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BEARINGS, BELTS & CHIAINS
Converting to
synchronous
belts cuts
HVAC costs
by $34,000
US-BASED Reichhold Corporation is a
global supplier to the composites and
coatings industries, with 18 manufacturing
facilities in 11 countries. During the hot
summer months, the energy to run beltdriven
HVAC systems at its site in Durham,
North Carolina, was costing it about
$80,000 a month.
The site’s maintenance technician called
in a representative from the belt-maker
Gates to survey the plant for potential
energy savings on its V-belt driven systems,
which included 21 HVAC systems powered
by 30hp (22.4kW) motors, 44 fume hood
exhaust fans powered by 5–10hp (3.7–
7.4kW) motors, and four cooling tower
fans powered by 50hp (37kW) motors.
The HVAC drives were being driven by
four-strand V-belts which needed frequent
retensioning, and had to be changed every
three months. Gates replaced them with
Before and after: a cooling tower fan with a five-strand V-belt drive (left)
and the same fan with a synchronous belt drive (right)
14mm Poly Chain GT Carbon synchronous
belt drives, and monitored them.
The current being drawn per belt fell
from 12.5A to 10.4A, and the annual KWh
usage dropped to 10,103–10,557kWh,
representing annual energy savings of
$505–527. Converting all 21 belts
represents an energy cost saving of at least
$10,608. In addition, the synchronous belt
drives should run for years without needing
to be retensioned or replaced, avoiding
extra downtime and maintenance costs.
The Reichhold facility also includes two
1,200-tonne chillers and cooling towers.
Each cooling tower had two fan drives
fitted with V-belts. When one drive was
converted to a 14mm synchronous belt
drive, the savings were substantial. The
estimated annual saving of converting all
four fans is $12,595, including reduced
downtime and maintenance costs.
Although the 44 fume hood exhaust fans
on the roof of the Reichhold facility are
covered, they are subject to extreme
variations in temperature. Previously they
were driven by two-strand V-belts which
had to be replaced every three months and
were each costing $250 a year to maintain.
By changing to 8mm synchronous belt
drives, energy consumption fell by 12.9%.
Converting all 44 drives is cutting
maintenance costs by $11,000/year, in
addition to the energy cost savings.
In total, the maintenance and energy
cost savings achieved by converting the
various V-belt drives at Reichhold site to
synchronous belt drives is amounting to
more than $34,000 a year.
34 November/December 2010 www.drives.co.uk