CNG Vehicles

is it diesel ? if it is diesel presure is about 170 atmospheres approx 15000 psi

• Common rail - Wikipedia, the free encyclopedia On diesel engines, it features a high-pressure (over 1000 bar/15000 psi) fuel .... Since the fuel pressure energy is stored remotely and the injectors are ...
  History - Common rail today - Principles - See alsoen.wikipedia.org/wiki/Common_rail - Cached - Similar

Compressed Natural Gas.

According to the Wiki link above, GB has no CNG filling stations (none listed anyway). Is this type of motorfuel available across the pond?

• In the UK we call it LPG. Liquefied Petroleum Gas
• Is it the same ?
• LPGMAP :: locating LPG filling stations Find all LPG filling stations centered on a postcode or town and shown on an interactive map. Download into your GPS or sat nav the entire UK filling ...
  www.lpgmap.co.uk/ - Cached - Similar
• LPGMAP :: LPG filling station location Where to find LPG and bio diesel filling stations in the UK displayed on an interactible and searchable map.
  www.lpgmap.co.uk/map.php - Cached - Similar Show more results from www.lpgmap.co.uk
• Get LPG - Find LPG and AutoGas refuelling stations in the UK GetLPG maps the location of LPG and Autogas fuel stations in the UK. All the information is free and can be downloaded to your GPS or mobile phone.
  www.getlpg.org.uk/ - Cached - Similar
• LPG from Autogas Ltd Recently we've opened over 20 new LPG stations across the UK - Find your nearest. ... Download POI files to your Sat Nav to find your nearest LPG station ...
  www.autogas.ltd.uk/ - Cached - Similar
• LPG refuelling stations Find your nearest LPG refuelling station using these online tools.
  www.autogas.ltd.uk/whereToBuyMap.htm - Cached - Similar Show more results from www.autogas.ltd.uk
• Find LPG Filling Stations in the UK Find LPG Filling Stations in the UK. Business Name, County, City, Post Code ... LPG Filling Stations in Northern Ireland. LPG Filling Stations in Scotland ...
  www.findlpg.com/ - Cached

Sorry to disagree with you on this one. CNG is definitely compressed Natural Gas and there are a very few filling stations in the UK. They fall into 2 size groups. Ones with virtually no storage and these are domestic overnight fill machines. Just a compressor and control gear. The larger ones are used for fleet filling and have a bank of high pressure bottles at 350bar yes 350bar and a dispenser similar to the ones seen on LPG pumps on the garage forecourt. If you fill a CNG system with LPG the results would be disappointing, however if you filled an LPG system with CNG the results would be catastrophic.

In reply to the original post:

90psi sounds way to low for a common rail direct injection engine. I would have an expert look at the control gear.

Regards,

Hello Gasman

Do you (or anybody else) know how these things work? For LPG (stored as liquid in the car's tank, at something like 4 barg (60 psi)) it could in principle be injected as liquid, as with diesel or modern petrol. But in practice I believe the LPG is evaporated and mixed with air in a gas carburettor. Is this correct?

On CNG, pressure anything up to 350 bar needs to come down a lot before feeding to the engine. I'd have thought 90 psi was ample to get the gas in, but I don't know the details of the gas train.

Cheers.......Codey

on lpg its is stored as a liquid it goes through a presure regulator first then to a vapouriser normaly heated by the engines coolant to raise it to a vapour it then goes via a demand valve to the inlet normaly a ring shaped like a venturi to create suction as the inlet air goes past it, thus creating sucktion for the demand valve to operate if its fitted as an after market kit.

if built that way the carb is somtimes a special one.

fork lift trucks have a lot of lpg fitted as its cleaner than gasoline ( petrol) or diesel.

any good ?

Thanks Peter

That confirms my assumption about LPG. The arrangement you describe amounts to what I meant by a gas carburettor.

Any idea about CNG? I can't see why it wouldn't be similar to LPG, but with a lot more pressure reduction.

Cheers........Codey

I agree but i have no experiance of cng it should work the end result is the same gas

the only diff as you say is the presure before the regulator and one being a liquid.

if gas went into a voapouriser nothing would happen as its already a gas. so assuming the first presure regulator and pipiing up to the regulator can stand the presure it should work.

its the presure thats the problem with the first regulator

another way round it would be to have two tanks and couple the output from the cng after the pressure has been reduced couple it to the pipe work after the presure reg on the lpg then it should all work nicely and safely

Hello Codemaster,

The 350bar I referred to was the filling station pressure which has to be higher than the vehicle tank pressure. The tractor units I was involved with we powered by MAN diesels and the manufacturers system stored the gas on the vehicle at 210bar max and required refilling at 20bar as I remember it. The cylinder head had 2 injectors, one for the gas and on for the diesel which provided the ignition timing and combustion initiation. It was done this way to minimise the power loss that would occur if an atmospheric carburettor was used to get the gas into the cylinders. The gas reduces the amount of air drawn in during the induction stroke and the fuel supply has to be trimmed back to retain the correct air/gas ratio.

As the gas is injected during the compression stroke it has to be above the pressure in the cylinders at that part of the cycle as it leaves the injectors, so it must be a lot higher than that before the injectors and other control gear to get the amount of gas into the cylinder in the time available, hence the 20bar minimum tank pressure. As LPG does not normally get up to the pressure required for direct injection it is usually evaporated and induced into the intake manifold in the throat of a fairly simple carburettor.

The tax scheme in the UK does not allow for a reasonable ROI on a conversion if the operator has to provide his own filling station. The client I did the filling station for spent almost £250,000 eight years ago on the filling station alone and because the tax regime changes 12 months after it was installed he has not progressed past the original 4 units. I recall the drivers comments all being favourable, plenty of power when required and less vibration and noise than the straight diesel versions of the same engine.

Regards,

Gasman

Thanks Gasman that's interesting.

I realised the vehicle tank pressure would be less than the filling station pressure, but didn't know by how much, that's why I said up to 350 bar.

Do you mean the gas relies only the tank pressure (min 20 bar) for injection? If so it would need to be early in the compression stroke, as at the end of the stroke the cylinder pressure is well above 20 bar even before the diesel is injected. Compression ratio is around 20:1, and of course that's really a volume ratio, pressure rise is much higher.

Thanks also peterglyq for the raft of links. When I have an hour or 2 to spare I'll have a look!

Cheers.....Codey

In the LPG thread running parallel to this one I ramble on about my propane powered truck.

I have thought many times about a backyard LNG charging station, or perhaps more correctly compressed natural gas because I do not think it is compressed to the point of becoming a liquid.

I know, or think I know, that 3000 psi bottles are required - just like as are used for the storage of oxygen for oxy-acetylene torches.

But, my point is that I would suspect the only difference, after sufficient stages of pressure reduction, between LPG carburization and CNG carburization would be jet (or fuel orfice) size.

What would do you think?

Hello Coldspot

I'm pretty sure you're right about the jet (or fuel orifice) size.

Natural gas (methane) at room temperature cannot be liquified by pressure alone, as the critical temperature is -82°C. When it's stored as a liquid (LNG) it has to be kept cold. So for CNG, as you say you'd need something like 3000 psi.

LPG (propane) has critical temperature 96.8°C so can be stored as liquid. Rechecked the figures and 4 bar I said in #7 is too low. Pressure at 30°C is about 10 barg. In UK, propane tanks for domestic heating have design pressure 250 psig (17.2 barg) which corresponds to just over 50°C. Of course they have a pressure relief valve.

Cheers.......Codey

Dear Sir / Madam

How we can purchase some quantity of gas dispenser,the domestic overnight filling one.

Regards

M. Sadat

For Alsadra General Trading Co.

genral info for lpg

Search Results

1. Auto LPG - Power with economy - FAQ I have heard that LPG systems causes problems like backfiring does your system suffer ... We can convert the majority of petrol cars. Aldesa LPG systems has been used to ... Clean workshop means clean work. No car back with oily stains. ...
   www.autolpg.co.uk/faq.html
2. lpg car conversions way lpg works lpg gas conversions save you money, lpg car conversions are the future. How do LPG systems stop the petrol system from working? ...
   www.amershamauto.com/pages/how_lpg_works.htm
3. LPG Conversion - How does it work? How Does LPG Work? An LPG Conversion works in exactly the same way as a normal ... Earlier LPG systems are renowned for having problems when fitted to modern ... Also, LPG-converted cars are now starting to rise in residual value as ...
   www.futurefueltechnology.co.uk/.../how_does_lpg_work.php
4. WPS:LPG There are a number of reasons why I wanted an LPG car: low tailpipe ... atoms and use it directly to do the work you originally intended. .... I've worked out a simple, safe and reliable ``gas-can'' system; see below for details. ...
   www.wps.com/LPG/LPG-book-final.html
5. FREQUENTLY ASKED QUESTIONS, LPG TECHNICALITIES & LEGISLATION | WWW ... Generally 3-5 working days depending on the conversion. ... What technical service do LPG-Cars offer to their customers? ... Yes, it is crucial that your LPG system is serviced annually or every 12000 miles. We can service a variety of ...
   www.lpg-cars.co.uk/faq/
6. Autogas - Wikipedia, the free encyclopedia Petrol engined cars which have not been fitted with LPG/autogas systems by the manufacturers ... Liquid phase injection systems do not use a converter, .... These work by sensing that the engine is running by detecting ignition pulses. ...
   en.wikipedia.org/wiki/Autogas
7. Open Loop LPG Systems How do LPG systems stop the petrol system from working? ... relay has the ability to isolate the petrol injector(s) from the car's engine management system. ...
8. www.chilterngascars.co.uk/cars/lpghowb.htm
9. Go LPG - Which type of LPG conversion do you need? If installed on a fuel injected car the system will need an 'emulator' ... Inputs from a number of sources must be provided or it cannot work, those being - ...
   www.go-lpg.co.uk/which_conversion.html
10. How does an LPG fuel system work in a car? – The Blogs at ... 12 May 2009 ... Home > Keep Asking > How does an LPG fuel system work in a car? ... Many cars that burn LPG are bi-fuel cars that can burn both gasoline and ...
    blogs.howstuffworks.com ›
11. LPG Autogas FAQ Does it matter what LPG system is installed in my car? ... to do the work to ensure a safe and satisfactory conversion and get the strength of the ... You can't do this because the car's LPG filling point only accepts LPG hose nozzles. ...
    www.drivelpg.co.uk/faq.php

and CNG info

1. HowStuffWorks "How Natural-gas Vehicles Work" "How Natural-gas Vehicles Work." 09 September 2005. HowStuffWorks.com. <http://auto.howstuffworks.com/fuel-efficiency/alternative-fuels/ngv.htm> 10 August ...
   auto.howstuffworks.com ›
2. Compressed natural gas - Wikipedia, the free encyclopedia Jump to CNG cars‎: CNG cars available in Europe are bi-fuel vehicles burning one ... Authorized shops can do the retrofitting, this involves installing a CNG cylinder in the ... installing a CNG injection system and the electronics. ...
   en.wikipedia.org/wiki/Compressed_natural_gas
3. Hybrid Vehicles - Alternative Fuels - Alternative Fuel and Hybrid ... 11 Aug 2010 ... Frankie Say: Why Did 1980s Cars Get Better Mileage? ... work out on a Soloflex; and regularly listen to The Cure, U-2, Depeche Mode and The ... So how does that stack up against Ford's current mileage master the 2011 Fiesta with the ... Hybrid Tax CreditsCNG Conversion CompaniesWhat is a PZEV? ...
   alternativefuels.about.com/
4. Alternative Fuel CNG Engine Conversion LPG Hydrogen Erdgas Buy the kit from Omnitek and our engineers will tech you how to do the conversion! ... CNG Conversion Kit for Cars - Injection System Bi-Fuel Kit ...
   www.omnitekcorp.com/altfuel.htm
5. EXHAUST EMISSIONS FROM NATURAL GAS VEHICLES File Format: PDF/Adobe Acrobat
   by NO Nylund - 2000
   vehicles which do not have sophisticated exhaust gas aftertreatment systems. ..... mean that in the future the alternative fuel systems have to work .... Compared to this, the amount of work on natural gas fuelled vehicles is so far ...
   www.apvgn.pt/documentacao/iangv_rep_part1.pdf
6. How Does Natural Gas Power a Vehicle? | eHow.com How Does a CNG-Powered Vehicle Work? How Natural Gas Vehicles Work ... called Integrated Storage Systems house the compressed natural gas in a fiberglass ...
   www.ehow.com
7. Clean Vehicle Education Foundation Why use natural gas as a fuel? How do natural gas vehicles work? ... Vehicle fuel system conversions are addressed in certain NHTSA provisions, ...
   www.cleanvehicle.org/technology/
8. How does CNG Conversion Work How to Maintain Natural Gas Vehicles · Why Convert to Compressed Natural Gas · How to do Natural ... But do you know how CNG conversion is accomplished and how it works? ... For an inside look at how a CNG/gasoline bi-fuel system works, ...
   cngunited.com/support/how-does-cng-conversion-work
9. Can You Convert to Natural Gas? | GreenCar.com 21 Jul 2008 ... One of the challenges for CNG engine system manufacturers in the U.S. is the time and expense to achieve certification for its conversion ...
   www.greencar.com/articles/can-convert-natural-gas.php
10. Can I run a car on natural gas? — Autoblog Green 23 Apr 2009 ... What does the future hold for natural gas vehicles? .... There are more and more EPA certified systems all the time. ... at home or at work for the foreseeable future, CNG refueling stations are popping up all over the ...
    green.autoblog.com/.../greenlings-can-i-run-a-car-on-natural-gas/

Searches related to how does cng systems work on cars

does natural gas vehicle work

do natural gas cars work

can cars run natural gas

Thanks for the great links. Here are my natural gas links, in case you are interested:https://docs.google.com/document/d/1NbaKYme3bqOw0b6KMxXSjOLHLNeflalPy9gIAiTYFMQ/edit

LPG conversions for Diesels ? Its not a true conversion as gas has a higher flash point than diesel and wont ignite in the engine like diesel but it does burn once the diesel has been injected, adding to the combustion process and if the figures are to be belived improving the output.

has anyone out there tried one of these conversions ?

About 1,020,000 results (0.29 seconds)

CR4 Admin: Modified Post

Copyright Violation: Reduced copied text according to copyright law. Please see Section 13 of the CR4 FAQ about posting copyrighted material.

I would guess here a few things:-

1) its a car

2) its a gas engine eg. it uses spark plugs not glow plugs.

Am I correct upto now?

Perhaps you could fill in the rest of the needed infos....thanks in advance.

I had cng,it was loaded up to 200 bar, and you are talking about a so lower pressure;you should go to fill it again (is not for ever and using it since 98's is good enough)...I dont remember know the min.work pressure for the regulator.-

i believe ford dedicated cng is far different than my gmc dual fuel which i had installed. tank press was up to 3400 psi and "mixer valve" released fuel at 1 psi into air filter body .through a large 1 inch id rubber hose.

the low cng fuel cut off was originally set at 500 psi which it would then automatically kick in gasoline system. had adjusted to 125 psi before switching to gasoline.

in my "mixer valve" at the high pressure inlet there was a metal mesh filter which looked like the size of a pencil top eraser, made of metal beads as in a sugar cube texture. located at end of inlet pipe. 5$ part. was plugged and dirty. can do yourself if you shut off tanks, purge lines, remove inlet pipe, pry out filter and at least inspect.

your vehicle sounds like a diesel engine converted to cng. mine was a gasoline cng dual fuel which is probably very different. when a cng vehicle does not start, there is a very obvious smell of cng near the tail pipe which is a good indication that the system is getting cng through the motor. good luck.

GM and Dodge are going to be selling bifuel CNG/gasoline pickup trucks. Dodge will start with 2,000. GM will send them out for conversion. This can be done to about any gasoline vehicle. Cost should be about $4,000, but probably will be much higher from a manufacturer. 3M has also come out with a new, lighter and less expensive CNG tank design.

Cramer of MSNBC excited about natural gas vehicles.http://www.cnbc.com/id/47076070/Cramer_Visits_CNG_Refueling_Station