by Deepthi Pamadiparthi and Laurel Donoho, Frost and Sullivan

Frost & Sullivan estimates the total North American mechanical seals market revenues at $992.4.0 million in 2008. Figure 1 shows the revenue trend for the North American mechanical seals market for 2005-2015. In the current economic downturn, the mechanical seals market is expected to experience a growth rate decline until mid-2010, but is likely to grow to generate $1,287.2 million by 2015. (Note: North America is defined as the United States, Canada and Mexico for this research.)

Figure 1 Source: Frost & Sullivan

Key Market Drivers

Key issues expected to positively affect seal demand include:

  • Strong Environmental Protection Agency (EPA) guidelines and an intense need to reduce fugitive emissions in rotating equipment. Oil and gas, chemical, food and beverage, and pharmaceutical applications require superior sealing ability to prevent contamination of the end-product.
  • Customers worldwide are focused on improving overall equipment performance to reduce operational costs and productivity losses. Mechanical seals have helped reduce equipment downtime due to high performance.
  • Investments in the oil and gas sector are expected to continue beyond the current economic downturn, according to OPEC's forecasts.
  • Retrofits market opportunities will exist due to the aging plant population in the United States.
Return on Assets (ROA) and Total Cost of Ownership (TCO): The Future of Seals

While growth trends in the market are certainly of interest, expected future attributes of seals technology and monitoring are hot topics. The remaining comments focus on these key areas, including supply chain technology contributions, proactive and preventive maintenance and intelligent monitoring and support systems.

Technology Trends in Supply Chain

Mechanical seals form a crucial part of rotating equipment, since poor performance or failure results in yield loss. Incremental changes in the materials and sealing surface compositions of mechanical seals have addressed challenges such as dry running conditions and failures due to operator mishandling and various other failures. Suppliers of sealing surfaces have been consistently focusing on two major aspects: (a) improving the performance by employing coatings and (b) specific structuring on sliding surfaces.

A major factor contributing to seal failure is dry running; improving the performance of the sliding surface can drastically reduce these failures. Small grooves of special patterns are formed on these sliding surfaces and the grooves act as lubrication pockets during pump start-up or in the absence of adequate lubrication. This forms a thin film of lubrication, which reduces the initial friction coefficient on the surface and the energy consumption.

There have also been incremental innovations in improving the surface characteristics with coatings to prevent pump failure in dry running conditions or the handling of corrosive liquids. Diamond coatings and polycrystalline diamond coatings are being employed for seal rings used in high wear applications. These incremental changes in mechanical seal components have enhanced the performance of mechanical seals, aid in reducing energy consumption, improve the life of the seal, reduce the life cycle costs and decrease the risk of premature seal failure, thereby enhancing ROA and reducing TCO.

Reducing TCO: Preventive Maintenance and Condition Monitoring

Mechanical seal life can be enhanced by proper sizing for appropriate applications, operator awareness and proper employment of fluids per manufacturer specifications. Effective maintenance of rotary equipment also affects seal life. Preventive and proactive maintenance are two methods in which proper maintenance of the seal can be ensured. Preventive maintenance of the mechanical seal involves measuring discrepancies during operation through instrumentation such as pressure and temperature switches or transmitters, and other instrumentation devices. This reduces overall downtime costs.

Proactive maintenance monitors seal health and uses a multi-tier approach by providing information on equipment condition, intensity of discrepancy and severity of inconsistent performance. It may employ intelligent controls that can take necessary corrective action. Dual seals with intelligent support system are one example. These systems reduce the costs incurred in repair, production loss and process interruptions from intermittent pump or compressor failure.

End users also use condition monitoring to monitor the seal condition based on parameters such as seal face temperature or collapse of lubrication film so that appropriate measures are taken to solve the problem. One method of identifying seal life is measuring the lubrication film thickness. Two technologies help measure the seal's lubrication film thickness:

  1. A laser interferometer, which is restricted to laboratory applications
  2. Reflection of ultrasonic waves: the amplitude of reflected ultrasonic waves measures the degree of contact between seal faces and intensity of collapse of lubricating film. However, there have been several challenges in mounting the instrument without disturbing the seal design.

Figure 2 (Source: Frost & Sullivan)