New John Crane Seal Range Provides Improved Performance on Non-Turbo Applications

A new range of non-contacting mechanical seals launched by John Crane greatly improves seal performance on pump applications by reducing operational costs, enhancing reliability, increasing safety and also extending seal life. Designed for non-turbo, large–bore rotating equipment applications the new Type 2800X dual seals feature patented new technology that provides environmentally-friendly and emission-free sealing.

The 2800X seals have been created for use in a wide variety of performance-critical applications. These include the processing of extremely pure materials where no contamination is permissible, the use of reactive or temperature-sensitive media where local process ‘hot spots’ can cause unwanted chemical reactions, cold applications such as ammonia processing, and air/oxygen-sensitive processes where unwanted oxidation reactions could occur.

The seals feature spiral grooves machined into the mating ring faces of the seal heads. As the pump shaft rotates a pressurised inert gas is injected between the faces and compressed as it flows into these grooves. The gas expands again as it leaves the spiral grooves and generates a force which separates the faces to create non-contacting operation. This minimises seal face wear, reduces running and repair costs and extends seal life. Because the gap between the seal faces is kept to a minimum barrier gas usage is also reduced.