（1）先看表面光洁度，以及白度。
(1) Look at the surface finish and whiteness first.
（2）拿样品摔，容易摔碎者一般是高钙产品，当然要符合你们的要求价格合适的话是可以的。
(2) Sample breakers are usually high-calcium products. Of course, if the price is appropriate to meet your requirements, it is possible.
（3）拿样品用脚踩管材的边，看看是否能裂开，或者裂开后的断裂伸长率。
(3) Take the sample and step on the edge of the pipe with your foot to see if it can crack, or the elongation at break after cracking.
（4）耐侯方面挺麻烦的。最直接的办法就是拿到高温高光的地方放个几天，看表面变化率，但太浪费时间。主要看前3项就好。
(4) Weather resistance is troublesome. The most direct way is to get high temperature and high light place for a few days to see the surface change rate, but it is too time-consuming. Look at the first three items