Quincy Compressor QSB 15 HP, Instruction Manual

Page: 34 / 87

Section VI - Servicing
30
Quincy Compressor ® - QSB/T ™
Parallel (Shafts are parallel; sheaves not in line)
1) To check, use straightedge or string near sheave
centers.
2) To correct, loosen sheave and relocate on shaft
until all four points touch straightedge. Tighten
sheave in position.
NOTICE!
Never pry the belts into the sheave grooves. This
can damage the belt cords and lead to belt
turnover, short life or belt breakage.
Tension Specifications
Use belt tension tester (Quincy part # 142645) when
checking and tensioning the belts. See page 31 for
instructions on proper use of the belt tension tester.
The spring tensioning system used on 15 through 30 HP
units is designed to maintain proper belt tension.
However, it is recommended that belt tension be checked
monthly and confirmed to be within tension requirements
listed in the following table. If not, adjust per instructions
on page 32.
QSB/T 10-30 HP T
ENSIONING
D
ATA
S
PRING
H
EIGHT
(
IN
.) B
ELT
T
ENSION
(
LBS
.)
(R
EFERENCE
) P
RIMARY
F
OCUS
*
HP S
PRING
C
OLOR
M
IN
M
AX
M
IN
M
AX
15 B
LUE
5.9 6.1 6.0 7.0
20 B
LUE
5.8 6.0 6.5 7.5
25 Y
ELLOW
5.7 5.9 6.0 7.0
30 G
REEN
5.8 6.0 6.0 7.0
* Must have clearance under pin.
Belt tension should also be checked monthly on 40 and 50
HP units with the jackbolt tensioning system. Reference
the following table for the belt tension specifications on
these units. Adjust as necessary, per the instructions on
page 33.
QSB/T 40-50 HP B
ELT
T
ENSION
S
PECIFICATIONS
* ** ***
N
EW
B
ELT
A
FTER
R
UN
-
IN
R
ETENSION
B
ELT
T
ENSION
(
LBS
.) T
ENSION
(
LBS
.) (
AT OR BEFORE
) (
LBS
.)
10.5-11.5 10.0 8.5
* Applies only to new belts at time of installation.
** Run-in tension applies to belts after a 2 hour running period.
*** Belts must be retensioned at or before reaching this tension.