DRIVES , MOTORS & GEARS KEEPING POWER ONLINE
SULZER
Extending small steam turbine performance and reliability to minimize costs
Beyond the large units driving generators , small steam turbines are commonly used in parallel with electric motors to power important assets such as pumps . Keeping these smaller turbines properly maintained is essential for continued performance and reliability . Sulzer has a network of specialized facilities that are equipped to service these turbines as well as the rotating equipment that they drive .
Small steam turbines , typically producing less than 1 ’ 500 hp ( 1 ’ 100 kW ), are often used in industrial environments , such as chemical , oil refinery , paper mills , power plants and many food industries . These may be a primary driver or a standby unit for the back-up of a motor-driven unit .
Typical service intervals for small steams turbines are six to seven years , with biennial planned maintenance . Steam conditions play a major role in increasing unit availability and downtime for repairs . Where wet steam conditions are found , various coatings can be applied to reduce wear . A field site visit to review case , steam valve and carbon gland leak-off provisions is key to ensuring the drain or leak-off is adequate to minimize the wear on turbine parts .
It is important to understand the key points of a small steam turbine that need to be properly maintained for continued safe and efficient operation . At the top of this list is the overspeed trip mechanism . The trip safety device is designed to operate in the event of a governor failure and prevent the turbine increasing in speed to the point of destruction . It is essential that any turbine overhaul includes a check for the correct operation of the overspeed mechanism .
SIMPLIFYING MAINTENANCE
Steam turbine health relies on the bearings being properly maintained . These could be a roller bearing or a white metal , Babbitt , bearing , both of which need to be monitored for wear and to highlight any signs of failure . These may include water contamination of the oil system , misalignment or incorrect oil levels . Frequent monitoring of oil quality , oil temperatures and performing scheduled vibration measurements for analysis is key for turbine reliability .
Sulzer has a long-established expertise in steam turbine design , operation and repair . Decades of experience of working with assets from a wide variety of manufacturers means that customers can benefit from a rich bank of knowledge and understanding .
Coupled with a network of service centers that are equipped with all the necessary machine tools , and the ability to maintain all types of rotating equipment , Sulzer offers a local one-stop-shop for a wide variety of machinery repairs . This includes small steam turbines , which can be fully tested using in-house test stands and lube oil systems that have been installed specifically for this service .
42 PECM Issue 47