INTRODUCTION Installation of gas charged accumulator with flexible rubber diaphragm stabilize the oil pressure during the rapid and improvvise change events to avoid shut down of running machine without real situation of that necessity. The standard kit has been designed to be easily installed by proper bracket system and supports in proximity of any N.P. steam turbine skid. TECHNICAL DESCRIPTION The gas precharged accumulator is phisically a vertical under pressure tank with proper selected volume choosen taking account of operating conditions of running machine and involved oil piping volumes and flow. A gas precharged flexible rubber diaphragm is installed inside the oil accumulator cilinder to be filled by inert gas (usually nitrogen) by a proper filling equipment supplied in the kit. This assembling assure no contact between oil and inert charge gas. The inert gas charge is set at fixed pressure to avoid necessity of regulating valve that may became itself source of hunting and transmit to regulated oil pressure undesidered rapid fluctuations. Oil accumulator is choosen to supply needed oil flow to the load during the pressure transient time stabilizing the pressure on the main manifold. Casing tickness is sized in agreement with ASME VIII Point 1 or according special requirements of final installation country on customer request.
BENEFITS Oil accumulator installation is able to: a) eliminate shut down of steam turbines due to control oil pressure instantaneous drop and consequent closing of oil actuated valve on live steam inlet b) avoid shut down of on duty Steam turbines due to instantaneous lube oil pressure drops c) improve stability of regulated oil pressure with less vibrations and pulsation stress transmitted to the equipments and instrumentation on oil piping d) reduce st-by oil pump start-up avoiding abnormal stress and opening of pump discharge safety valves due to overpressure e) limit possible breaking of gasket or squashing of filter cartdridges due to instantaneous overpressure expecially during changeover of pumps. SCOPE OF SUPPLY Supplied items are: • Proper size and volume selection calculus • Cilinder design data sheet according ASME VIII • Installation typical sketch Installation kit on standard control oil manifold of any N.P. steam turbines comprensive of: • oil accumulator with brackets • isolating main valve • interconnecting piping to control manifold
APPLICATIONS Gas precharged Oil accumulator can be installed: 1) on control oil main manifold of steam turbines to stabilize oil pressure to speed governor or steam extraction hydraulic actuators (standard kit); 2) on any lube oil system manifolds where oil pressure drop are possible due to stop of main and restart of stby pumps.
GE Power Systems Oil & Gas Nuovo Pignone
CM&Us
Us
STEAM STEAM TURBINES TURBINES
CONTROL OIL PULSATION DAMPNER
CM&
TU/VA07-9/2002
CONTROL OIL PULSATION DAMPNER • • • • •
orificed no return valve support to be welded at turbine baseplate gaskets flanges nuts and bolts tee and welding reduction to add needed piping connection on existing manifold • drain pipe with orifice • complete and removable after filling gas pressure verification kit suitcase Options Design for special installations not covered by standard preengineered kit. Design according customer requirements instead of ASME VIII Pt 1. STEAM TURBINE BASEPLATE
STEAM TURBINE CONTROL OIL MANIFOLD
REMOVABLE GAS PRESSURE VERIFICATION ASSY
PI
OIL ACCUMULATOR
TYPICAL INSTALLATION ON LUBE OIL HEADER
TYPICAL INSTALLATION ON STEAM TURBINE CONTROL OIL MANIFOLD
TO LUBE OIL RESERVOIR LUBE OIL MANIFOLD
CONTROL OIL
OIL FROM LUBE OIL CONSOLE TO OIL DISCHARGE MANIFOLD Nuovo Pignone S.p.A. via F. Matteucci, 2 - 50127 Florence (Italy) Tel. +39-055-423-211- Fax +39-055-423-2800 E-mail:
[email protected] www.gepower.com/geoilandgas
COMK/MARK 717/II- Studio Tre Fasi - 9-2002 ©2002 Nuovo Pignone S.p.A. all rights reserved
OIL ACCUMULATOR
DISCHARGE OIL MANIFOLD