With no standard solution available, AESSEAL® initiated a development program in order to design a practical solution for the customer. The challenge for AESSEAL® was to:
- Replace the existing carbon box seal
- Utilise standard seal faces (ensuring modularity) with gas lift technology
- Incorporate high temperature polymers
- Utilise a graphite wedge shaft seal
- Incorporate into a compact cartridge design that installs to the existing envelope and pcd
- Cope with; high rotational speeds, as well as slow roll and wet steam
Working with the customer on the design and subsequent test program, AESSEAL® developed a solution for the application. After completion the customer witnessed in-house testing, the seal was installed to a known “Bad Actor”, on site for a 3 month trial. After 2 months successful operation the customer waved the rest of the trial and placed orders to install identical seals on two more steam turbines with a view to convert all the steam turbines on site.
Steam loss is a major problem on a Refinery as it incurs considerable costs. A significant benefit of the new seal is that it has eliminated steam leaks previously present; this represents a significant saving for the customer because:
- The Refinery has approximately 150 Steam Turbines meaning the cost of steam has a major impact on the profitability of the business
- There is a Health and Safety Issue as the steam produces a veil which affects vision causing a potential problem when working on or around the turbine
- There is an environmental impact caused by the burning of extra fuels Steam leakage also contaminates the bearing’s lubrication causing them to fail prematurely.
Cost of steam loss from a Single Turbine:
Average steam loss rate from turbine: 200 lb/hr or 0.0907 T/hr
Turbine runs 24/7, 365 days a year: 8,760 hrs total
0.0907 x 8760 = 794.53 Tons of steam lost per year
Cost of steam @ £17.84 /T
794.53 x £17.84 = £14,174.45
Total Cost of lost steam / Steam Turbine/Year is approximately £15,000.00
Potential Saving to the Refinery with all the 150 Steam Turbines fitted with Steam Turbine Mechanical Seals is £15,000 x 150 = £2,250,000 per Year
Without Steam Turbine Seal 
With Steam Turbine Seal
Benefits of Steam Turbine Mechanical Seal Technology on this Refinery:
- Increased turbine reliability
- Reduced turbine maintenance costs
- Reduced bearing contamination
- Extends life as non-contacting technology
- Elimination of Shaft Wear – generated by the Carbon seal
- Greatly reduces steam loss and increasing efficiency
“These Steam Turbine seals are so good you should be looking at rolling them out to refineries worldwide”
Refinery Workshop Manager
Welcome to AESSEAL® : A specialist in the design and manufacture of mechanical seals and support systems. Our Mechanical Seals are used in a wide range of pumps and rotating equipment worldwide to prevent liquids and gases escaping into the environment. We manufacture mechanical seal types to suit all industries and our investment in modular design ...
