杭州方管是一种中空的长条钢材，因为截面是正方形所以叫做方管。大量用作输送流体的管道，如石油、天燃气、水、煤气、蒸气等，另外，在搞弯、抗扭强度相同时，重量较轻，所以也广泛用于制造机械零件和工程结构。
不锈钢方管性能
金属在大气中都可与氧气反应在表面形成氧化膜，普通碳钢上形成的氧化铁会继续进行氧化，使锈蚀不断扩大，比较终形成孔洞。
这可以利用油漆或耐氧化的金属进行 电镀来保护碳钢表面，但这种保护层只是一种薄膜，如果保护层被破坏，下面的钢便又开始锈蚀。
不锈钢管是否被锈蚀与钢中的铬含量有关，钢中的铬含量达到12%时便不容易被腐蚀。 而喜有沃201不锈钢管中铬含量达到13%以上，304不锈钢管中铬含量达到18%以上。
适用条件
在大气中，不锈钢管表面生成了一层钝化的、致密的富铬氧化物而保护表面，可防止进一步再氧化。
这种氧化层极薄，透过它可以看到钢表面的自然光泽，使不锈钢具有特的表面。
如果铬膜一旦破坏，钢中的铬与大气中的氧重新生成钝化膜，继续起保护作用。
在一些特殊环境下，不锈钢也会出现某些局部腐蚀而失效，但不锈钢与碳钢不同，不会出现均匀腐蚀而失效，因此腐蚀余量对不锈钢管来说没有意义。
不锈钢方管优点
不锈方管被广泛的使用，当然也是有一定的原因的，其中比较主要的就是其使用寿命很长，具有很好的抗腐蚀性，并且本身自重较轻，但强度很大，为产品减少了负重，增加了其承受能力，让消费者用得更加的放心。
Hangzhou square tube is a kind of hollow long steel, because the section is square, it is called square tube. A large number of pipelines are used to transport fluid, such as oil, natural gas, water, gas, steam, etc. in addition, when bending and torsional strength are the same, the weight is lighter, so it is also widely used to manufacture mechanical parts and engineering structures.
Properties of stainless steel square tube
Metal can react with oxygen in the atmosphere to form oxide film on the surface, and the iron oxide formed on the common carbon steel will continue to oxidize, so that the corrosion will continue to expand, and finally form holes.
This can be done by using paint or oxidation-resistant metal plating to protect the carbon steel surface, but this kind of protective layer is only a thin film, if the protective layer is damaged, the steel below will start to rust again.
The corrosion of stainless steel pipe is related to the chromium content of steel. When the chromium content of steel reaches 12%, it is not easy to be corroded. The chromium content of xiyouwo 201 stainless steel pipe is more than 13%, and that of 304 stainless steel pipe is more than 18%.
Applicable conditions
In the atmosphere, a layer of passivated and dense chromium rich oxide is formed on the surface of stainless steel pipe to protect the surface and prevent further reoxidation.
This kind of oxide layer is very thin, through which we can see the natural luster of the steel surface, so that stainless steel has a unique surface.
If the chromium film is destroyed, the chromium in steel and oxygen in the atmosphere will form a passive film again, which will continue to play a protective role.
In some special environments, stainless steel will also have some local corrosion and failure, but unlike carbon steel, stainless steel will not have uniform corrosion and failure, so the corrosion allowance is meaningless for stainless steel pipes.
Advantages of stainless steel square tube
The stainless square tube is widely used, of course, for some reasons. The main reason is that it has a long service life, good corrosion resistance, light self weight, but great strength. It reduces the load of the product, increases its bearing capacity, and makes consumers feel more comfortable using it.
