S. C. Dey & Co. Offers Capillary Rehometer or Melt Viscosity Tester. S. C. Dey & Co. Manufactures testing instrument for Material & Petroleum Testing. The Capillary Rehometer or Melt Viscosity Tester is used to determine polymer melt viscosity. It is a constant rate type instrument. It incorporates tool steel made Barrel or Cylinder.