This report describes two programmes of wear testing, planned by TRRL but carried out under contract by BHRA fluid engineering, Cranfield, Bedfordshire. Abrasive slurry was circulated through 38mm diameter pipe in a closed-loop test rig and the amount of wear was assessed by measuring the weight loss of short removable lengths. In the first programme (1979/1980) the slurry was varied to study the influence of velocity, concentration, particle size, and particle hardness on the wear of ordinary steel pipe. The following conclusions were reached: 1) over the range investigated (2 to 6m/s) wear varied to a power between the square and cube of velocity. 2) over the range investigated (5 to 15 per cent by volume) wear varied more or less linearly with concentration. 3) over the range investigated (0.015 to 1.5mm) wear varied more or less linearly with particle size. 4) emery (mohs hardness 8 to 9) produced a wear rate several times greater than that for silica sand (mohs hardness 6 to 7). in the second programme (1980/81) the operating conditions were kept constant (velocity 4m/s, 10 per cent slurry of 0.15mm emery) while 18 different pipe materials were compared. Most of them proved to be more resistant to wear than mild steel but no particular class was found markedly to outrank the others. Somewhat surprisingly the best four materials comprised one from each main category (metal, ceramic, rubber and plastics). an annotated bibliography of 60 papers on other pipeline wear work is given in appendix a. (Author/publisher)
Samenvatting