前言
前言Foreword
铝的导热性能在金属中排名第三，仅次于银和铜，它的W/ (m X k)值可达到193，是10#碳素钢(46.4)的4.16倍;它的重量很轻，比重2.71g/cm ，是10#碳素钢的(7.8g/cm )的约三分之一。
铝的耐腐蚀性能高于铁，尤其是添加了一定量的其他金属后，它的抗氧化、抗老化（盐雾试验）性能，可达到10#碳素钢的5倍以上。
铝的加工性能非常优越，它可以通过热挤压工艺制成单根超长的无缝铝管，避免了用钢管作为换热芯体进行焊接而产生的缺陷，可以避免钢的高报废率，因而以铝代钢，它具有以下优点：
1．因为它导热系数比10#碳素钢高了4倍，所以在同等条件下铝合金的换热效果比10#碳素钢更佳，其性价比更高;
2．在防水垢问题上铝合金管要好于钢管、钢管换热器的盘管是碳钢经过热浸锌处理过的，其表面很粗糙容易结水垢，日积月累后水垢会越来越厚，会严重影响盘管的换热效果，即使我们也标配有电子水处理器,但其效果也不是很明显，而铝合金管表面很光滑不容易结垢，且铝的热膨胀系数远大于钢管，即使铝合金管表面产生水垢也会在水淋状态下自行剥离脱落，会大大增加盘管机芯的使用寿命,确保换热效果不受影响；
3．10#碳素钢经过仅200小时的耐腐蚀试验就锈迹严重，使用寿命大概在2—4年，但防锈铝合金却可以通过6000小时的耐腐蚀试验，其使用寿命可达到5年以上；
4．目前在行业里蒸发式冷凝器的排管焊接有两种方法：(1)用弯头与直管焊接，整个机芯盘管就有无数个焊接接头，(2)用钢带卷成圆管进行焊接，整个机芯盘管从头到尾都有一条焊缝，焊缝处最容易腐蚀，所以钢管机芯焊接位置最容易泄露，因焊接位置贯穿整个机芯，如机芯中间泄露则无法进行修补，我公司自行生产的铝合金管单管可达150m长，其长度足够一次弯曲成型使用，因此单管中间无焊缝，焊接位置只在集流管上，都在机芯外侧，因此即使焊缝处泄漏，也可随时补修；
5．由于蒸发冷安装经常放置到屋顶位置，有些大功率的蒸发冷设备自身重达10多吨，放在屋顶的话，建筑往往达不到承重要求而需要进行加固，耗资甚巨，但防锈铝合金管做的蒸发冷重量只是钢管的60%左右，重量大大减轻，放置在屋顶的话大多数建筑无需加固，即使要加固的话工程量也很小可以省去很多时间和资金。
Foreword
The thermal conductivity of aluminum is ranked third in the metal,after the silver and copper, its W/(m X K)value can reach 193,is 10# carbon steel(46.4)4.16 times; it is light in weight, the proportion of 2.71g/cm ,10# carbon steel(7.8g/cm )of about 1/3.
Aluminum corrosion resistance than iron,especially added a certain amount of other metals, its antioxidant,anti-aging(salt fog test)performance,can reach more than 5 times the 10# carbon steel.
Processing properties of aluminum is very superior,seamless tubeswhich can be single long made by hot extrusion process,avoids the defects caused by welding steel pipe as heat exchange core body,canavoid high scrap steel,thus with aluminum and steel,it has the following advantages:
1. because of its thermal conductivity than 10# carbon steel high 4 times,so the heat exchange efficiency of aluminum alloy under the same conditions than 10# carbon steel is better,the price is higher;
2．in the water fouling problem of aluminium alloy pipe is better than steel pipe, coil heat exchanger tube is carbon steel after hot dip zinc treated, the surface is very rough easy scaling, after days and months multiplyingscale will be more and more thick, will seriously affect the effect of heat exchange coil，even though we also comes standard with electronic waterprocessor,but its effect it is not obvious．and the aIuminum alloy tubesurface is very smooth and not easy to scale．and the aIuminum thermal expansion coefficient is much larger than the steeI pipe．alumjnum alloytube surface even produce scale willbe in the water state to peel off，wilI greatly increase the service life of the coll core，Ensure that the heating effect is not affected
3．1 0#carbon steel corrosion test after only 200 hours of rust seriously,service life is about 2-4years，but the antirust aluminum alloy can be acorrosion test for 6000 hours,its service life can reach more than 5 years；
4．is currently in the industry of evaporative condenser pipe welding in two ways：(1)with the elbow and straight pipe welding，the entire core coilhas a welded joint，(2)are welded steel pipe to form a round，the whole movemenf from A to Z coil has a weld,weld the most prone to corrosion,so steel core welding position most easily leak，because the welding position throughout the movement，such as the core intermediate leakscannot repair,aluminum alloy our company’s own production tubes up to 150m long，and the length of a bending forming enough use, because there is no weld this pipe，welding position only in the manifold，inmovement outside，so even if the weld leakage，but also can repair；
5．due to evaporative cooling instailation often placed in the position of the roof．the evaporative cooling equipment and some high power selfweighing more than 1 0 tons,on the roof,the building cannot reach thebearing requirements and needs strengthening．expensive,but theantirust aluminum alloy tube evaporative cooling steel tube weight is onlyabout 60％，weight greatly reduced，placed in the roof of the words most building without reinforcement．construction quantity if reinforcement is also very small can save a lot of time and money．
