Dear Sir,
I am working in project having GE FRAME 9E gas turbines and involved in commissioning,

we have received P & IDs from GE, in one of the P & ID , they mentioned two pressure transmitters, 96 BD-1, 96 CS -1, being connected between inlet planum and bell mouth, i am not clear about purpose of above two transmitters,

request to share experience,

Thanks,

 

Hi,

the mentioned P&ID is the "Performance P&ID". In case that it's mentioned in the contract, GE should supply required software and hardware to monitor Turbine performance.

software would be typically a piece of background software that is installed and running in PERF_MONT_SVR server in control room.

Hardware, performance is to calculate some important parameters that evaluate turbine & Compressor efficiency and to accomplish this inlet and oulet parameters should be measured and transmitted to MK VI then thru EGD to Performance server (Actually Mk VI doesn't make use of any of these signals just retransmit it via EGD). so as you can see in this P&ID some transmitters are installed to measure inlet air and some for outlet exhaust.

96BD "COMPRESSOR BELLMOUTH DIFFERENTIAL PRESSURE TRANSMITTER". measures the differential pressure between ambient press and inlet bellmouth press.

96CS-1 "INLET AIR TOTAL PRESSURE TRANSMITTE". measures pressure of inlet air at compressor inlt.

Thanks,
Max

 

Dear Max,

Thanks for your guidance,

it will help us as we have received only P & ID at this stage,

thanks again,

 

GTMAN,

But you need to ensure that the device names that you have mentioned are just in the control constant display or have been used in the CSP for the particular unit.

 

All the device data will be available, including the settings, in the device summary sheet. These transmitters inputs are used for the calculation of compressor pressure ration which in turn used for combustion calculations and compressor protection.

 

Hi NLN,

These transmitters are not used in any function in Mk VI, it's just for performance calculations. Compressor and combustion protection, use another transmitters.

Thanks,
Max

 

All the replies to this question are possibly correct for certain instances or applications.

The originator has not provided enough information to state why the instruments are being provided.

And just because a Frame 9E at one site has these instruments does not mean that all Frame 9Es at all sites have the same instruments for the same purpose.

These two devices are usually part of a system that either monitors air flow through the unit and/or provides information for the calculation of the Combustion Reference Temperature for DLN combustor-equipped units.

By knowing the static pressure of the inlet system and the pressure drop across the bellmouth of the turbine, a crude estimate can be made of the amount of air entering the turbine.

Units without DLN combustors usually have this equipment as part of a "performance monitoring package". Units with DLN combustors usually have this equipment as part of the Combustion Reference Temperature calculation, though it's not always provided for this purpose, either.

The originator should tell us what kind of combustor the Frame 9E he is "commissioning" has and on what P&ID the two devices appear on.

These devices should be listed in the Device Summary which should be provided with the turbine drawing package. They should also be referenced in the turbine control system. They should also be documented in the System Description provided in the Instruction Manuals provided with the unit. The Control Specification for the unit may also have some brief description of the function of the instruments, as well as any calibration/scaling information.

Everyone replying to this case should have described their unit (type of combustor; application; age of unit; etc.) and list the name of the P&ID where the instruments are shown for their unit. No one should be committing the all-too-common mistake of thinking that all Frame 9Es are alike on every site and for every application

 

Dear Sirs,

Machine at our site is PG 9171 E , NON DLN machine, and two parameters which i mentioned is appeared in P & ID called performance parameters. sorry for inconvenience, and thanks to every one for their support.