[en] The objective of this work focuses on the characterisation of friction and durability of self-lubricating polyurethane seals (HPU Lubric©) for an application such as pneumatic cylinders. For this purpose, a direct comparison will be made with a reference polyurethane (HPU Premium©). These two materials have the same properties with the only difference that HPU Lubric seal has self-lubricating properties. The polymers have been manufactured by the company Trygonal Iberia SL. The main motivation of the project is to develop the test procedure, as there are currently hardly any standard specifications for testing seals of this type, or for polymers in general, compared to those that exist for metals. To carry out the project, tribological characterisation tests were carried out firstly on the SRV tribometer, in which the pin-disc configuration was selected. Being the polyurethane the pin and the disc a chromium-plated steel. Afterwards, tests were carried out on the TESSA seal test bench to obtain the tribological properties of the component and thus, be able to compare these results with the ones obtained on the tribometer. Once the tests were completed, the results obtained were analysed by means of friction force, temperature, and pressure readings, making a comparison between the two materials. In addition, the specimens were analysed both, with the optical magnifying glass and with an optical microscope. The mass of the specimens was measured both, at the beginning and at the end of the test to analyse the mass loss. The results showed an improvement in the tribological properties of the HPU Lubric seals compared to the HPU Premium reference material. This difference was noticeable at higher temperatures, which, at higher temperatures obtained during the tests, i.e. the most extreme conditions for the seal, the self- lubrication of the material causes the seal to suffer less due to a continuous and consistent film that is created on the shaft, reducing both, the friction between the seal and the shaft, and the wear of the seal.

[eu] Lanaren helburu nagusia propietate auto lubrikatzaileak dituen zilindro pneumatikoetarako junta berri bat (HPU Lubric©) karakterizatzea da. Horretarako, erreferentziatzat hartutako poliuretanozko juntarekiko (HPU Premium©) diferentziak ikertuko dira. Bi materialek antzerako propietate mekanikoak dituzte, ezberdintasun batekin, HPU Premium materialak propietate auto lubrikatzaileak dituela. Juntak Trygonal Iberia SL enpresarengatik fabrikatuak izan dira. Proiektuaren motibazio nagusia entseguetarako prozedimendu bat sortzearena da, ez baitago ia arau estandarrik juntak entseiatzeko, ezta polimeroentzat orokorrean, metalekin daudenekin alderatuta. Proiektua aurrera eraman ahal izateko, karakterizazio tribologikorako entseguak egin dira, lehenik eta behin SRV tribometroan, non pin-diskoa konfigurazioarekin egin diren entseguak, pina polimeroa izanik eta diskoa altzairu kromatua. Ondoren, frikzio eta iraunkortasun probak egin ziren juntentzako TESSA entsegu bankuan. Bankuan egindako entseguen helburua konponentearen propietate tribologikoak lortzearena eta hauen emaitzak tribometroan lorturiko emaitzekin alderatzea da. Behin entseguak eginda, lortutako emaitzak analizatu dira, hau da, entseguetan lorturiko frikzio indarra, tenperatura eta presioaren datuak analizatu eta bi materialen arteko ezberdintasunak ikertu. Horretaz gain, saiakuntzak eginiko probetak mikroskopio optikoarekin zein lupa optikoaren analizatu egin dira. Probeten hasierako zein amaierako masak ere neurtu egin dira haien masa galerak analizatu ahal izateko. Emaitzetan ikusi da nola HPU Lubric juntak HPU Premium juntak baino jarrera hobea izan dutela propietate tribologikoetan. Hobekuntza hori gehien ikusi den momentua tenperatura altuak lortu direnean izan da, gero eta tenperatura altuagoa lortu, hau da, kondizio zakarrenak izan diren momentuetan, materialaren auto lubrikazio funtzioari esker juntak jasandako esfortzuak txikiagoak izan dira, honek ardatzean sorturiko etengabea eta trinkoa den film-ari esker frikzio indarra eta desgastea murrizten baititu.