Calpeda MXV Original Operating Instructions Download Page 50

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9.1. Replacing the mechanical seal

Remove the mechanical seal (36.00), the rotating part from the
shaft (64.00), making sure the shaft is not scratched, and then
the fixed part from the upper cover (34.02).

Make sure the spring of the

new mechanical seal

is set with the

direction of the winding suitable for the direction of rotation of the
shaft: i.e. counter-clockwise when seen from the stationary ring.

Make sure that all parts with which the mechanical seal comes
into contact are perfectly clean and free from any burr or cutting
edges.

The seal rings in EPDM

(Ethylene-Propylene)

must never

come into contact with oil or grease

. To facilitate the mounting

of the mechanical seal, lubricate the shaft, the seating of the
stationary part and the seal rings with clean water or any other
lubricant compatible with the material in which the seal rings are
made. Push the rotating part as far as the shoulder ring (36.52)
on the shaft (64.00), without compressing the spring. Check the
length before and after insertion and raise the rotating ring as
far as the initial length (L1 in

fig.5

In this way, correct compression of the spring will be ensured
when the fixed part is mounted and after the shaft is locked in
the coupling (L2 in

fig.6b

Use every precaution so as not to damage the seal surfaces
with blows or angular impact.

9.2. Replacing the ball bearing

If the ball bearing (66.00) has to be replaced, use a 2Z C3-type,
of the size marked on the ball bearing to be replaced and
containing grease lubricant suitable for the operating temperature.

The size of the bearing depends on the size of the motor:

motor size

ball bearing

100-112

6208, 2Z, C3

132

6310, 2Z, C3

160-180

6313, 2Z, C3

9.3. First-stage bearing and intermediate bearing

The

MXV 50-16

65-32

and

80-48

pumps have a bearing sleeve

(64.10) on the shaft (64.00) and a bearing in the stage casing
(25.03) behind the first impeller (according to the order of suction).
Starting with the

MXV 50-1611, MXV 65-3208

and

MXV 80-4806

units, there is also an intermediate bearing (see

section 13.1.

If they are to be dismantled, first number the position of each
stage casing and the single spacer sleeves (see lengths and
positions of sleeves in

section 13.2.

) so as to be able to re-

mount the components correctly.

10. Remounting

To remount the components follow the dismantling procedure in
inverse order (see

section 9.

Check the state of the o-rings (14.20) and replace them of they
are damaged.
Make sure that the o-rings (14.20) are correctly inserted on their
seats on the pump casing (14.00) and upper cover (34.02). Lu-
bricate the seal rings with clean water or any other compatible
lubricant.

10.1. Tightening torque

impeller

nuts

screws (61.07) screws (64.25) screws (70.18)

nuts (28.04)

(61.04)

lantern -

in the

with nuts

on tie-bolts upp. cov.

coupling

(70.19)

35 Nm

50 Nm

60 Nm

50 Nm

40 Nm

When tightening the nuts (28.04),

be careful not to scratch

the shaft

with the second wrench used on the opposite side.

ATTENTION: the nuts (61.04) on the tie-bolts (61.02), the screws
(61.07) on the upper cover and the screws (70.18) with the nuts (70.19)
on the lantern bracket must be uniformly tightened with alternated
crossover tightening procedure in diametrically opposite positions.

10.2. Axial position of the pump rotor

In the vertical position and from the resting position (

fig.6a

raise the rotor, levering on a pin inserted in the hole in the shaft,
until the pin can be rested under the coupling (64.22).
In this position (

fig. 6b

), by tightening the screws (64.25) uni-

formly, the shaft (64.00) is locked tight in the coupling.

Remove the pin.

Mount the motor as indicated in

section 4

11. Horizontal installation
11.1 Connection of support feet

For the mounting of the support feet all tour nuts (61.04) on the
tie-bolts (61.02) must be removed (see cross-section drawing in

section 13.

ATTENTiON: do not loosen only the two nuts

on the side of

the upper cover to which the support foot is to be attached.

To remove the 4 nuts (61.04) the lantern bracket (32.00)
must be removed.

With the pump in the vertical position, carry

out dismantling sequences 1 - 6 in

section 9

Remove the washers (61.03) and attach the support foot
(61.30) on the side of the upper cover (34.02) in the appropriate
position depending on the directional arrangement of the pump
casing (14.00) suitable for the system: suction on the left and
delivery on the right, or vice-versa (

fig.7

)

Do not insert the two washers (61.03) on the support foot when
the tie-bolts (61.02) do not protrude from the nuts (61.04).

The 4 nuts must be uniformly tightened with alternated
crossover tightening procedure in diametrically opposite
positions

. Tightening torque as per

section 10.1

Mount the lantern bracket (32.00) with the coupling (64.22) and
position the pump shaft as indicated in

section 10.2

Mount the motor as indicated in

section 4

, and orientate the

terminal board with respect to the support foot (61.30) in the
position most suitable for the system.
After setting the pump in the horizontal position, fix the second
support (61.30) to the base (61.00), with the screws (61.30),
washers (61.34) and nuts (61.36), and check for accurate
levelling of the installation with respect to the first foot.

12. Spare parts

When ordering spare parts please quote their designation, position
number in the cross section drawing (

section 13.

) and rated

data from the pump name plate (type, date and serial number).

Any

pumps that require inspection/repair

must be

drained and carefully cleaned inside and outside
before dispatch/submission.

Changes reserved.

64.00

36.00
Parte