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Lolz MBAs can't think, they just run spreadsheets!Originally posted by davbrucasI want to like Slow99 since people I know say he's a good guy, but just about everything he posts is condescending and passive aggressive.
Most people I talk to have nothing but good things to say about you, but you sure come across as a condescending prick. Do you have an inferiority complex you've attempted to overcome through overachievement? Or were you fondled as a child?
You and slow99 should date. You both have passive aggressiveness down pat.
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Here is hoping for a cold winter.
I don't think you can take any forecast seriously until the election. Halliburton told me a month ago they were going to build the most equipment ever next year and two weeks later they said they may have overestimated.
Lead times on most equipment is coming down except for things like coiled tubing, cementers and nitrogen rigs. Anyone can build a frac but only certain companies have the engineering capability to do these, especially with Tier 4 engines. As Matt said natural gas to run equipment will probably be the next big thing.
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Originally posted by Sean88gt View PostAs I said elsewhere - The MBA has largely replaced intelligent leadership. What a lot of "leaders" simply don't understand is that a spreadsheet isn't the end all be all of business success, sometimes it takes thought.Originally posted by BradMBut, just like condoms and women's rights, I don't believe in them.Originally posted by LeahIn other news: Brent's meat melts in your mouth.
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Originally posted by 03mustangdude View Postdoes any company even make equipment to run natural gas on rigs
Three 50 liter diesel SCR sets on a drill rig is about comparable to six 50 liter spark ignited natural gas SCR sets on a site.
Originally posted by Trip McNeely View PostSeneca will have 100% LNG Rigs here soon.
With a dual fuel solution you can still run diesel ignition and diesel cylinder pressures which means you can have diesel style torque curves with your equipment.
*** engine tech warning***
A diesel engine runs purely on compression. No spark. Whatever fuel is in the cylinder... doesn't matter. At some point there's enough compression to heat the fuel enough that it combusts.
There are hybrid systems that use a specialized injector that run both NG and diesel at once. These systems, pioneered by Westport Innovations Inc in Vancouver, use two fuels through one injector. There is a 5% diesel injection into the cylinder to preheat the air (to take the place of a spark plug) then there is a 95% NG injection that autoignites (with the same cylinder pressure as a diesel application) that does work on the piston. This allows a "natural gas" engine to achieve diesel like torque curves while running on primarily NG fuel, but that's not what we're talking about here.
Now back to diesel engines...
If you take a diesel engine in the field and expose it to a cloud of fuelgas then the engine will ingest the gas. If the engine "throttle" position is maintained then this extra fuel gas will cause the engine to speed up. The engine fuel pump can cut supply but if the atmospheric gas is of sufficient quantity then it can keep the engine running or even cause a runaway.
Remember that a diesel engine does not have an intake air throttle blade. It controls speed purely on fuel input. If there's an uncontrolled fuel input (ambient cloud) then there is potential for uncontrolled speed. (The only way to stop a runaway due to atmospheric gas is with an air shutoff valve, either butterfly or guillotiine style, at the intake manifold)
Now take that concept and run with it. If you take a natural gas line and plumb it into the intake of your engine then you can get that NG to displace some of the diesel fuel used, right?
Say anywhere between 25% and 75% power you can flood your intake tube with NG vapor then you can basically run your diesel engine on that "atmospheric" fuel instead of your injected diesel. Your power output can be the same while your diesel fuel pump actuation is less.
(I probably lost a few people at this point)
To a point you can displace a good amount of diesel fuel consumption with the NG "flooding." Then if you have strong transient loads your diesel fuel pump will instantly react to cover them while your "fogged' NG supply reacts. This works great constant speed / variable load applications like drilling or frac.
Anyway, there is a sweet spot between 25% and 75% (or so) load where the NG substitution rate is ideal. There are some older systems that run a very simple on/off gas valve that can send a ton of NG into the intake stream or none into the intake stream. Some of the newer systems use stepper motors on those valves to modulate NG flow relative to load and diesel usage to somewhat optimize the system but they are still "stand alone" third party bolt ons.
We are now working on a factory supplied solution that also takes into account basic engine operation to even further optimize this substitution rate. Lots of behind the scenes work on multiple diesel injection events combining w/ the NG flooding and other things, but trust me when I say that this technology is growing every day.
This is not to say that you can bolt on any "dual fuel fogger" system onto any diesel though. For instance, in the case of a Cummins QSK50 engine there are up to seven injection events per combustion stroke. One of those is very early and with a NG fuel charge you will run into massive pre-ignition problems. Injection timing is a crucial part of this picture that prevents it from being implemented across the board carefree-like. (Older technology engines like Cummins' KTA50 or Cat 3512/3516 with unit injection systems can handle it bolt-on slightly better b/c of the single injection event those engines have.)
I would bet that you see frac rigs with this dual fuel tech in the field next year (we already have field test units in operation and we showed one off at PBIOS last week) and dual fuel drilling rigs within a couple years.
There are drilling contractors and rig builders out there that have said they expect 75% of the market to be dual-fuel in the next few years. It's not a fly-by-night technology. Natural gas is here to stay in the US and you'll start seeing it more and more in your everyday lives.
Then there are spark-ignited NG engines (based on a proven diesel platforms) that are becoming very popular in fleet trucks (that have a central hub, used for day-trip type deliveries and service), refuse trucks, etc. Well servicing companies are starting to explore this technology for workover rigs and other applications (ie. water haulers) now.
(disclaimer: old friend in town, been out drinking all day, not totally coherent)Last edited by Strychnine; 10-26-2012, 09:44 PM.
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Originally posted by bigmuskie View PostWhat's the noise level with these NG fueled diesel engines they use on these drilling sites. PAM trucking have daycab trucks using NG and from about 15 to 20ft. away you can barely hear them ideling.
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Originally posted by Strychnine View PostPure NG engines are spark ignited. Due to cylinder pressures, fuel utilization, etc, you need around double the displacement to make diesel comparable power with gas.
Three 50 liter diesel SCR sets on a drill rig is about comparable to six 50 liter spark ignited natural gas SCR sets on a site.
Very doubtful theses are 100% NG engines, for that spark ignition reason.
With a dual fuel solution you can still run diesel ignition and diesel cylinder pressures which means you can have diesel style torque curves with your equipment.
*** engine tech warning***
A diesel engine runs purely on compression. No spark. Whatever fuel is in the cylinder... doesn't matter. At some point there's enough compression to heat the fuel enough that it combusts.
There are hybrid systems that use a specialized injector that run both NG and diesel at once. These systems, pioneered by Westport Innovations Inc in Vancouver, use two fuels through one injector. There is a 5% diesel injection into the cylinder to preheat the air (to take the place of a spark plug) then there is a 95% NG injection that autoignites (with the same cylinder pressure as a diesel application) that does work on the piston. This allows a "natural gas" engine to achieve diesel like torque curves while running on primarily NG fuel, but that's not what we're talking about here.
Now back to diesel engines...
If you take a diesel engine in the field and expose it to a cloud of fuelgas then the engine will ingest the gas. If the engine "throttle" position is maintained then this extra fuel gas will cause the engine to speed up. The engine fuel pump can cut supply but if the atmospheric gas is of sufficient quantity then it can keep the engine running or even cause a runaway.
Remember that a diesel engine does not have an intake air throttle blade. It controls speed purely on fuel input. If there's an uncontrolled fuel input (ambient cloud) then there is potential for uncontrolled speed. (The only way to stop a runaway due to atmospheric gas is with an air shutoff valve, either butterfly or guillotiine style, at the intake manifold)
Now take that concept and run with it. If you take a natural gas line and plumb it into the intake of your engine then you can get that NG to displace some of the diesel fuel used, right?
Say anywhere between 25% and 75% power you can flood your intake tube with NG vapor then you can basically run your diesel engine on that "atmospheric" fuel instead of your injected diesel. Your power output can be the same while your diesel fuel pump actuation is less.
(I probably lost a few people at this point)
To a point you can displace a good amount of diesel fuel consumption with the NG "flooding." Then if you have strong transient loads your diesel fuel pump will instantly react to cover them while your "fogged' NG supply reacts. This works great constant speed / variable load applications like drilling or frac.
Anyway, there is a sweet spot between 25% and 75% (or so) load where the NG substitution rate is ideal. There are some older systems that run a very simple on/off gas valve that can send a ton of NG into the intake stream or none into the intake stream. Some of the newer systems use stepper motors on those valves to modulate NG flow relative to load and diesel usage to somewhat optimize the system but they are still "stand alone" third party bolt ons.
We are now working on a factory supplied solution that also takes into account basic engine operation to even further optimize this substitution rate. Lots of behind the scenes work on multiple diesel injection events combining w/ the NG flooding and other things, but trust me when I say that this technology is growing every day.
This is not to say that you can bolt on any "dual fuel fogger" system onto any diesel though. For instance, in the case of a Cummins QSK50 engine there are up to seven injection events per combustion stroke. One of those is very early and with a NG fuel charge you will run into massive pre-ignition problems. Injection timing is a crucial part of this picture that prevents it from being implemented across the board carefree-like. (Older technology engines like Cummins' KTA50 or Cat 3512/3516 with unit injection systems can handle it bolt-on slightly better b/c of the single injection event those engines have.)
I would bet that you see frac rigs with this dual fuel tech in the field next year (we already have field test units in operation and we showed one off at PBIOS last week) and dual fuel drilling rigs within a couple years.
There are drilling contractors and rig builders out there that have said they expect 75% of the market to be dual-fuel in the next few years. It's not a fly-by-night technology. Natural gas is here to stay in the US and you'll start seeing it more and more in your everyday lives.
Then there are spark-ignited NG engines (based on a proven diesel platforms) that are becoming very popular in fleet trucks (that have a central hub, used for day-trip type deliveries and service), refuse trucks, etc. Well servicing companies are starting to explore this technology for workover rigs and other applications (ie. water haulers) now.
(disclaimer: old friend in town, been out drinking all day, not totally coherent)
I just did one of these conversions on R2A 3512 at schlumburger. Works very well
Side note. Don't ever hand an eletrical engineer a wrench!
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Originally posted by racrguy View PostI understood everything you said. Is there a cost savings associated with running NG? With engines that large I imagine hey'd take a LOT of NG.
A typical rig (three ~1400kW gensets) running an ideal 70% substitution rate can see upwards of $400,000 savings per year.
Encana claims to have saved $11MM in fuel in 2011 (compared to 2010) thanks to this tech.Last edited by Strychnine; 10-27-2012, 11:43 AM.
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