Varisco S.p.A.
Z.I. Nord - Terza Strada, 9 - 35129 PADOVA – ITALY
Tel.+39.049.8294111 Email: [email protected]
Fax+39.049.8076762 Web: www.variscospa.com
11
Therefore, during assembly, it is necessary to be careful not to move excessively the axis of the
hollow shaft. Oil the male shaft of the motor/converter, place it so that its key is in line with the
corrispondant bore.
Engage the propeller shaft until the two flanges (the motor’s and the pump’s) were connect. Then
turn the motor/converter until the bolts holes of the flanges coincide. Let the pump shaft hit the
motor shaft and tighten the grub screw (line it up with the cavity set it up on the gearmotor shaft).
6.1.2.2 BEARING HOUSING VERSION
(WITH ELASTIC JOINT)
Insert the half-joints (or pulleys, if belt drive is employed) at the ends of the shaft
without using a
hammer
or other tools which may damage parts inside the support. For assembly, use the threaded
hole on the end of the shaft.
The accurate alignment of motor and the male shaft of the pump is an essential condition for a
proper operation.
If the pump is delivered completed, the alignment has already been carried out at the factory.
Nonetheless, it is possible that during the positioning on the floor a misalignment may occur,
therefore it is necessary to remove the joint cover and check its alignment by means of a ruler
before startup. If the foundation is not properly leveled, the base may buckle. The tolerances usually
allowed in joints used by the company are:
•
Allowed radial variation = 1%
•
Allowed angular variation = 1°
6.1.3 DIRECTION OF ROTATION
The direction of pump rotation is shown on the label pump and described on the order
confirmation.
The direction of pump rotation sets the direction of the flow through the progressing cavity pump.
Any different setup must be agreed with the supplier and approved by the same.
By changing the direction of pump rotation, the product flow reverses.
If the pump turns clockwise, seen from the motor side, it intakes from the orifice at the end and
delivers from the middle one; if the pump turns counterclockwise it intakes from the middle orifice
and delivers from the one at the end (see below).
Usually, the pump can work in both directions, be it mounted with packing or with a mechanical
seal (unless it uses omokinetic joints which allow just one direction).
It is advisable, though, to use the pump turning counterclockwise to prevent that the packing rings
(or the mechanical seal) or other parts were subject to high pressure that could be difficult to
monitor.
The pumps with a mechanical seal, though reversing, shall always turn in the direction indicated on
the pump label.
This direction of rotation shall be preset upon the order while the seal assembled shall be preset at
the factory.
