End User Perspectives on Self-Lubricating Bearings
In this roundtable discussion, fve hydro project owners and operators
provide their perspectives on the use of self-lubricating bearings for
various applications at hydropower projects around the world.
By Gregory B. Poindexter
Hydro Review spoke with fve representa- tives of hydroelectric power producers from around the world about their use
of self-lubricating bearings in their hydropower facilities.
Self-lubricating plain bearings have a lubricant contained within the bearing walls and can
run without an external lubricant. Tere are
many forms of self-lubricating bearings. Te frst, and most common, are
sintered metal bearings, which have
porous walls. Te porous walls draw
oil in via capillary action and release
the oil when pressure or heat are
applied. An example of a sintered metal
bearing in action can be seen in self-lubricating
chains, which require no additional lubrication
Another form is a solid one-piece metal
bushing with a fgure eight groove channel on
the inner diameter that is flled with graphite.
A similar bearing replaces the fgure eight
groove with holes plugged with graphite.
Tis lubricates the bearing inside and out.
Te last form is a plastic bearing, which has
the lubricant molded into the bearing. Te
lubricant is released as the bearing is run.
Tis technology is an asset in hydropower.
A study for the U.S. Army Corps of
Engineers indicates using self-lubricating
bearings eliminates the use of grease lubrica-
tion, which lessens the possibility of problems
with the environment related to water con-
tamination. 1 In addition, maintaining
lubricated bearing systems in some
applications where access is difcult
increases operational costs. 2, 3
Our sources for this article are:
Nathan Smith, PE, an engineer
for Denver Water in Denver, Colo., USA.
Denver Water serves about 1. 4 million people.
Established in 1918, the utility is a public
agency and is Colorado’s oldest and largest
water utility. Denver Water operates seven
hydroelectric power plants at its facilities,
generating more than enough energy to power
all of the water system’s 22 pump stations, four
treatment plants and other major facilities.
Jean-Louis Drommi, electromechanical
expert for the Hydro Engineering Center at
Electricite de France
(EDF). EDF is an
company and the larg-
est power producer in
France and its hydro-
accounts for 10% of
the company’s power
supplies energy and
services to about 37. 1
26. 2 million of which
are in France. EDF generated consolidated
sales of €71 billion (US$81 billion) in 2016.
Tom Freeman, senior mechanical engineer
for turbomachinery section, Hydroelectric
Design Center (HDC), U.S. Army Corps of
Engineers. Te Corps operates 75 hydroelec-
tric power plants, the most in the U.S., which
have a total installed capacity of 20,474 MW.
Annually, they produce nearly 100 billion
k Wh, almost a third of U.S. total hydropower
output. HDC is located in Portland, Ore., and
performs planning, engineering and design,
maintains expertise, and develops standards
for the Corps’ hydroelectric power facilities
and large pumping plants.
Tyler Barrett, hydro maintenance super-
visor for Duke Energy. Duke Energy owns
and operates 31 hydropower plants in North
America and is one of the largest electric power
holding companies in the U. S., supplying and
delivering electricity to about 7. 4 million U.S.
customers. Duke Energy has about 52,700
MW of electric generating capacity in the
Carolinas, the Midwest and Florida and
operates 31 hydroelectric power plants.
Brad Tooktoshina, generation maintenance supervisor for Newfoundland Power.
Newfoundland Power operates 23 hydropower plants and is located in St. John’s,
Newfoundland and Labrador, Canada. Te
company operates an integrated generation,
transmission and distribution system throughout the island portion of Newfoundland and
Labrador. Newfoundland Power purchases
about 93% of the electricity it sells from
the Crown corporation, Newfoundland and
Labrador Hydro, and generates the balance
its own smaller hydroelectric stations located
across the island. Example of self-lubricating bearing types for hydro. (Photo/Kamatics)