The experimental determinations which were made had as a purpose the study of the peculiarities of the stator rubbers, regarding their behaviour when dealing with erosion wear, for the pumps with bolt. Three types of rubber were used, which were injected inside the stators, laboratory experiments were conducted, where there was used a device for the examination of rubber under erosion wear, made at SC UPETROM Ploiesti. The diagrams for the dissymmetry points were traced, according to the irregularity of the steel containers used during the experiment. The behaviour when being eroded includes an assessment of the length, width and depth of the fissure. The testing for erosion consists of measuring the depth of penetration of oil in the rubber, which a contact force is applied on. The experimental study of the well rubber was made in order to establish the working parameters for erosion wear research of the spiral screw pumps, used for crude oil recovery [1, 2].