CENTRIFUGAL PUMP - OVERHAULING PROCEDURE FOE MULTISTAGE CENTRIFUGAL PUMP

OVERHAULING PROCEDURE FOE MULTISTAGE CENTRIFUGAL PUMP 

BASIC PROCEDURE:

• First we have take the permit, Prepared the tools and as per permit requirement.
• Inspect the mechanical and Electrical isolation.
• Inspect the blinding location as per P&ID (PERMIT IDENTIFICATION)
• Inspect pressure gauge zero and opening drain valve

OVERHAULING PROCEDURE:

• Remove Coupling hub with use of the puller
• Remove bearing housing top covers of both inboard and outboard sides.
• take out journal and thrust bearing in the outboard side and journal bearing in the inboard side
• Dismantle the bottom bearing split housing of outboard side
• Remove thrust collar from shaft
• Remove all seal parts from head on both sides.
• Cover the shaft on the bearing seated surface finished area on the tape
• Loosen and remove the head bolts connected with barrel of pump to let the rotor free to remove after taking out the head from position by the jack blots provided on the head. care should be taken about the gaskets. inner and outer and the removal of discharge diffuser case.
• fix the fixture to guide the rotor assembly.
• pullout the rotor assembly including inlet guide vane case, intermediate stage housing with care
• check the keyway of barrel.
• transfer the rotor assembly to workshop for the next step of action.
• Remove tie rods, which connects of all cases and key on the cases.
• Remove balancing piston by loosing locknut.
• Dismantle diffuser, stage bush, impeller, impeller keys, inlet guide vanes with diffuser of all stages respectively.
• Now dismantle of all parts completed.
• proper tracing of parts need to any vision able damage like crack, score, break, etc., while dismantling.
• The following measurement should be measured and recorded for analyzing the performance like wear ring clearances, stage bush clearances of all stages, bearing diametric clearance, thrust allowance, shaft trueness, seal setting compression, etc., while after dismantling.
• Care should be taken about all allowable factors with in design limits.
• Changing new parts is better than re conditioning.
• Assembling is reversal procedure for dismantling before seen. proper tightening torque should be followed is carry over.
• Before coupled with drive alignment should be checked and corrected to retain within limit