Mono MM

2. START-UP PROCEDURE
Pumps must be filled with liquid before starting. The
initial filling is not for priming purposes, but to
provide the necessary lubrication of the stator until
the pump primes itself. When the pump is stopped,
sufficient liquid will normally be trapped in the
rotor/stator assembly to provide lubrication upon re-
starting.
If, however, the pump has been left standing for an
appreciable time, moved to a new location, or has
been dismantled and re-assembled, it must be
refilled with liquid and given a few turns before
starting. The pump is normally somewhat stiff to
turn by hand owing to the close rotor/stator fit.
However, this stiffness disappears when the pump is
running normally against pressure.
2.1 DRY RUNNING
NEVER RUN THE PUMP IN A DRY CONDITION
EVEN FOR A FEW REVOLUTIONS OR THE
STATOR WILL BE DAMAGED IMMEDIATELY.
CONTINUAL DRY RUNNING COULD PRODUCE
SOME HARMFUL OR DAMAGING EFFECTS.
2.2 PUMP ROTATION DETAILS
PUMP RANGE BI-DIRECTIONAL COMMENT
E
Monobloc B Yes
Yes
Merlin Industrial Yes
seYLS ,S
seYFL
**W
Merlin Widethroat No
No
No
**
*oNLM MM
**oNSM
*G
*oNBS/BC
**oNrecalP
Grout Injection No **
oNP
**oN1100PC
CP0025,CP0800,CP1600 No *
*
* Clockwise when viewed from drive end.
** Anti-clockwise when viewed from drive end.
Anti-clockwise gives inlet at drive end.
DIRECTIONS OF ROTATION
BEFORE THE DIRECTION OF ROTATION IS
CHANGED, MONO PUMPS LIMITED MUST BE
CONSULTED SO THAT THE SUITABILITY OF
THE PUMP CAN BE CONFIRMED WHEN
OPERATING ON THE NEW DUTY.
2.3.1. GLAND PACKING
Where a pump is supplied fitted with gland packing
(manufactured from a non-asbestos material), the
gland will require adjustment during the initial
running in period. Newly packed glands must be
allowed to run-in with only finger tight compression
on the gland follower nuts. This should continue for
about 3 days. The gland follower should be
gradually tightened over the next week to achieve a
leakage rate as shown in the table below. Gland
followers should be adjusted at regular intervals to
maintain the recommended leakage flow rate.
Under normal working conditions a slight drip from
the gland under pressure assists in cooling and
lubricating the packing. A correctly adjusted
gland will always have small leakage of fluid.
Typical Leakage Rates from Packed Glands
Up to 50mm shaft diameter 2 drops per minute
50 … 75mm shaft diameter 3 drops per minute
75 … 100mm shaft diam
eter
4 drops per minute
100 … 125mm shaft diameter 5 drops per minute
125 … 160mm shaft diameter 6 drops per minute
A gland drip is, however, undesirable when handling
corrosive, degreasing, or abrasive materials. Under
these conditions the gland must be tightened the
minimum amount whilst the pump is running to
ensure satisfactory sealing when under pressure, or
to stop entry of air when under suction conditions.
The gland leakage of toxic, corrosive or hazardous
liquids can cause problems of compatibility with the
pumps materials of construction.
Provision of a gland drain should be considered,
especially for the leakage of hazardous products.
CARE IS REQUIRED WHEN ADJUSTING THE
GLAND WHILST PUMP IS RUNNING.
2.3.2 MECHANICAL SEALS - ALL PUMPS
When a mechanical seal is fitted to the pump it may
be necessary to provide a barrier fluid to some part
of the seal. This should be provided in line with the
seal manufacturers instructions.
2.4. GUARDS
In the interests of safety, and in accordance with the
U.K. Health and Safety at Work Act 1974, all guards
must be replaced after necessary adjustments have
been made to the pump.
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Section 1, Page 3
Issued – December 2002
Installation, Operation & Maintenance Instructions