laminar regime (Rer < 150). The correlation obtained for heating and cooling was Nu = 57 Ref0.059Rer0.113Pr0.063Visr−0.018, for 0.0016 < Ref < 9.23 and 0.0164 < Rer< 68.65.