1、先用眼睛目测一下阀门的表面是否光泽均匀，还要注意是否有裂痕、脱皮和明显的斑点等等，质量过关的阀门表面应该没有砂眼，且涂层的表面是细密光滑均匀的，如果出现了上述所说的一些缺陷，是会直接影响它的使用寿命。

1. First, visually inspect the surface of the valve to see if it has a uniform luster, and also pay attention to whether there are cracks, peeling, and obvious spots. The surface of the valve with good quality should not have sand holes, and the coating surface should be fine, smooth, and uniform. If any of the above-mentioned defects occur, it will directly affect its service life.

2、见过阀门的都知道，它的管螺纹与管道是直接相连接的，在选购时还要观察管螺纹是否有明显缺陷，还有管螺纹的有效长度，这将影响密封的可靠长度，这些都是需要用我们的双眼仔细观察的。

2. Anyone who has seen a valve knows that its pipe thread is directly connected to the pipeline. When purchasing, it is also necessary to observe whether there are obvious defects in the pipe thread and the effective length of the pipe thread, which will affect the reliable length of the seal. These are all things that require careful observation with our eyes.

3、阀门的材质有很多，不要贪图小便宜，有些售价比较低的，会容易因腐蚀而断裂，使用时间长了烂在管道中，在维修中会造成很大的困难。再者，选择合适的阀门关重要，阀门品种规格很多，选择不合适的会造成很大的影响。

3. There are many materials for valves, so don't be tempted by cheap prices. Some valves with lower prices may easily break due to corrosion, and if used for a long time, they will rot in the pipeline, causing great difficulties in maintenance. Furthermore, selecting the right valve is crucial as there are many types and specifications of valves, and choosing the wrong one can have a significant impact.