R/S Soft Solids Tester (SST) for Foods, Cosmetics, Sealants, Gels, Pastes... The NEW R/S Soft Solids Tester is a controlled rate/controlled stress rotational rheometer featuring vane spindles designed to measure "lumpy" or viscoelastic materials. Features And Benefits Vane spindle geometry allows spindle insertion without compromising sample structure Easy-to-test method for materials with particulates, slurries, and stiff pastes Provides data that relates to viscoelastic characteristics such as yield stress, shear modulus (stiffness of material structure when intact) and creep Quantifies meaningful properties like wobbliness, sloppiness, consistency and texture Automated data analysis under PC control Rugged design for years of trouble-free operation in QC and R&D applications Can also be used with coaxial cylinders for flow curve analysis Optional Rheo200 software with Soft Solids Module allows you to program the R/S-SST and generate data such as yield point, shear modulus, creep and relaxation The Soft Solids Tester is IDEAL for testing difficult-to-measure materials such as Slurries, Gels and Suspensions and it provides Yield, Viscosity and Creep/Recovery data. The flow properties of these materials are not easily measured using traditional coaxial cylinder or cone & plate equipment. Vane spindle geometry provides a solution. The vane spindle is lowered into the test sample with minimal disruption. The test is easily run in the sample's original container. There are two significant Test Methods easily accomplished by the Soft Solids Tester: 1. Constant Rate Yield Test For Products Like: Stiff pastes, slurries, set gels, waxes Properties Measured:Yield Stress, Yield Strain, Modulus Test Description:This is a Constant Shear Rate Test. The vane is rotated at a constant low rotational rate and the Stress (torque) is measured against Time, Rotational Angle or Strain. Example Method for Mayonnaise:Constant Rotation at 0.2 rpm, 60 data points are taken in 60 seconds Typical Results Plot 2. The Creep/Recovery Test For Products Like:Gels, lumpy products like custard, gravy, sauces and jams Properties Measured:Instantaneous Strain, Viscous Creep, Elastic Recovery, Permanent Flow Test Description:This is a Constant Stress Test. The Stress (torque) is applied to the sample for a fixed time period, usually from one to five minutes. The degree of sample movement is recorded against time as Angular Displacement, Strain or Compliance. The Stress is removed and the Elastic Recovery and Permanent Flow is determined. Example Method for Fruit Preserves:Constant Stress of 1,250 Pa is applied over 120 seconds and 60 data points are taken. The stress is then removed and 60 data points are taken for another 120 seconds. Typical Results Plot