TTO-KOK seals: advanced technology and reliable materials

The roadblock for rotating shaft is an indispensable component in any mechanical equipment that works with lubrication and is an element whose design and material be chosen with great care to ensure a correct use and long life. The seals are manufactured following modern and with materials of reliability techniques to guarantee fully all the requirements in use.

The retén TTO-KOK, which sells the company Euro bearings spain, S.L., is mainly constituted by a metal stand, which is usually sheet steel or stainless steel, a garter spring steel C72 phosphated (standard) or stainless steel AISI 302 (for acid and water) and a lip of retentionan element which ensures tightness by direct contact, which should be in the limits lower potential to secure a moderate friction and minimize the heat generated, to ensure that it retains its properties over a long period of time. TTO-KOK checkpoints also consist of an elastomer, depending on your application will have characteristics or other. The NBR, i.e. elastomer based on nitrílica, is of general use due to its high resistance to mineral and vegetable oils, abrasion, bending and the swelling. It may be also indicated for inorganic, alkaline and acidic compounds in concentration and not elevated temperature. The VMQ, elastomer based on silicota, has properties físicomecánicas lower than other types (resistance to breakage and laceration and lengthening) but has a very low permanent deformation and a very low coefficient of friction in some applications it is of extreme importance. It has good resistance to mineral oils but not gasoline, acids and chlorinated hydrocarbons. Finally, the FPM or elastomer fluorocarbon-based account with good physical properties at high temperature (with tips up to + 250 ° c). In addition, it resists oils, fuels, solvents and chemical agents in general. Not recommended for use in the presence of esters, ketones or amines.

For optimal use of checkpoints, Euro Bearings Spain, S.L. recommends that the surface of the shaft in the area of friction of the lip must be polished according to h11. The degree of finish and the hardness of the zone of retention are key factors in benefits and duration of the catch. Broadly, the minimum hardness should be around 45 HRC, for peripheral speeds of 3 to 4 m/s, while for higher speeds, we must overcome the 55 HRC. Another aspect to consider is the seat. The cylindrical cavity must be finished according to ISAH8 with viseles of roughly 1 mm to 5-10.

According to Euro Bearings Spain, in the construction phase, it is necessary to ensure the maximum concentricidad of the axis in relation to the seat. Any eccentricity between them causes a solidification of the lip of withholding resulting in an increase in temperature that is going to join the work and/or to the environment. Finally, the company emphasizes the decentring, which occurs when the axis of the rotation axis does not perfectly match the axis of rotation.