Author: Tynan Carroll is Global Marketing Manager within the IDEX Sealing Solutions Group, which encompasses FTL Technology as well as the Precision Polymer Engineering (PPE) and Novotema brands.

Large bore diesel and gas engines (above and beyond 1000KW – equivalent to 60 liter capacity) are designed to deliver extended periods of runtime with minimal disruption, in industries where continual and risk-free performance is critical. Engineers charged with specifying products, such as seals and O-rings, must consider proven performance as the key benchmark during testing and procurement processes, to ensure engine stability and uptime are maximized. For sealing materials in particular, important performance requirements include the ability to withstand a broad range of temperatures, chemical exposure and the abrasive nature of continual operation.  

If not correctly selected to meet these operating conditions, failure can occur unexpectedly leading to downtime that can incur severe implications for the operating company, such as increased maintenance and downtime costs. Therefore sealing solutions must be considered carefully before they are implemented into any engine given that failure poses a significant threat.

This paper looks specifically at seals used in cooling water pumps that stabilise engine temperature during operation – perhaps the most critical seal in any large bore engine. It will explore that finding a custom seal, designed specifically to the exact properties of the cooling water pump should be the key concern of any design engineer when undergoing product qualification and selection processes.

Cooling Water Pumps and the Importance of Oil Seals

Cooling water pumps deliver the cooling essential for engine stability, without which the engine would overheat and breakdown. Commonly within these pumps a single elastomer seal will isolate the coolant from the lubricating oil within the engine. Leakage can be catastrophic to the pump, potentially leading to costly repair or maintenance work, and even total engine failure. It therefore becomes clear that cooling water pump seals require a high performing material that can meet the demands of rigorous and continual operation in challenging environments to avoid these costly pitfalls.

Achieving Endurance and Longevity with a Custom Solution

Companies can seek guidance to ensure that the design process for water cooling pump seals will have included all functional requirements necessary to deliver on-going and risk free service. Considerations will not only include material selection, but also the dynamics of the primary sealing lip and how this can be manufactured to withstand specific environmental factors. This will help to customize the seal design to ensure the lip is optimized for sealing efficiency through seamless integration with the internal pump dimensions. Seals can then be supplied with the sealing lips pre-formed to suit the dynamic running surface diameter.

The Benefits of a Custom Seal

There are many different types of sealing products available that present manufacturers with a cost effective and quick solution. However, given differing operating parameters, designs and reliability requirements, there is a strong case to be argued for embracing a customized and high performance PTFE sealing solution to withstand the extremities encountered within high horsepower engine operation. Although this may present a more expensive solution initially, it has been proven that the total cost of ownership of the seal and pump will be significantly reduced due to extended lifetime, as will the consequential reduction in replacement cycles.

Water pump oil seals that have been manufactured and pressed to the exact dimension requirements of the water pump, and made from high performance and quality tested PTFE materials, offer the potential for extended operational lifetime, potentially increasing seal life from 500 hours to 20,000 hours. Customized designed material technology and manufacturing processes are proven to deliver reliable and consistent performance over extended periods, providing benefits such as extended service intervals, minimized early life failures, reduced warranty claims, increased overall engine availability and virtually 100% universal chemical resistance.

For more information about how to improve the integrity of your seals within cooling water pumps, contact FTL Technology and request a full copy of our whitepaper titled Challenges and risks with large bore engine cooling water pumps versus cost effective sealing solutions: www.ftl.technology. Alternatively, call us on 0113 252 1061 and ask to speak directly to one of our experts first hand about your specific challenges.