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17 - ENGINEERING DATA
17.1 -
INFLUENCE OF SERVICE LIQUID TEMPERATURE, SPECIFIC GRAVITY
AND VISCOSITY ON PUMP PERFORMANCE
The per formance of liquid ring vacuum pumps is based on the use of water at 15
°C as ser vice liquid. With water at different temperatures the pump capacity and
the maximum attainable vacuum level will var y as a function of the type of pump,
as illustrated by the cur ve sets of fig. 29 and 30.
EXAMPLE: Pressure = 45 Torr - Water temperature = 24°C - Pump series TRH -
Capacity (15°C water) = 310 ACFM From cur ves of fig. 30 we find the correcting
factor of 0.80, therefore the actual capacity for the pump at the given conditions
will be:
310 x 0.80 = 248 ACFM. The maximum suction pressure before incur-
ring cavitation will be approximately 35 Torr.
Regarding the per formance variation due to changes of specific gravity and vis-
cosity, it can be assumed a propor tional variation in power consumption however;
the changes in capacity at different pressures must be analyzed case by case.
Please refer the conditions to TRAVAINI PUMPS USA when these corrections are
needed.
• if required, remove the motor anchor bolts on the baseplate, for base mounted
assembly, or the bolts on the adapter flange in the case of monoblock design
• remove the pump anchor bolts on the baseplate
• remove the pump from the installation. Avoid damaging other system compo-
nents.
After pump repairs, re-install following the steps from “Assembly and Alignment”
procedures and after (see the applicable chapters).
16 - SPARE PARTS
When ordering the pump it is good practice to also order the necessar y spare
par ts, especially when there are no stand-by pumps in the installation. This will
minimize unnecessar y down times in the event of pump failure or routine mainte-
nance.
It is therefore, recommended to stock the following spare par ts for each pump
size:
(1)
Impeller set
(1)
Complete shaft assembly
(1)
Bearing set
(1)
Mechanical seal set (or packing set)
(1)
Gasket sets
(1)
Radial seal ring set
(1)
Bearing spacer set
(1)
Coupling rubber inser t set
For better par ts management, the VDMA 24296 standards suggest to stock the
number of par ts as a function of the number of pumps being used in the plant.
On the pump nameplate are printed pump model, year of manufacture and pump
serial number. When ordering spare par ts always provide this information. Pump
type, par ts item number (VDMA) and description as per the pump sectional draw-
ing and par ts list is useful information that helps to supply correct spare par ts for
your pump. We recommend the use of original spares: in case this is not respect-
ed, TRAVAINI PUMPS USA declines any responsibility for eventual damages and
not correct running caused by not original spare par ts.
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