Technical standard of copper aluminum connecting pipe:

(1)Welding point: no pores,cracks,slag,burrs and burn,not fusion,no obvious oxide film,no plug hole without significantly reduced(Φ6.3hole is larger than 3.0mm);

(2)Air tightness: using a high pressure for 4.0MPa pressure for 5 minutes, no leakage;

(3)Pressure: after the air tightness check is qualified, slowly press the pressure to 13MPa,keep for 1 minute, without any cracks ;

(4)Bending: The sample is bent into a curved core diameter of 2 times than the nominal diameter of the pipe, after bending 180 degrees, the pipe does not produce wrinkles and cracks;

(5)Tensile strength: The tensile strength is at 65-118mpa, the pull part is on the side of the aluminum pipe, and the weld is above 10mm;

(6)KTG: Shrink good, sealed accessories have been melted, completely wrapped in copper aluminum joints, the seal can not turn.