MDPE is Medium Density Polyethylene. Used for underground gas lines. IE firepit or to an outdoor BBQ. Is most common. MDPE gas pipe CANNOT be used inside of any building. Outside use ONLY!
I believe NOT I'm not qualified, but someone who is tells me that it cannot be used inside a building because of the risk that it would melt in the event of a fire and allow gas to escape - thus feeding the fire ! HTH
26mm
Orange pipe is for natural gas.
Coated Copper Pipe that is approved for underground only.
Yellow
it is yellow with blue band
Wrap the pipe threads with a thin layer of yellow tape and then screw the pipes together. pretty simple. If you can't do this then you shouldn't be messing with gas!
approximately 50mm internal diameter but you'll need to verify this with manufactures if you need it to be precise. For modelling purposes this will give you a rough idea.
The brown stripe on yellow mains gas pipes is a standardized color code that indicates the type of gas being transported. Yellow typically signifies that the pipe carries natural gas, while the brown stripe helps to distinguish it from other utility lines and indicates specific regulations or safety requirements. This color coding is important for safety and identification purposes, helping workers and emergency responders recognize the type of gas in the pipeline.
No.1 get a gas fitter to do so no such thing as diy gas work. No.2 if really stuck use gas type thread tape (yellow)
pipe
Gas lines in homes are most often done in flexible copper tubing. A fairly new product also being used that is easy to spot is the yellow flex pipe a "flexible, yellow polyethylene coated copper tubing that is continuously line-marked for clearer identification of liquefied petroleum and natural gas." It would come in various sizes- 3/8" to 3/4" or even more for industrial applications. Black iron or galvanized pipe is also commonly used.