zdas04
Mechanical
- Jun 25, 2002
- 10,274
Like most Oil & Gas Facilities Engineers I know, I've always left frame and cylinder selection to the packagers (within reason). I'm currently working of a feasibility study and didn't want to ask too much of packagers on a project that may never turn into a sale so I did the preliminary sizing myself.
The application was 9.8 MMCF/d of 98% CO2 2% CH4 going from 93 psia to 861 psia (elevation is 7,300 ft, suction temp 90F) which works out to about 1,380 hp.
It looked to me like the JGK/4 was a good fit for the task (Ariel Performance calculated 312 hp/throw in the first stage, 504 hp in the second, and 242 hp in the third running at 900 rpm).
I asked a packager for lead time on a JGK/4 matched with a CAT 3608 GLD and he came back saying that the application would be a lot better with a JGC/4 (without any clear definition of "better"). To match the machine to the flow, I either needed to reduce the first stage cylinders from 12.5 to 10.5 (which increased the hp requirement to 1586) or slow the driver to 725 rpm.
The JGK is 5.5 inch stroke rated at 635 hp/throw (max for a 4 throw is 2,540 hp). The JGC is 6.5 inch stroke rated at 1,035 hp/throw (max for 4 throw is 4,140 hp).
Do any of you have a feeling of why the packager would prefer the JGC/4 in this application (especially when they have packaged more JGK/4 frames than anyone else, yeah, it is that packager)?
David
The application was 9.8 MMCF/d of 98% CO2 2% CH4 going from 93 psia to 861 psia (elevation is 7,300 ft, suction temp 90F) which works out to about 1,380 hp.
It looked to me like the JGK/4 was a good fit for the task (Ariel Performance calculated 312 hp/throw in the first stage, 504 hp in the second, and 242 hp in the third running at 900 rpm).
I asked a packager for lead time on a JGK/4 matched with a CAT 3608 GLD and he came back saying that the application would be a lot better with a JGC/4 (without any clear definition of "better"). To match the machine to the flow, I either needed to reduce the first stage cylinders from 12.5 to 10.5 (which increased the hp requirement to 1586) or slow the driver to 725 rpm.
The JGK is 5.5 inch stroke rated at 635 hp/throw (max for a 4 throw is 2,540 hp). The JGC is 6.5 inch stroke rated at 1,035 hp/throw (max for 4 throw is 4,140 hp).
Do any of you have a feeling of why the packager would prefer the JGC/4 in this application (especially when they have packaged more JGK/4 frames than anyone else, yeah, it is that packager)?
David
