... PEX-AL-PEX PIPE FOR HOT WATER, VERLAP-WELDING AND 1) BUTT-WELDING 2) Standard: ASTM F1281 3) SIZE: 1216,1418,1620,2025,.. Pex-al-pex ... 2")5163(2")6075(21/2") 2.Welding way:Overlap/Butt 3.Related standard:GB/T 18997, ... of radiator and wall;c)Heat and cold pipes for life,solar energy water heater,irrigation ... engineer in agriculture;d)Pipes for coal gas and natural gas,air- ...