The differences between compressed natural gas (CNG) and liquefied natural gas (LNG) are the methods of production and storage.
Both fuels are primarily methane (CH4). LNG is natural gas ‘frozen’ to less than -162o Celcius (-212o Fahrenheit) to liquefy it. The advantage of liquefaction over compression is that the fuel is at a higher density, meaning more energy is contained in the same space – LNG is roughly 600 times the density of natural gas at standard pressure.
In general, LNG is more commonly used for heavier vehicles whereas CNG is used for lighter vehicles. This is not a hard and fast rule though and both fuels may be used in either class of vehicle.
Once the gas is liquefied, it must be kept cold or it will revert to its gaseous state, thus LNG cylinders are designed in a similar fashion to a thermos flask, (i.e. with substantial insulation). This design allows for the fuel to be kept cold for two weeks or more.
Automatic Circumferential welding machine-LNG Cylinder
Circumferential seam welding machine can adopt special machine welding or robot welding form, and the workpiece can be automatically loaded by manual assistance or aerial manipulator. It can be configured with contact or non-contact welding seam automatic tracking system to automatically locate and track the welding seam position.
Welding robot workstation for inlet and outlet liquid pipes and pipe joints
The robot of the inlet and outlet liquid pipe and the double-sided joint is welded automatically. Welding process: TIG. Welding method: V-shaped double station layout; each station is equipped with 3 station fixtures, corresponding to 3 different inlet and outlet pipe workpieces, using manual picking and placing, positioning the workpiece, and robot automatic welding. Robot system: The robot system is equipped with products of Japan’s MOTOMAN company, including the body of the arc welding robot embedded in the MA1400 cable and the robot control box.