Operat ion and Maintenance Manual
QTS Series Twin Screw Positive Displacement Pump
M
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IN
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E
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Rotor Assembly
1. Make sure the mechanical seals are properly installed before assembling the rotors. If the studs
(14) were removed replace them. Insert the gasket firmly (27) on the back cover groove.
Note: To place the studs you may use the nut-and-locknut technique (see annex B).
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.
2. Mesh both rotors by hand so the front
faces match and are leveled. Turn the
drive shaft (
9
) and the rotors so the dots
correspond.
4. Slide both rotors onto the shafts
simultaneously. 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 f ollows:
24
23
26
27
6. Block the drive shaft (
9
) with the aid of a wrench to prevent rotation of the rotors.
7. Tighten rotor nuts by hand (
11
) simultaneously as far as you can; then use a six point 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.
28
Ampco Pumps Company QTS Manual M-030 Rev A 1.16
