29
Operation and Maintenance Manual
QTS Series Twin Screw Positive Displacement Pump
QTS-M04
M
A
INTE
N
A
N
C
E
Rotor Assembly
1. Make sure the mechanical seals are properly installed before assembling the rotors. If the studs
(
14
) were removed place them back. Insert firmly the gasket (
27
) on the back cover groove.
Note:
To place the studs you may use the nut-and-locknut technique (see annex B).
2. Shafts and rotors are marked on the front face with dots to indicate the position of the rotor
relative to the spline on the shaft; the rotors are also marked to identify which is the right rotor (
3
)
and the left rotor (
2
), it is important to match each rotor with its respective shaft for the right
operation of the pump.
3. Take both rotors together with your
hands and mesh them so the front faces
match are leveled. Turn the drive shaft (
9
)
and the rotors so the dots correspond.
4. Slide the rotors together onto the shafts.
Some alignment might be needed. By
effect of the mechanical seals the rotors
have not yet reached their final position; it
is necessary to tighten the nuts.
5. Place the set screws (
24
), the spring
washers (
23
) and the O-rings (
26
) on the
rotor nuts (
11
). Assembly the rotor nuts and tighten the rotor nuts as follows:
27
24
23
26
6. Block the drive shaft (
9
) with the aid of a wrench to prevent rotation of the rotors.
7. Tighten by hand the rotor nuts (
11
) simultaneously as far as you can; then use a six points
female socket to tighten the nuts. Gradually tighten both nuts simultaneously to avoid contact
between them.
8. When the rotors reach their end position with the mechanical seals and shafts, tighten the nuts
with the torque values according to the pump model. The front faces of the rotors should be aligned.
