UB USER INSTRUCTIONS ENGLISH 71569247
®
5.9.4Net positive suction head (NPSHA)
NPSH available (NPSHA) is a measure of the head available in the pumped liquid, above its vapour pressure, at the pump suction branch.
NPSH required (NPSHR) is a measure of the head required in the pumped liquid, above its vapour pressure, to prevent the pump from cavitating. It is important that NPSHA > NPSHR. The margin between NPSHA > NPSHR should be as large as possible.
If any change in NPSHA is proposed, ensure these margins are not significantly eroded. Refer to the pump performance curve to determine exact requirements particularly if flow has changed. If in doubt please consult your nearest Flowserve office for advice and details of the minimum allowable margin for your application.
5.9.5 Pumped flow
Flow must not fall outside the minimum and maximum continuous safe flow shown on the pump performance curve and or data sheet.
6MAINTENANCE 6.1 General
It is the plant operator's responsibility to ensure that all maintenance, inspection and assembly work is carried out by authorized and qualified personnel who have adequately familiarized themselves with the subject matter by studying this manual in detail. (See also section 1.6.2.)
Any work on the machine must be performed when it is at a standstill. It is imperative that the procedure for shutting down the machine is followed, as described in section 5.8.
On completion of work all guards and safety devices must be
Before restarting the machine, the relevant instructions listed in section 5, Commissioning, start up, operation and shut down must be observed.
Oil and grease leaks may make the ground slippery. Machine maintenance must always begin and finish by cleaning the ground and the exterior of the machine.
If platforms, stairs and guard rails are required for maintenance, they must be placed for easy access to areas where maintenance and inspection are to be carried out.
The positioning of these accessories must not limit access or hinder the lifting of the part to be serviced.
When air or compressed inert gas is used in the maintenance process, the operator and anyone in the vicinity must be careful and have the appropriate protection.
Do not spray air or compressed inert gas on skin.
Do not direct an air or gas jet towards other people.
Never use air or compressed inert gas to clean clothes.
Before working on the pump, take measures to prevent an uncontrolled start. Put a warning board on the starting device with the words:
"Machine under repair: do not start".
With electric drive equipment, lock the main switch open and withdraw any fuses. Put a warning board on the fuse box or main switch with the words:
"Machine under repair: do not connect".
Never clean equipment with inflammable solvents or carbon tetrachloride. Protect yourself against toxic fumes when using cleaning agents.
6.2 Maintenance schedule
It is recommended that a maintenance plan and schedule is adopted, in line with these User Instructions. It should include the following:
a)Any auxiliary systems installed must be monitored, if necessary, to ensure they function correctly.
b)Gland packings must be adjusted correctly to give visible leakage and concentric alignment of the gland follower to prevent excessive temperature of the packing or follower.
c)Check for any leaks from gaskets and seals. The correct functioning of the shaft seal must be checked regularly.
d)Check bearing lubricant level, and if the hours run show a lubricant change is required.
e)Check that the duty condition is in the safe operating range for the pump.
f)Check vibration, noise level and surface temperature at the bearings to confirm satisfactory operation.
g)Check dirt and dust is removed from areas around close clearances, bearing housings and motors.
h)Check coupling alignment and
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