MorphoSeal

In this type of connection, found in pumps for spraying various types of product (paint, petrol, etc.), the rods are often coated with hard chrome plating. This is commonly used for its exceptional anti-wear properties. However, it is made from chromium VI, which is carcinogenic and toxic to the environment. The aim of this thesis is therefore twofold: to reduce the probability of pump leakage in order to avoid the propagation of toxic products in the environment, and to replace the hard chromium coating with one that is more respectful of the environment and human health. To achieve this, an experimental bench was set up to quantify contact permeability. At the same time, the topography of the two parts was analyzed to measure wear volumes. The performance of hard chromium plating is thus compared with that of competing coatings. In order to make these studies usable for the study of the sealing of other similar contacts, a numerical model is developed. The aim of this model is to determine the permeability coefficient of a contact as a function of the roughness of the pins and seals. The approach used enables the leakage flux to be evaluated very quickly, while considering the impact of rod movement on fluid transport in the contact.