The settling velocity of solids in fluids is an important factor in fluid mechanics and process engineering. For example, the settling velocity is the decisive factor when planning sedimentation tanks for water treatment.
HM 135 contains two transparent cylinders for comparative examinations. The two cylinders enable comparing the influence of the sphere diameter, sphere density and different fluids on the settling velocity. Guide tubes in the cover of the two cylinders enable safe insertion of the sphere. Two O-rings per cylinder mark the measuring section. At the lower end of the cylinder there is a sluice through which the spheres can be removed again without significant loss of fluid.
A stopwatch measures the sedimentation time. Two areometers with different measuring ranges enable the determination of the fluid densities.