ordering new cng trucks.

Seems like others in your area are doing the same

2013-09-06 [HR][/HR]WACO, Texas -- Central Freight Lines has placed an order for 100 Freightliner M2 112 trucks powered by compressed natural gas (CNG).
The trucks will contain the Cummins Westport ISL G engine, wth 260-320 hp and up to 1,000 lb-ft. of torque. Central Freight Lines says it has partnered with a fuel supplier to build CNG stations in Fort Worth, Houston and San Antonio, Texas

 

Saddle Creek just bought a bunch more of them down here, and a beer distributor bought quite a few as well. You would have thought Tampa Truck Center was having a blowout sale on them.

 

Saddlecreek uses the Allison automatic.

 

I've never used LNG, but CNG trucks and buses are very popular in Ukraine, so i can share my experience.

first of all CNG engine got different fuel injection system (NG valves), CNG ruductor, ignition system spark plugs... throutle and egr, and cata;istic converter (if equipped).

the most potentially dangerouse thing of CNG truck is CNG tank (tanks). They are under pressure of up to 250 BAR. but they newer blow on road, they may explode during refilling only and it is dangerouse time when they fill them up. here every tank must be inspected anually and must be tested sometimes with water under high pressure to find any sign of crack, becouse when this tank blows - no fire, but truck destroyed and it may easily kill personel.

when NG leaks it goes up, becouse it is generally methan. stories like someone died in cab.. really I do not belive, becouse CNG trucks are with daycabs, no sleeper allowed and gas detectors are installed. all stories aboud dead drivers in sleepers are about small LPG hob inside cab.....! yep, they kill drivers!

bad news - CNG engine starts hard when it is below zero outdoors. so it would be good idea to install coolant heater, like webasto hydronic for example, of course diesel powered. other good idea - combined gas - natural gas engine. really gas is used to warm up engine and switch it to CNG.

 

BTW, all new trucks got plastic CNG tanks, old tanks are made of steel. Manufacter say that new tanks are lightweight and less dangerouse in case of explosion becouse fractions are not so heavy like steel pices and give a victim more chanses to survive.

Just some pics about how bad is CNG tank explosion













Usually it happens with old steel CNG tanks installed by DIYers. So I'd change tanks with new every five years. Other good idea to stay away from truck during refilling and... do not fill CNG tank to 100%, better for 80%.

Good news, in case of accident it is not so easy to damage CNG tank, its wall is thik and tought, so usually no fire if CNG vehicle crashes. And when CNG tank is broken NG vents to atmoshphere with rapid drop of temperature (about -25-30 dgr C ore less), so it is hard to ignite it. Gas ore Diesel on road are very dangerouse, you know why!

 

I am driving a Peterbilt cng daycab tractor with two saddle tanks and no tanks behind the cab. I drive within a 150 mile radius of Milwaukee. The tractor currently has 9000 miles and gets anywhere from 4.8 to 5.6 mpg depending on weight and city/highway miles. I can get about 350 miles before I have to refuel. It has the same engine, transmission, and gear ratio as the opening post with a 200 inch wheelbase.

 

really NG is sold here in cube meters, ore in cube feet, but in USA theu use diesel equialent. But I'd call this unit a bit incorrect, becouse CNG ore LNG engine is not DIESEL, it works like an engine in your fourwheeler with spark plugs and 1:10-12 compression ratio. So I'd compare NG with gas. 1000 L of methan is 0.67 kg, 1 kg of methan is 1490 L under normal atmospheric pressure. So you can easily convert all this stuff to galons and pounds.

Heat output of 1 m3 of methan equal to 1.7 l of gas,· 1.3l of diesel and about 2 l of LPG. But diesel cycle engine is more then 30% effecient thn gas engine. But this is not all. Octane ratio of methan is about 130, so higher compression may be used and higher boost pressure. so really it is like comoare gas and diesel engine.

 

It's just me, BUT, because of the low engine rating ( and the fact that we have had good luck with auto's) I would definitely look into the DT-12 automated tranny, you get two more gears and never have to worry about missing a shift, may get better fuel mileage also as it skip shifts EVERY time it can.

JMHO