Aluminum Bronze Application Spotlight: Butterfly Valve Stem Bushings

Application: Butterfly Valve Stem Bushings

Butterfly valves are used to control and isolate the flow of liquids.  The controlling method uses a disc which pivots on a stem.  These types of valves are used extensively in the oil and gas industry.  Many of these valves are located in sub sea environments which exposes the valve to multiple corrosive factors.  It is critical that the butterfly valve functions properly in these types of environments’.  For this reason most manufacturers employ a stem bushing.  The stem bushing reduces torque and isolates the stem from the body. The stem bushing prevents seizure of the stem often due to corrosion of the stem journal.

Why Aluminum Bronze?

Aluminum Bronze Alloys are incredibly resistant to corrosion.  This is due to the formation of a thin but tough adherent layer of aluminum oxide. This film is self-healing and once formed prevents further oxidation and eliminated flaking. Aluminum bronzes are also resistant to attack from a wide range of chemicals.  Also the non-sparking properties of certain aluminum bronzes are very beneficial in oil and gas applications.

The upper and lower stem bushings are commonly machined from C95400 Cast Aluminum Bronze.  Here at National Bronze Mfg. we supply both the raw material and finished stem bushings for a number of customers.  Follow the links below to learn more about various aluminum bronze alloys.

If you have any questions feel free to contact our sales department and one of our experienced sales engineers can answer your questions.

Aluminum Bronze Alloys

C95400 Aluminum Bronze Specification Sheet

Contact a Sales Engineer 

For Bi Metal Valve bushings check out Viiplus at http://viiplus.com/