Durante varias décadas, los soportes de los cojinetes de las poleas transportadoras estuvieron protegidos del medio ambiente con métodos de sellado tipo laberinto. Si bien ha habido iteraciones a lo largo de los años, fundamentalmente adoptan un enfoque de sellado de "camino tortuoso lleno de grasa".

DASH Engineering son consultores de rodamientos imparciales e independientes ubicados en Perth, Australia Occidental, y se especializan en análisis de fallas de rodamientos. Después de haber realizado cientos de investigaciones sobre fallas de poleas transportadoras, atribuidas la mayoría de las fallas al ingreso de contaminación, DASH Engineering ha demostrado que los métodos de sellado tradicionales y el estándar de la industria, la 'Solución de tres barreras', no son efectivos para prevenir el ingreso de suciedad y agua al rodamiento. alojamiento. Pruebas independientes y numerosos estudios de casos han demostrado que la grasa actúa como portador de contaminación en lugar de como barrera. Además, los métodos de sellado tradicionales no se adaptan a la desalineación y la flotación que se requieren en las aplicaciones de poleas transportadoras.

…”este es un cambio radical en Minería” – Gerente-Gestión de Activos

With the overwhelming majority of DASH Engineering failure reports recommending to ‘review sealing methods’, it became evident that there was no other effective method of keeping contamination out of the bearing housing, sparking the development of the SAPO® Seal.

…” savings will be comparable to AutoHaul” – Site-based Project Manager

The Self-Aligning Pressurised Oil (SAPO®) Seal is a patented, engineered sealing solution that will accommodate misalignment requirements without compromising on sealing effectiveness. Furthermore, SAPO® Seals are fully maintainable, monitorable and predictable providing peace of mind to the end user.

In order to effectively maintain positive sealing, the SAPO® Seal is designed to float with respect to the housing as well as remain parallel with the shaft. This unique design allows for articulation to the allowable misalignment limits of spherical roller bearings.

The SAPO® Seal does not rely on grease as a sealing medium. Positive pressure oil is used to ensure the oil seal lips remain lubricated and simultaneously captures fine dust particles. Regular oil sampling and flushing ensures seal performance is monitored and maintained throughout its life.

…” we need to make them all like this” – Fitter-Site Installation Team

Current plummer block sealing methods tend to damage shafts – often damaged beyond repair. SAPO® Seals eliminate this problem with a simple solution. The units are designed to run on wear sleeves to prevent abrasive damage to shafts.

SAPO® Seals are fully maintainable, monitorable and predictable with state-of-the-art intra-bearing housing endoscopic monitoring via the SAPO® Scope. Maintenance personnel are able to visually monitor the housing cavity for contamination ingress and excessive bearing greasing whilst the machine is fully operational. This type of visual monitoring is truly unique in providing peace of mind and removes any doubt in regard to contamination ingress.

SAPO® Seals can also be used to assist with pulley alignment during installation, reducing set-up time and risk, increasing safety and efficiency. A simple yet effective technique allows for on-the-go visual alignment guidance and final quality assurance checks to remove any doubt during pulley install.

…” most significant benefit will be that we finally have effective, multi-level monitoring of bearing condition as risk mitigation against unplanned failures” – Site Engineer

Key facts

The implementation of SAPO® Seals have enabled multiple critical pulleys to achieve upwards of two times the previous mean time between failure (MTBF) across Australia’s Pilbara iron ore operations. Case studies on high grade iron ore conveyor systems have resulted in:

• increased production

• elimination of unplanned downtime

• cost savings in the order of tens of millions of dollars

Rolling stats

SAPO® Seals allow clients to switch from time-based maintenance techniques to condition-based maintenance methods.

Case Studies

A large 2m diameter pulley weighing approximately 28 tonnes on a system conveying bulk material across the Pilbara was changed out every six months due to repeated rapid

contamination ingress related failures. The site team decided to make the switch to SAPO® Seals and have experienced reliability and predictability to another level.

Otra polea crítica en un sistema transportador de carga de barcos estaba experimentando problemas de confiabilidad que causaron tiempos de inactividad no planificados que costaron cientos de miles de dólares. La polea se equipó con sellos SAPO ®  en la siguiente oportunidad y ha estado funcionando de manera confiable desde el cambio.

La implementación de  los sellos SAPO ®  no requirió modificaciones a los soportes de rodamientos estándar tipo 'SD'.