Worldwide sealing developer and manufacturer, Busak+Shamban, hasdeveloped a PDR Rotary Shaft Seal that prevents leakage and extendsseal life, reducing maintenance in Gearboxes on agriculturalmachinery.
The Combine PTO Gearbox provides power to many separatefunctions on agricultural machinery. With the static and dynamiceccentricity produced within some machinery designs, elastomericshaft seals can no longer provide reliable long-term sealing andneed frequent seal replacement, complicated by the engine oftenrequiring separation from the gearbox.
Sealing in PTO’s presents difficult challenges. The seal mustfunction with a high speed rotating shaft over a broad temperaturerange and be compatible with gearbox oil. Busak+Shamban engineerswere faced with designing a seal that ensures leak free operationover an extended service life. Their solution was an innovativedesign of PDR Rotary Shaft Seal incorporating a PTFE sealing lipwith a hydrodynamic pump back feature to cater for eccentricitywhile ensuring leak free operation and endurance.
Long term testing was undertaken at the customer’s andBusak+Shamban test facilities in the UK and North America. Thisincluded a 1,000-hour back-to-back comparison at temperatures from-35°C to +95°C against the elastomer seal currently used in theapplication, with intermittent pressure spikes and stop-startcycles.
Under these arduous test conditions, the PDR seals wereleak-free for the majority of the test, with a maximum leakage of0.007 grams per hour under the most extreme conditions. Incomparison, the elastomer seals continuously leaked throughout thetest at the rate of between 4 grams and 10 grams per hour.
To download our Turcon Rotary Shaft Seals catalogue please seethe Download Area of the website.