How much is costly equipment down time worth to you?
GE Hydraulic Power Unit |
Westinghouse Hydraulic Power Unit |
|
ONE OF THE HIGHEST CATEGORIES OF FORCED OUTAGES on electrohydraulic controlled (EHC) steam turbines over the past 10 years has been the Turbine Trip and Monitoring System.* This system consists of electrical relays, mechanical valves, and the high pressure fluid system. In a majority of cases, the fluid system was either directly or indirectly responsible for the forced outage. Fluid contamination was found to be the single biggest recurring problem with the high pressure fluid system |
Reservoir Gunk |
Fluid samples before, during &
after a typical EHC flush. |
Varnish suspended in Fluid |
|
Evidence of dark green or black slime, or black particles clinging to the servo valve strainer
and/or main pump discharge filter indicate that the high pressure fluid system is contaminated. |
 EHC Fluid In most cases the contamination consists of gels and/or varnishes.
The fluid used in the EHC system (phosphate ester) is very sensitive to acid formation. The Hydraulic Power Unit (HPU) incorporates a series of filters (Fullers Earth or Selexsorb) that aid in controlling the acid build-up in the fluid. If the filters are not properly maintained, the acid levels can increase to a point where gels begin to form in the fluid. |
Dirty Inlet Suction Strainer
The gels will eventually form hard deposits on the inner surfaces of the piping, hydraulic actuators, and other mechanical components of the system. These deposits can break off during system upsets and, since they are already down stream of the pump discharge filters, they can cause serious problems with the various components of the EHC system, including servo strainer pluggage; and unnecessary wear to the pumps, servo valves and actuators due to scoring caused by the hard deposits that collect. |
The only proven way to remove these harmful deposits is through a systematic flushing process that dissolves these deposits. The fluid that is used contains amines. These amines dissolve the deposits and flush them back to the reservoir where they are easily removed.
It is critical that these amines then be neutralized and removed from the hydraulic system following the flush.
|
 The OEM flushing procedure that are included in the instruction manual applies to initial installation only. The current problems being encountered throughout the electric utility industry are long-term accumulation of contaminates. The published flushing procedure will not thoroughly flush a contaminated hydraulic system. However, the patented flushing procedures developed by Barry Sibul & Company will thoroughly remove all contaminates. |
 BARRY SIBUL And COMPANY
provides a patented flushing procedure that assures a thorough cleaning of the entire high pressure system. The flush can generally be completed in less than five (5) days from start to finish. In order to assure a thorough system flush, it is vital that the following two areas be addressed: |
In order to assure a thorough system flush,it is vital that the following two areas be addressed:
1. A detailed, engineered flushing procedure will be implemented that assures the hydraulic fluid system will be thoroughly cleaned and returned to service with assurances that the contamination will not reoccur.
2. A continuous monitoring of the fluid's condition during the flush will assure that the system is in fact being thoroughly cleaned up. The monitoring also allows the job manager to determine when "enough is enough." |
A "Turn-key" approach to
System Flushing that will
last....
The Hydraulic Fluid System Flush consists of four major elements
- On-Site Technical Direction and the supply of all special tools and supplies needed to
complete the flush
- On-Site Labor required to successfully complete the flush
- Off-Site component repair of system components completed concurrent to the flush
- New hydraulic fluid to be used during and following the flush
|
With the cooperation of its alliance partners, Barry Sibul and Company can offer a complete “turn-key” service for hydraulic fluid system flushes.
The Chemical Flush includes all of the following items provided by Barry Sibul and Company" |
1. An on-site pre-flush meeting conducted prior to the flush to go over the details of the flush
including scheduling manpower, supplies, repairs etc.
2. A customized flushing procedure based on over 38 years of experience.
3. External kidney loop filtering units that assure no particulates are added to the system when adding fluid to the reservoir during and at the conclusion of the flush.
4. A detailed Gantt chart created in Microsoft Project (or similar) that can be used to integrate the flush with the rest of the work being conducted during the outage. The manpower requirements of this Gantt chart are based on extensive flush experience and are necessary to ensure that there is no overrun on the length of the project.
5. An experienced on-site technical director to act as the job site manager to coordinate all aspects of the job, including on-site labor and off-site repair of components. The site director will be on-site
during critical stages of the flush to ensure that nothing is overlooked, will leave standing orders when not on-site, and will be available by phone or in person throughout the project.
|
6. Experienced on-site labor required to perform the flush. This includes removal of any
components that need to be sent off-site for repair, preparing the system for flushing,
flushing the system, including cleaning the HPU reservoir twice during the flush (confined
space), restoring the system following the flush including re-installation of any components
that were sent off-site for repair and starting up the system to ensure everything works properly following the flush.
7. An on-site fluid analysis person who will be taking fluid samples and analyzing the fluid throughout the flush.
8. New 275 gallon Totes that will be used to hold and filter the various EHC fluids during the flush.
|
9. A complete set of flushing valves and/or hydraulic line jumpers and ball valves to be used during the flush.
10. Special cleaning chemical (amine) used to dissolve and dislodge the varnish within the EHC system.
11. Bio-Syn EHC Fluid to be used during the Rinse phase of the flush and as the final operating fluid for the system. Bio-Syn EHC Fluid is recommended as a replacement fluid for the existing EHC Fluid. Following the flush, if the customer elects to use the same type of fluid that was in the system prior to the flush, this fluid will need to be provided by the customer. Twice the capacity of the reservoir fluid is required for the Rinse and Final fill of the reservoir.
12. All off-site repairs of components as determined by customer. This includes, Hydraulic Actuators, Spring Can Assemblies, Servo Valves, Solenoid Valves, Shut-Off Valves and Dump Valves.
|
13. Provide a complete list of customer supplied items needed for the flush including part numbers, antities and suppliers. These items include final operating system filters etc.
14. A drain pump used to drain the dirty fluid from the reservoir during the flush.
15. Kidney Loop Pump Filters used during the flush.
16. All viton seals used during the flush including seals for the flushing valves used during the flush.
17. A guarantee that following the flush the EHC fluid will meet or exceed OEM recommendations.
18. Provide a thorough written report detailing how the system was found, what was done and how the system was left.
|
| |
