February 21, 2008

Pump Materials Improvements Result in Lower Maintenance and Operating Cost - Hot Topic Hour Thursday Afternoon

The first speaker was Folke Friesen of Evonik. He made recommendations for pump selection based on the decades of experience of his company (formerly Steag) in operating FGD pumps. He showed the wear problems associated with elastomeric linings. He also showed the wear problems experienced with duplex steel all metal pumps. In contrast the experience with ceramic pumps has been extremely good.  Pump life has been greatly extended and maintenance reduced.

Mike Agosti of Lawrence Pumps explained that his company imports the ceramic pumps from Düchting and then provides final assembly and shipment within the U.S. The latest model provides up to 75,000 gpm. By utilizing various particle sizes of silicon carbide it is possible to maximize the ratio of carbide to binder. This greatly improves wear resistance. Mike also showed performance graphs illustrating the loss in flow as the pump wears. A 33 percent loss in flow means that more pumps have to be in operation and therefore the energy consumption will be considerably higher.

Jim Burke of Weir provided the good news that manufacturing capacity is up and deliveries are now less than one year. Weir has continually improved the materials utilized in its pumps. A steady progression in lining improvements has led to a long life. The impeller material is a special high alloy steel which combines both wear and corrosion resistance. The impeller design provides high efficiency.

Also discussed were the designs and advantages of mechanical seals. The Weir GSL pumps are all designed to accept the cartridge seals from John Crane, Flow Serve and Burgmann.

Water flushing will prolong seal life but is not always an option. Weir has a valve (patent pending) which opens when pressurized and closes when pressure is removed. Water can be controlled with a valve connected to the thermocouple for automatic operation. It is important to flush pumps for as long as 20 minutes after a pump is taken off line. Many operators do not follow this practice and thereby shorten pump life.

The individual power points can be accessed at:

Continuing Decision Process For: Pumps

Folke Friesen – Evonik
http://www.mcilvainecompany.com/FGD_Decision_Tree/subscriber/Tree/DescriptionTextLinks/Evonik Energy Servcies pump experience.pdf

Mike Agosti – Lawrence Pumps

Continuing Decision Process For: Products

Hot Topic Hour February 21, 2008.

http://www.mcilvainecompany.com/FGD_Decision_Tree/subscriber/Tree/DescriptionTextLinks/FGD Pumps - Duchting Pumps.htm
 

Jim Burke - Weir

Continuing Decision Process For: Products

Hot Topic Hour February 21, 2008

http://www.mcilvainecompany.com/FGD_Decision_Tree/subscriber/Tree/DescriptionTextLinks/Hot Topic Hour Weir Pump Presentation.htm