One, the brass function 1, durability: History testifies whose life-span
 before beginning being used for A.D. in 2750, nearly boundless. 2,
hygiene function: The trace copper ion is beneficial to good health ,
has and the function , demonstration restraining the water bacterium:
That 99%'s bacterium middle relieves self in to entering brass system
within 5 hours is able to disappear. Copper is to unique but kill
material of bacterium of army group. 3, permeability: Any matter can not
 pass through the copper tubing equally including light, therefore being
 able to not propagate an alga. 4, is able to bear the temperature
function: The high temperature and the low temperature , block of wood
meeting change with the temperature but the occurrence character changes
 ability. Also can not produce the gas bad for the human body in being
put in fire. 5, connection method and intensity: Capillary welding ,
pressure meet , socket, the limit undertakes the pressing on of 3175
kilograms.Two, red copper is in charge of and the aluminium moulds tube economy ,
 the parallel technology contrast item: Synthesize cost of construction
 , have linked way , the curved function , stream ability , life time.
Red copper is in charge of: Synthetical cost of construction is lower;
The way linking up has welding , the socket , the card meet; 3 times
curved function outside diameters; The stream ability is too best;
Life-span of life time very equal with the building. The aluminium
moulds a tube: Synthetical cost of construction is high; The card
linking way is received; 5 times curved function outside diameters; The
 stream ability is too bad; Life time verifies without practice.All above counts contrast respectively describe as follows: 1, synthesizes cost of
construction: The synthetical cost of construction that red copper is in charge of is
able to mould a tube over lower than the aluminium , variety benefiting from that whose
 fine fault stream ability Ji Qi  assorts links way; The aluminium moulds but a tube if
 wanting to reach the equal with red copper tube fault stream ability , the tubing and
accessory being able to select and use bigger caliber, bring about synthetical cost of
construction thereby rising. If no so-called, whose fault stream ability cannot reach
design demand but.2, links way: Red copper has been in charge of since having very long history in building water
supply system , has taken form thereby than variety assorting links way, the way linking up
concretely has: Welding , socket , card cover link up , can according to the way designing , coming
 select and use the different request being under construction different connection; The aluminium
moulds a tube having a card to link one kind set at present only , similar to that red copper
manages dacron khaki cover connection, but external form the dimension is bigger. Kind of way
linking up applies to engineering construction middle here, pretend among bed course if dark,
definitely need the thickness increasing a bed course , make soil establish capital thereby since
the it's tubing and accessory external form dimension is bigger,